MUSCLESTRUCT abdominal cavity

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MUSCLESTRUCT abdominal cavity Powered By Docstoc
					MUSCLE/STRUCT.              ORIGIN                      INSERTION                   FUNCTION                             INNERVATION                 BLOOD SUPPLY
ANTERIOR NECK/              Anterior border of          Apex = jugular
CERVICAL TRIAN.             SCM, inferior border of     (suprasternal) notch
                            mandible, median line       Roof = subcutaneous
                            of neck  makes 3           tissue containing
                            triangles =                 platysma
                            submandibular,              Floor = pharynx, larynx,
                            muscular, carotid           and thyroid gland
Sternocleidomastoid m       Lateral surface of          Sternal head = ant          Ipsilat tilting of head; flex neck   Accessory n                 Superior thyroid a
– acts across all           mastoid process of          surface of manubrium        ipsilat while rotating sup’ly to
cervical vertebral joints   temporal bone and           Clavicular head = sup       opposite side; bilaterally flex
including the atlanto-      lateral half of superior    surface of med third of     neck to thrust chin forward
occipital & atlanto-        nuchal line                 clavicle                    (pulls head downwards)
Omohyoid m – 2              Superior: greater horn of   Both bellies connected      Assists strap mm in pulling the      Brs of Ansa cervicalis      Superior thyroid a
bellies = superior and      hyoid bone                  by intermediate tendon      hyoid apparatus inferiorly;          (C1-3)
inferior; lies lateral to   Inferior: sup border of                                 depresses, retracts, and steadies
sternohyoid                 scapular, just medial to                                hyoid bone
                            scapular notch
Digastric m = 2 bellies     Ant belly: digastric        Both bellies connected      Depression of mandible if hyoid      Anterior, trigeminal n.
                            fossa of mandible           by intermediate tendon,     fixed and/or elevation of hyoid      posterior, facial n.
                            Post belly: mastoid         which is attached to the    bone if strap mm relaxed,
                            notch of temporal bone      greater horn of the hyoid   depending on what mm it is
                                                                                    used with. Complex
                                                                                    involvement in swallowing and
                                                                                    chewing. Work together
Infrahyoid (strap) m –                                                              Anchor hyoid bone, sternum,          Ansa cervicalis n           Superior thyroid a
loc inf to hyoid bone;                                                              clavicle, and scapula; depress
made of 4 mm                                                                       hyoid bone and larynx during
superficial plane =                                                                 swallowing and speaking;
sternohyoid and                                                                     steady hyoid bone
omohyoid mm; deep
plane = sternothyroid
and thyrohyoid mm
Thyrohyoid m runs          Oblique line of thyroid     Inf border of body and      Depresses hyoid bone and             Ansa cervicalis n (C1 via   Superior thyroid a
sup from oblique line       gland                       greater horn of hyoid       elevates larynx                      hypoglossal n)
of thyroid cartilage to                                 bone
hyoid bone; deep to sup
part of sternohyoid m
Sternohyoid m  thin        Post surface of             Body of hyoid bone          Depresses hyoid bone after it        Ansa cervicalis n (C1-3     Superior thyroid a
narrow m that lies          Manubrium and medial                                    has been elevated during             brs)
superficially parallel      end of clavicle                                         swallowing
and adjac to ant median
Sternothyroid m --.         Post surface of             Oblique line of thyroid     Depresses hyoid bone and             Ansa cervicalis n (C2 &     Superior thyroid a
Lies deep to               manubrium                  cartilage                   larynx                             3 brs)
sternohyoid m, covers
lateral lobe of thyroid
gland, attaching to
oblique line of lamina
of thyroid cartilage
above it
Platysma m                 Inferior border of         Fascia covering superior    Draws corners of the mouth         Cervical branch of facial
                           mandible, skin, and        parts of pectoralis major   inferiorly and widens it (facial   N (CN VII)
                           cutaneous tissues of       and deltoid MM              expressions of sadness and
                           lower face                                             fright); draws skin of the neck
                                                                                  superiorly when teeth are
Carotid sheath – seen       From the base of the        On superficial surface
by reflecting SCM,          skull to the root of the    will find the ansa
surrounds int jugular v     neck; formed by fascia      cervicalis n
(laterally), carotid a      extensions of all three
(medially), and the         layers of deep cervical
vagus n (b/w the 2)         fascia fusing together
 Torticullis = caused by unilateral shortening or contraction of one SCM m.  congenital = birth trauma; adult = muscle spasm
 Submandibular triangle borders are mandible and both bellies of digastric m; filled almost by submandibular gland; submandibular lymph nodes, hypoglassal N,
     mylohyoid N, parts of facial A and V
 Carotid triangle borders are scm, sup belly of omohyoid and post belly of digastric m; contains carotid sheath and contents. Ext. carotid A and branches, hypoglossal N,
     superior root of ansa cervicalis, accessory N, thyroid, larynx, pharynx, deep cervical nodes, and branches of cervical plexus.
 Muscular triangle borders are scm, sup belly of omohyoid, and medial line of neck; contains sternothyroid and sternothyroid MM, thyroid and parathyroid glands.
 Posterior cervical triangle borders are trapezius, SCM, and middle 1/3 of clavicle  2 triangles = occipital (part of jugular vein, posterior branches of cervical plexus,
     accessory N, transverse cervical A, cervical lymph nodes) and supraclavicular (Subclavian A and sometimes V, suprascapular lymph nodes)

Thyroid gland –            Lower neck to thoracic                                 Secretes thyroid hormone (TH =     Superior, middle, and       Superior and inferior
endocrine gland in neck    inlet; isthmus located                                 regulates metabolic rate or        inferior cervical           thyroid aa
loc deep to                just below cricoid                                     BMR)  TH prod highly              sympathetic ganglia
sternothyroid and          cartilage of larynx;                                   requires iodine
sternohyoid mm; large      pyramidal lobe extends
right and left lobes on    sup’ly from isthmus left
either side of ant         of median plane (dev
trachea connected by an    from remnants of
isthmus and one            thyroglossal duct)
pyramidal lobe
Thyroid cartilage of       Sup’ly attached to hyoid   Inf’ly articulates with
larynx – largest of        bone via thyrohyoid        cricoid cartilage via
cartilages; one of nine    membrane                   cricothyroid joints
in laryngeal skeleton;
features = greater horn,
oblique line, lesser
horn, laryngeal
prominence, superior
thyroid notch
Cricoid cartilage of      Sup’ly articulates with     Inf’ly attaches to 1st
larynx- one of nine       thyroid cartilage via       tracheal ring via
cartilages in laryngeal   cricothyroid joints         cricotracheal ligament
Cricothyroid m            Ant-lat part of cricoid     Inf margin and inf horn    Stretches and tenses vocal fold     External laryngeal n
                          cartilage                   of thyroid cartilage
Tracheal rings –
incomplete (post’ly)
cartilaginous rings that
make up tracheal tube
Parathyroid glands –         Tightly adhered to                                   Vital for maintaining blood           Thyroid brs of cervical     Inferior thyroid a and
superior and inferior        thyroid glands                                       Ca2+ levels  secretes                sympathetic ganglia         some times Superior
lobes that lie along                                                              parathyroid hormone (PTH) that                                    thyroid a
medial half of post                                                               inc’s blood Ca2+ levels when
surface of thyroid                                                                too low
gland; when removing
the gland, need to leave
at least one lobe behind
to prod PTH
 Thyroid cartilage of larynx is more prominent in males so they have deeper voices
 Thyroid gland is most common structure to be removed from the body
 Foramen cecum = origina of thyroid gland  cells migrate anteriorly
 Thyroglossal duct = narrow tube that attaches thyroid gland to foramen cecum during migration; develops from migratory path of thyroid during embryogenesis
 Vallate papillae =
 Superficial layer of cervical fascia = attaches sup’ly to occiput, mastoid process, and mandible and inf’ly to manubrium, clavicle, acromion, and scapular spine;
     contains SCM and trapezius m
 Fascia of infrahyoid mm = attaches sup’ly to hyoid bone, laterally to carotid sheath, and inf’ly to sternum and scapula (via omohyoid m); contains sternohyoid m ,
     sternothyroid m, omohyoid m, and thyrohyoid m (?)
 Prevertebral fascia = attaches sup’ly to base of skull and inf’ly to endothoracic fascia, Sibson’s fascia, and axillary sheath; contains longus colli m, scalene mm, deep
     back mm
 Cervical visceral fascia = pretrachial fascia, buccopharyngeal fascia, and carotid sheath  limit bacterial infection
 Pretrachial fascia = attaches sup’ly to hyoid bone and inf’ly surrounds trachea and continues to attach to aorta and pericardium; also attaches to thyroid gland
 Buccopharyngeal fascia = attaches sup’ly t base of skull and inf’ly follows esophagus down into the mediastinum to slowly fade away; attaches to post esophagus 
     slashing causes exposure to retropharyngeal space
 Carotid sheath = contains ansa cervicalis n, internal jugular v, common carotid a, vagus n  longus colli m lies post-med to sheath and cervical sympathetic chain lies
     ant-lateral to longus colli m b/w the m and carotid sheath
 Retrolaryngeal space - space b/w buccopharyngeal fascia and prevertebral fascia  possible route of infections spreading in retrolarygneal space from pharynx to
 Cervical sympathetic chain attaches sup’ly to sup cervical ganglion and inf’ly to sympathetic chain in thorax
 Thyrohyoid membrane connects hyoid bone to thyroid cartilage
 Lympatics of Neck = paracervical ring: occipital, retro-auricular, superficial parotid, buccal, submandibular, submental nodes; superficial cervical nodes; deep nodes:
     jugulo-digastric, upper deep cervical, jugulo-omohyoid, lower deep cervical nodes; jugular trunk (drainage of cervical lymph to venous system)

ROOT OF NECK              Where neck reaches
                          thorax and goes into
                           thoracic region
Thoracic inlet =           Bounded by 1st rib, body                                 Things passing through =
visceral connection b/w    of T1 vertebra, and                                      Viscera- esophagus, trachea,
neck and thorax            manubrium of sternum                                     apex of lung, apical cervical
                           and limited by clavicles                                 pleura (Sibson’s fascia); ant
                                                                                    longitudinal ligament
                                                                                    Muscles- longus colli, scalene
                                                                                    mm, infrahyoid (strap) mm
                                                                                    Nerves- recurrent laryngeal,
                                                                                    vagus, phrenic, nervous system
                                                                                    Vessels- subclavian a & v,
                                                                                    internal carotid a, internal
                                                                                    jugular v, brachiocephalic a
Anterior longitudinal
ligament – against ant
part of vertebral bodies
in post aspect of
thoracic inlet
Longus colli m –           Basilar part of occipital   Ant tubercles of C3-6        Acts to rotate the head to opp       Ventral rami of C2-6
against vertebra on        bone                        transverse processes         side and possible to flex the        spinal nn
either side in post                                                                 neck
aspect of thoracic inlet
Esophagus = most post      C6                          Passes thru sup and post
midline struct (right up                               mediastinum to get to
against vertebra) in                                   abdomen
thoracic inlet  b/w
trachea and vertebrae
Trachea = along            Lower neck                  Sup mediastinum –            Helps esophagus in swallowing;
midline in ant aspect of                               bifurcates into 2 primary    vitally important for bringing air
thoracic inlet; has U-                                 bronchii                     into lungs
shaped hyaline
cartilage rings and
smooth m along its post
Cupola = apex of lungs;    Rises above the first rib
covered by parietal        and clavicles and
pleura = cervical pleura   reaches into neck
or Sibson’s fascia
Scalenus anterior,         Ant = transverse            Ant = first rib ant’ly       Ant = rotating neck to opps side,    Ant = C4-6 cervical
medius, and posterior      processes of C3-6           Middle = first rib post’ly   *elevate 1st rib                     spinal nn
mm  middle and post       Middle = transverse         Post = second rib post’ly    Middle = side-bending of neck        Middle = ventral rami of
mm can often be fused      processes of C2-7                                        and *elevation of ribs during        cervical spinal nn
                           Post = transverse                                        forced inspiration                   Post = ventral rami of
                           processes of C4-6                                        Post = side-bending, *elevation      C7-8 spinal nn
                                                                                    of 2nd rib during forced inspir.
                                                                                    Act in breathing specifically
                                                                                    inspiration, holding the rib cage
                                                                                    up from the top
   If Sibson’s fascia is cut open during surgery e.g for thoracic outlet syndrome, it can cause pneuomothorax
   Parietal pleura also includes endothoracic fascia
   Subclavian a and brachia plexus pass b/w ant scalene and middle scalene  inflammation can cause compression syndromes
   Relative positions of visceral structures in midline of neck (post to ant) = esophagus, recurrent laryngeal nn, trachea

BONY THORACIC              Bony and muscular
CAGE                       struct which protect the
                           thoracic organs and
                           allow for lung fxn
Vertebral column                                                                 Forms a flexible support for the body & bony thoracic cage and indispensable
                                                                                 rotation at facet joints. Thoracic vertebrae have considerable rotation at facet
                                                                                 joints. Vertebrae separated by IV disk & cushioned by nucleus pulposus. Ribs
                                                                                 attach to vertebrae along jxn b/w 2 adjac vertebrae, except for 1st and last
Superior costal facet                                                            Vertebral articulation w/ head of own rib (all ribs)
Inferior costal facet                                                            Vertebral articulation w/ head of rib for vertebra below (rib 3-10)
Superior articular facet                                                         Make zygopophyseal joint with inferior articular facet
Inferior articular facet                                                         Make zygopophyseal joint with superior articular facet
Transverse costal facet                                                          Vertebral articulation w/ tubercle of rib (all ribs)
Inferior vertebral notch                                                         Forms intervertebral foramem w/ vertebra below
Costovertebral joint       Head of rib                 Sup & inf costal facets   Synovial joint w/ 2 synovial cavities
Costotransverse joint      Tubercle of rib (ribs 1-    Transverse costal facet   Synovial joint
                           10)                         of assoc. vertebrae
Costochondral joint        Sternal end of rib          Lateral end of costal     Cartilaginous joint
Costosternal joint         Costal cartilage (ribs 1-   Rib 1: manubrium          1st rib = cartilaginous joint
                           7)                          Ribs 2-7: sternal body    Ribs 2-7 = synovial joint
Sternoclavicular joint     Sternal end of clavicle     Manubrium and 1st         Synovial joint
                                                       costal cartilage
Radiate costosternal lig   Costal cartilage 2-7        Sternum (ant & post)      Reinforce costosternal joint
Intra-articular lig        Crest of head (b/w sup      IV disk                   Divides costovertebral joint into 2 synovial cavities
                           & inf facets on rib)
Radiate ligaments –        Ant margin of head of       Sides of bodies of 2      Strengthens ant part of costovertebral joint
Superior and Inferior      rib                         vertebrae and IV disc
                                                       b/w them  sup lig
                                                       goes to vertebrae above
                                                       and inf lig goes to own
                                                       vertebrae of rib
Costotransverse lig        Neck of rib                 Transverse process of     Strengthens ant aspect of costotransverse joint & post aspect of costovertebral
                                                       assoc vertebra            joint; limit joint movement
Superior                   Neck of rib                 Transverse process of     Limit joint movement
costotransverse lig                                    vertebral above it
Lateral costotransverse    Tubercle of rib             Tip of transverse         Strengthens post aspect of costotransverse joint; limit joint movement
lig                                                    process of assoc
   Features of Thoracic Vertebra – Lateral view = superior costal facet, superior articular facet, transverse process w/ transverse costal facet, spinous process, inferior
    articular facet, inferior vertebral notch, inferior costal facet, body; Superior view = lamina, spine, transverse process with articular facet, superior articular facet,
    superior costal facet, body, pedicle, vertebral canal
   T1 has a whole facet sup’ly and demifacet inf’ly; T2-8 have demifacets sup’ly and inf’ly; T9 has a sup demifacet; T10-12 have whole facets  whole facet receives
    whole rib head and demifacet receives ½ of rib head (semilunar shape) (????? –doesn’t correlate with chart above)
   Breathing depends on motion of ribs
   Spinal ligaments = ant longitudinal ligament, post longitudinal ligament, ligamentum flava, interspinous ligament, supraspinous ligament
   Position of thoracic spinous process in relation to other vertebrae = longest and spinous process of one vertebrae sits right above body of lower vertebra  no gab b/w
    adjac vertebrae
   Orientation of zygpophyseal (facet) joints and thoracic motion = Bony thoracic cage helps restrict rotation of thorax; zygapophyseal joints formed by the articular
    processes are oriented such they allow vertebral flexion, extension, lateral bending, and rotation
   Rib articulation with thoracic vertebral segments = attachment of rib to one superior and one inferior (of vertebra above) costal facet  overlies IV disk in junction; rib
    attaches to only one transverse costal facet  have synovial interaction of ribs with superior and inferior costal facets
   Intervertebral disk = nucleus pulposus and annulus fibrosis herniation of disk when stressed causes nerve impingement
   Rib structure = head (has 2 articular facets for both costal facets on ribs 3-10), neck, tubercle, angle (sharp bend), costal groove (where intercostal VAN lie), inferior
    margin, sternal articular end (attaches to costal cartilage)  has 3 synovial joints = 2 sets (costovertebral and costotransverse joint)
   Head of ribs 3-10 attach to 2 vertebra: the one they are numbered for (sup facet) and the one above it (inf facet)
   The heads of ribs 1,2, 11, 12 all attach to only one vertebrae b/c are at transitional regions, the one they are numbered for
   All 12 pairs of ribs attach to their own vertebra by a transverse tubercle on the rib, which articulates with the transverse costal facet
   Parts of sternum = manubrium (has jugular notch), body, xiphoid process (T7) manubirum and body are one continuous bony process but have structural diff (sternal
   Ribs end before sternum  connected via costal cartilage  not radio-opaque
   First costal cartilage attaches directly to manubrium: synchondrosis = cartilaginous connection; no joint  no synovial articuation; palpation hindered by clavicle
   Second costal cartilage attaches to via synovial cavity sternal angle (jxn of manubrium and body)  sternal angle = major landmark
   Costal cartilages 3-7 attach sequentially down body of sternum via synovial cavity, 7 th just above xiphoid process  ribs 2-7 synovial joints  allow small movement
    of ribs during respiration
   Costal cartilages 8-10 all attach to costal cartilages of rib above
   Ribs 1-7 = vertebrosternal ribs (true ribs), ribs 8-10 = vertebrochondral ribs (false ribs b/c no direct attachment to sternum); ribs 11-12 = floating ribs (no cartilage b/c
    no sternal attachment)
   1st ribs is highest, flattest, shortest = superlative rib
   Rib action: ribs move to allow thoracic cage to expand in deep inhalation; movements are for breathing, quiet breathing is diaphragm only, deep breathing involves
    increasing AP sectional diameter (ant-post diameter across thorax) and lateral diameter, using one of 3 mechanisms (pump handle, bucket handle, and caliper actions)
   Rib 1 is elevated or depressed by scalenes
   Ribs 2-5 have mostly pump handle operation, that is, they move up and down like a pump – rotating about transverse rotational axis (anterior-posterior expansion)
   Ribs 5-10 (5-7 mixed but bucket handle predominates) have bucket handle motion (rotation about ant-post axis), each rib (left and right) moving up laterally in
    inhalation, down in exhalation (lateral expansion)
   Ribs 11-12 open up as pincers on a caliper, expanding the thorax laterally (about sup-inf axis)  12th rib is small and stunted
   All ribs but 11-12 participate in expanding the vertical dimension, and ribs 4-7 will participate to some extent in both bucket handle and pump handle actions

THORACIC BODY              Muscular struct which
WALL MUSCLES               protect thoracic organs
                           and allow for lung fxn
External intercostal m     Borders of adjac ribs                                  Primary inspiration elevates        Intercostal nn of             Intercostal aa of
& membrane  mm            extends ant’ly to                                       rib below                            corresponding spaces          corresponding spaces
absent ant’ly (end @       costochondral jxn and
costal cartilage) and      post’ly to rib tubercle
replaced by membrane;        Membrane = from
fibers run sup-lat to inf-   costochondral jxn to
med in ant space             sternum
Internal intercostal m &     Attached to borders of                                Primary expiration  depresses      Intercostal nn of           Intercostal aa of
membrane  mm                adjac ribs  extends                                  rib above                           corresponding spaces        corresponding spaces
absent post’ly (end @        from angle of rib post’ly
rib angles) and replaced     and sternum ant’ly
by membrane; part b/w        Membrane = continues
cartilage is                 layer post’ly b/w angle
interchondral                and tubercle of rib
(parasternal); fibers run
from inf-lat to sup-med
Innermost intercostal                                                              Act w/ internal intercostal mm      Intercostal nn of           Intercostal aa of
mm & membrane                                                                     to depress ribs during expiration   corresponding spaces        corresponding spaces
weak ant’ly and
post’ly, strongest in
laterally; minute to
absent at highest
thoracic levels and
become progressively
stronger inf’ly
Transversus thoracis m       Post surface of lower       Internal surfaces of      Depresses costal cartilages         Intercostal nn of           Intercostal aa of
                             sternum and xiphoid         costal cartilages 2-6     relative to sternum during          corresponding spaces        corresponding spaces
                             process                                               expiration
Subcostal m  only in        Internal surface of lower   Sup borders of ribs 2-3   Post & inf: holds & depresses       Intercostal nn of           Intercostal aa of
lower post part of           ribs near their angles                                ribs during expiration; elevate     corresponding spaces        corresponding spaces
thorax; span 2-3 rib                                                               ribs (?)--Moore
levels; will be found
deep to ribs
Serratus posterior                                                                 Deep inspiration  elevate ribs
superior mm
Serratus posterior                                                                 Deep inspiration depress ribs
inferior mm
Thoracoabdominal                                                                   Primary respiration  contracts     Phrenic n (motor all over   Superior surface:
diaphragm muscle,                                                                 (depresses) to enlarge thoracic     and sensory to central      superior phrenic aa from
central tendon, crus,                                                              cage in inspiration; contracts      part); intercostal nn and   thoracic aorta,
hiatus; critical to                                                                slightly to dec thoracic pressure   subcostal n (T12) provide   musculophrenic and
breathing, attached                                                                pulls down on pleural cavity       sensory to peripheral       pericardiophrenic aa
peripherally to lowest                                                             space to create neg pressure to     parts                       from internal thoracic aa
parts rib cage; center is                                                          pull air into lung  pressure is                                Inferior surface: inferior
sucked up into thoracic                                                            relieved when air enters the lung                               phrenic aa from
cavity so it forms a                                                               (relax diaphragm to exhale                                      abdominal aorta
dome                                                                               quietly elastic forces w/in
                                                                                   lung will cause the lung to
                                                                                   slightly collapse, causing air to
                                                                                   leave the lung); used when inc
                                                                                   intra-abdominal pressure in
                                                                                conjunction w/ rectus abdominis
                                                                                m and lateral abdominal wall
                                                                                mm; inc’ed abdominal pressure
                                                                                is also transmitted thru the
                                                                                diaphragm to the lungs in forced
Muscular diaphragm          Sternal: attach to post
3 parts = sternal, costal,   aspect of xiphoid
lumbar                       process (ant’ly)
                             Costal: internal surfaces
                             of costal cartilages 7-12
                             and adjoining ribs on
                             each side (laterally)
                             Lumbar: L1-3 (post’ly)
Central tendon of                                                               Has opening for IVC
diaphragm – has no
bony attachedment
Crura of diaphragm –         Arise from the ant                                 Right crus forms esophageal
musculotendinous             surfaces of the bodies of                          opening; left and right crura
bundles (post                L1-3, the ant                                      form aortic hiatus;
attachments); right crus     longitudinal ligament,
more extensive than left     and IV discs
Hiatus of diaphragm                                                             Opening b/w thorax and
                                                                                abdomen for esophagus, aorta,
                                                                                & IVC to pass thru into
Quadratus lumborum                                                              Secures bottom ribs
Medial arcuate lig –       Fascia covering psoas                                Give rise to lumbar part of
aponeurotic arch           major and quadratus                                  diaphragm; unites left and right
                           lumborum                                             crura at ant part of aortic hiatus
Lateral arcuate lig –      Fascia covering psoas                                Give rise to lumbar part of
aponeurotic arch           major and quadratus                                  diaphragm
 Intercostal v, a, & n travel along costal groove in that order from sup to inf = VAN  protected by inferior margin of rib
 Mm of thoracic cage maintain tension and spacing of ribs, and maintain overall tightness of the thoracic wall
 Primary resp fxns fall to diaphragm in inspiration  expiration is largely passive, but may be assisted by abdominal pressures as well
 Thoracoabdominal diaphragm is traversed by aorta, esophagus, inferior vena cava, thoracic duct, sympathetic trunk; overlies several mm crossing behind it (Psoas
    major, quadratus lumborum)
 When relaxed, the diaphragm is sucked up into thorax as air leaves lung; when contracted, mm pulls downward on overall diaphragm
 Aperatures of diaphragm: T8 level = hiatus for IVC (in right dome of thoracoabdominal diaphragm); transmits IVC only; T10 level = esophageal hiatus; transmits
    esophagus and ant/post vagal trunks; T12 level = aortic hiatus; transmits descending aorta and thoracic duct
 Forcible inhalation: to inhale forcibly req both diaphragm and chest wall mm; scalene mm pull upwards; ext intercostal mm most active in inspiration & int intercostal
    mm most active in expiration; quadratus lumborum holds bottom end down; negative pressure applied will cause the air to enter the lung; note contribution of serratus
    posterior mm and even serratus anterior (if shoulder is fixed)
 Forcible expiration: air passively flows out of lungs when diaphragm is relaxed; to force air out (eg blowing up a balloon) thoracic cage is forced closed, with int
    intercostals most active this time; additional force may come from abdominal wall mm (rectus abdominis, abdominal obliques) pulling the chest wall down and
    compressing abdominal viscera to force the diaphragm higher.
   Inspiration = diaphragm + ext intercostal mm (quite); diaphragm + ext intercostal mm + SCM + scalenes (forced)
   Expiration = none for quiet expiration b/c cone passively by elastic recoil of lung tissue; (forced) int intercostal mm + innermost intercostal mm + anterior abdominal
    wall mm (compression of viscera against diaphragm)
   Endothoracic fascia = lines internal aspect of mm and bones (pleural cavity); covers the superior thoracic side of the diaphragm
   Parietal pleura = innermost layer of the thoracic wall but is the external layer of the pleural sac; covers most of thoracic wall, superior side of diaphragm mediastinum;
    held in place by endothoracic fascia (but easily detachable)  costal pleura covers lungs only
   coartation of aorta = congenital heavy narrowing of aorta below ductus arterious  cuts off supply to lower extremities so find higher bp in upper body  anastomoses
    can supply lower extremities

 Lymph produced in lungs first enters pulmonary nodes w/in lung tissue and progressive passes up the trachea thru bronchopulmonary, tracheobroncheal, and
   paratracheal nodes  eventually joins lymph from heart and mediastinum in bronchomedistinal trunks, which empty into respective venous angle
 Bronchial tree = primary bronchi  secondary bronchi  tertiary bronchi  quaternary bronchi  etc
 Cancer cells can get trapped in bronopulmonary nodes and go to tracheobroncheal nodes to paratracheal nodes and ultimately to bronchomediastinal trunk
 2 divisions of autonomic NS = sympathetic (fight or flight) and parasympathetic (secretomotor)
 autonomic NS is critical to lung fxn: sympathetic = relaxes smooth mm to dilate airways; parasympathetics = secretion of mucus and other fluids
 autonomic NS --> visceral afferent = sensory & efferent = sympathetic and parasympathetic motor
 Viscera sense pain in terms of pressure etc but brain doesn’t recognize it as pain of the internal organs recognized as pain of the dermatome where the organ is
   located b/c afferent n info goes to spinal cord to brain = referred pain
 Referred Pain: sympathetic =Pain in viscera follows the sympathetic axons back to the sympathetic chain ganglia, passes through the white rami communicantes with
   the preganglionics and into the spinal N; then pass into the dorsal root and axons pass into the dorsal horn – here they synapse on the axons that detect pain (somatic
   Nervous system) from skin, M, and bone
 Preganglionic cell bodies loc in CNS (brainstem or spinal cord)  preganglionic n axons that leave CNS are myelinated and synapse w/ postganglionic cells in
   ganglion  postganglionic axons go to target organ (gland or mm) and synpase on effector cell
 Ascending & descending fibers: some fibers of autonomic NS will ascend or descend one or more levels, so that the pregang axons can synpase in a diff ganglion
   above or below the specific level they originate at
 Horner’s syndrome results in constricted eye b/c symp NS responsible for pupil dilation
 Sympathetic fxn = dilate pupils; inc heart rate; dilate coronary blood vessels; bronchodilation and reduced secretion; inhibit peristlsis; constrict blood vessels to GI tract
 Sympathetic chain ganglia follow along vertebra  symp pregang axon only found in spinal T1-L2 levels, never above or below (therefore no white rami above T1)
 Symp pregang motor axons leave spinal cord thru ventral root, pass thru spinal n ventral rami and enter ganglia via white (myelinated) rami and to synapse w/ postgang
   cells in ganglia (at same or other levels in paravertebral ganglia or exit splanchinic opening to synapse in prevertbral ganglia)  Postgang axons leave ganglia via gray
   rami of paravertebral ganglia and pass thru ventral or dorsal rami or exit prevertebral ganglia to effector site
 Sympathetic: pregang NT = Ach & postgang NT = NE; Parasympathetic: pregang and postgang NT = ACh
 A lot of asthma inhalers contain epinephrine to help relax smooth mm of lungs sympathetics relax smooth mm to dilate airway and relax trachea to open airway
 Cervical and lumbar sympathetics: to reach the cervical ganglia, pregang axons from T1-4 or so will ascend the chain into the neck, to synapse on the inferior, middle,
   or superior cervical ganglia; to reach the lumbar and sacral levels, some pregang axons from the lower part of the chain, about T11-L2 or so, will descend the chain into
   lower lumbar and sacral levels  all pregangs to cervical come from upper thoracic levels eliminate all input to cervical levels if slash chain b/w T1 and inf cervical
   ganglion b/c no pregangs above T1
 Sometimes T1 and inf cervical ganglion are fuse = stellate ganglion
 Cardiac brs leave sup, middle, and inf cervical ganglia; ansa subclavia brs from middle cervical gang, loops around subclavian a, and connects to inf cervical ganglion
 Autonomic axons to thoracic viscera, such as heart and lung, will have pregans from T1-4 levels (sometimes T5; the postgangs will leave the ganglia to travel
   separately (no in concert w/ other vessels or nn) to reach the viscera; brs also come from the cervical chain ganglia, although their pregangs still originate from T1-4
 Sympathetic pregangs from T5 and below will go to abdominal viscera; the pregang axons will bypass the ganglia and head for the abdomen in separate nn called
   splanchnic nn; 3 splanchnic nn in thorax = greater splanchnic (T5-9); lesser splanchnic (T10-11), and least splanchnic (T12)
   Splanchnic nn will synapse in the abdomen on various ganglia that are located on the ant surface of the aorta; the ganglion is in assoc w/ and named for the vessel that
    leaves the aorta that it sits next to  major ones = celiac, aorticorenal, superior mesenteric, and inferior mesenteric ganglion
   Sympathetic postgang axons then follow the named artery and its brs to the organs supplied by that aa (abdominal sympathetics)
   Parasympathetic fxn (Secretomotor system) = constrict pupils; dec heart rate and constrict coronary blood vessels; constrict bronchi and promote bronchial secretion;
    stimulate peristalsis; secrete digestive enzymes after eating; sexual arousal (erection)
   Parasympathetics = CN 3,7,9,10; sacral segments 2,3,4craniosacral (eating, elimination, reproduction)  except in heat, all nn are long pregang; ganglia and
    postgang (short) cells are near effector organ
   Parasympathetics: parasymp pregang axons arise from the brainstem (medulla oblongata) and travel with the vagus n (CN X = all pregang vagal plexuses extend
    down thru diaphragm with esophagus and into abdomen); they synapse in minute ganglion w/in wall of thoracic or abdominal organ they innervate therefore postgang
    axons only exist only w/in wall of individual organ

LUNGS & PLEURAL             Lungs bring oxygen into
CAVITY                      body
Pleural cavity –            Extent of cavity: sup =     Lateral = ribs; ant =        Allows smooth friction free
potential space (filled     apex of lung; inf =         sternum; post = ribs         movement against ribs for
w/ small amount of          diaphragm; medial =                                      expansion of lungs
fluid); lined by pleura     mediastinum
Right lung - horizontal     Apex ascend above           Base of lung at level of     Fill with air to bring oxygen into   Vagus n                   Pulmonary aa & vv
fissure follows rib 4;      level of clavicle and rib   rib 6 ant’ly --> base sits   bloodstream, release of carbon       (parasympathetics) &
oblique fissure laterally   1 into root of neck         on diaphragm; pleural        dioxide into atm, and regulation     sympathetic fibers from
found at rib 4 and          (reaches thoracic inlet)    cavity continues to rib 8    blood pH by carbon dioxide           symp trunk
descends medially to                                    ant’ly (midclavicular        control
meet rib 6 at                                           line)
midclavicular line;
larger than L lung
Left lung - from            Apex ascend above           Lower limit at rib 6         Fill with air to bring oxygen into   Vagus n                   Pulmonary aa & vv
midline there is a          level of clavicle and rib   ant’ly --> base sits on      bloodstream, release of carbon       (parasympathetics) &
cardiac notch starting at   1 into root of neck         diaphragm; pleural           dioxide into atm, and regulation     sympathetic fibers from
costal cartilage 4 and      (reaches thoracic inlet)    cavity continues to rib 8    blood pH by carbon dioxide           symp trunk
arching over not quite                                  ant’ly                       control
to midclavicular line;
smaller than R lung b/c
heart skews to left
Trachea  bifurcates                                                                                                      Sympathetic and
(unequally) at Carina                                                                                                     parasympathetic NS
into R & L primary
bronchi; has u-shaped
rings w/ m post’ly
Bronchi  L primary         Carina of trachea           Lungs: primary              Passageway for air into lungs       Sympathetic NS; vagus n   Bronchial aa  left aa
bronchus travels more                                   secondary  tertiary        aspirated bodies more often          (Parasym NS)              arise from thoracic aorta
horizontally to get over                                etc divisions                follow the R primary bronchus                                  and right aa come from
heart; R primary                                                                     to the R lung following gravity                                sup post intercostal aa
bronchus travels more                                                                to the inf parts
vertically downwards;
secondary bronchi
define lobes; tertiary
divisions define
segments (further
subdivision of lung)
Parietal pleura (costal,                                                             Simple squamous epithelium           Sensitive to somatic pain
diaphragmatic,                                                                       (mesothelium) lining pleural         (conscious, localizable)
mediastinal, cervical                                                                (pulmonary) cavity                    intercostal nn, phrenic
(cupula)) -->                                                                                                             nn
continuous with
visceral pleura at hilum
of lung but separated
by cavity
Endothoracic fascia –                                                                Separates costal pleura from
thin extrapleural layer                                                              thoracic wall
of loose CT (inside of
rib cage)
Visceral pleura – fused                                                              Invests lungs, including surfaces Vagus n; No sensation          Bronchial aa
to all surfaces of lungs                                                             w/in fissures
recess (L & R) –
extension of pleural
cavity (beyond size of
lungs) into narrow
space b/w ribs and
Costomediastinal recess
– located ant’ly over
Pulmonary ligament =                                                                 2 layers of mesothelium w/ little
visceral ligs that are                                                               bit of CT b/w where its going
part of internal organ                                                               from being parietal to visceral
 Lungs fxn b/c of the pleural cavity --> Lungs very close to parietal pleura
 All body cavities are line by mesothelium, which lies on a thin sheet of CT --> Squamous epithelium + CT = pleura, peritonieum, pericardium --> special names
 Visceral pleura – not seen but can see the effect – give shine to lungs
 B/w lungs is where heart exists in mediastinum --> part of mediastinum is the peritoneum cavity (?)
 Excess pleural fluid in pleural inflammation (pluerosy), blood, or protein can collect in pleural spaces not containing any lungs --> need x-ray to determine level and
     remove via thoracocentesis3 pleural spaces w/o lungs = L & R costodiaphragmatic and costomediastinal recess
 Hilum = where vessels go into and out of lungs and bronchi enter  Right= bronchus is post; pulm a is ant, pulm vv are ant and inf; Left = bronchus is pos, pulm a is
     sup, pulm bb are int and inf
 Costal pleura = covers internal surface of rib cage; diaphragmatic pleura = covers superior surface of diaphragm; mediastinal pleura = covers lateral part of
 Concepts of R. Lung: inf lobe fills in large space adjac to vertebrae and ascends much higher than middle lobe, so has great volume; superior lobe is large ant’ly but
     smaller post’ly; middle lobe is smallest, only found ant’ly; hilus – bronchi is most post, aa tend to be sup, vv are more inf; bronchial aa on post surface of bronchus -->
     they supply bronchi and such w/ oxy blood
 Concepts of L lung: many of the same generalization hold true for l and r lung; b/c L ventricle of hear encroaches on L pleural cavity, there is no middle lobe; have
     small lingua that is part of superior lobe; heart leaves an open semicircle cardiac notch in lung; pulmonary aa sup and vv inf
 Vv carry blood to heart and aa carry blood away from hear so can have either oxy or deoxy blood in vv or aa
 Visceral impression in R. Lung = R subclavian a groove, SVC groove, azygos v groove, R atrial impression, esophageal impression, diaphragmatic impression
   Visceral impression in L. lung = trachea and esophagus impression, aortic impression, esophageal groove, L subclavian a groove, brachiocephalic v groove, cardiac
    impression, diaphragmatic impression
   Lingual forms the cardiac notch
   Concept of lung fxn: breathing – as diaphragm pulls down on pleural cavity, it causes the pressure in the pleural cavity to drop (neg pressure); it can only be
    compensated by air entering the lung; to exhale, internal elasticity of the lung causes it to contract automatically – relaxing the diaphragm causes air to leave, and the
    diaphragm is passively drawn upward into the pleural cavity
   Lung sounds: faint sounds = require practice to recognize; most superior – apical (heard above clavicle); anterior – right = superior (heard above 4th rib) and middle
    (heard below 4th rib) lobes, divided by 4th rib & left = superior lobe and lingula (heard b/w 5 th and 6th ribssounds in lingula may be obscured by heart sounds); lateral
    and posterior – easiest to hear inferior lobe  rale = noise in lungs
   Fluid collection: in pleurisy (inflammation of pleural cavity), fluid occasionally builds up; this can be removed for analysis by puncture w/ a needle; in an erect patient
    (standing or sitting up), a needle can be placed in the intercostal space 1-2 spaces below fluid level (ascertained by x-ray) when sitting erect (don’t go below 8th space
    b/c could puncture diaphragm or hit liver); under no circumstances should you allow the lung to be punctured b/c that would cause a pneumothorax
   Thoracocentesis = to collect serous pleural effusion from pleural cavity
   3 secondary bronchi on R lung (sup, middle, inf lobes)  Segmental bronchi (tertiary divisions): sup lobe= apical, post, ant; middle lobe = lateral, medial; inf lobe =
    sup, ant basal, medial basal, post basal, lateral basal  total = 10 segments
   2 secondary bronchi on L lung (sup & inf lobes) Segmental bronchi: sup lobe = apicoposterior, ant, sup lingual, inf lingual; inf lobe = sup, anteriomedial, lateral
    basal, post basal total = 8 segment
   Infections of lung: lung infection usually start I none segment, being aspirated (heavy particles usually follow gravity into the lung); persons who stand or sit erect most
    of the time, this will often go inf; persons bedridden (supine), the infections will often follow gravity and go to the post positioned segments of lung; infection generally
    spread first to adjac segments of the same lobe before going to other lobes
   Pneumothorax= lung is elastic so any air in pleural cavity will cause it to collapse; air can come from ext puncture of thorax, but more commonly will arise from a hole
    in the lung itself (usually spont, especially in emphysema b/c a lot of space b/w alveoli)
   Oblique fissure = divides left lung into sup and inf lobes and right lung divides inf lobe from sup & middle lobes
   Horizontal fissure = divides sup and middle lobes

MEDISTINA                  Space b/w the two           Limits = thoracic inlet,
                           lungs, b/w sternum and      manubrium, sternal
                           vertebrae, housing the      angle, T4 vertebra, body
                           heart and great vessels,    of sternum, xiphoid
                           and etc.                    process, diaphragm
Superior mediastinum       Above sternal angle                                     Contains (ant to post) thymus,
                                                                                   brachiocephalic vv leading to
                                                                                   SVC, vagus nn, cardiac plexus,
                                                                                   & phrenic nn, arch of aorta and
                                                                                   brs, trachea, & (sup) esophagus
Inferior mediastinum =     Below sternal angle                                     Contains pulmonary trunk and L
ant, middle, & post                                                                primary bronchus
Anterior mediastinum       B/w pericardium &                                       Contains mostly fatty tissue and
                           sternum                                                 some lymph nodes, internal
                                                                                   thoracic a
Middle mediastinum                                                                 Contains pericardial cavity and
                                                                                   its contents (pericardium, heart,
                                                                                   ascending aorta, pulm trunk)
Posterior mediastinum      B/w pericardium &                                       Contains descending aorta,
                           vertebrae                                               esophagus, azygos v,
                                                                                   hemiazygos v, thoracic duct, L
                                                                                    primary bronchus
Ligamentum arteriosum      Located at sternal angle
= embryonic remnant
Thymus – sits on top of                                                                                                                                Ant brs of internal
heart in sup                                                                                                                                           thoracic a; inf thyroid v
mediastinum; very
active in childhood but
lymphocytes replaced
by fatty tissue after
puberty due to
involution = change in
mass of organ
Esophagus – behind         Post to aorta and           Stomach                                                            Vagus n                      Esophageal br of
trachea & on top of        trachea, stays medial as                                                                                                    descending aorta & post
vertebra; surrounded by    aorta arches to left;                                                                                                       intercostal aa
vagal plexus; travels      becomes ant to aorta as
thru sup and post          the aorta moves near the
mediastina                 midline at diaphragm &
                           thru the esophageal
                           hiatus of diaphragm
   Sternal angle (angle of Louis)= landmark for division b/w superior and inferior mediastinum; site for arch of aorta (arches over the angle), bifurcation of trachea, &
    bifurcation of pulmonary trunk (below the angle); where 2nd costocartilage attaches  plane crosses thru b/w T4 & 5 IV disk space
   Venous angle – where lymph trunks enter into venous system
   Sympathetics: Visceral afferent = sensory fibers from visceral organs --> 2 ways of getting info = 1. Chemical/physical = pressure in aorta, ph in blood stream, related
    to way body is fxning—sensations travel with parasymp; vagus n. pain fibers travel with sympathetics
   Pain fibers go directly to CNS --> travel with white rami, to spinal n, to spinal cord --> no room in brain for this info so pain of visceral organs is assoc with skin of that
    dermatome = referred pain --> heart pain assoc with t1-t4 dermatome; 2.
   Vagus n carries all of parasymp fibers to the heart – gives upper and lower cardiac brs = pregang parasymp fibers that synapse w/in cardiac plexus to give very short
    postgang fibers; Pregang n fibers are very long bc go directly to organ and synapse on organ w/ very short postgang fibers w/in organ

SUPERFICIAL                HEART
 Pericardium  double-walled fibroserous sac that encloses the heart and the roots of its great vessels; located in the middle mediastinum
 Pericardial cavity & fluid  contains heart & serous fluid that allows for constant function w/ minimum friction; sits on central tendon of diaphragm
 Parietal pericardium = fibrous + serous pericardium  parietal serous and visceral serous are continuous around roots of great vessels (surrounds veins independent of
   arteries) so pericardium attached to heart in various areas but other than that the heart is free to move
 Parietal fibrous pericardium  parietal region of fibrous tissue sandwiched b/w mediastinal pleura and parietal serous pericardium; surrounds whole outer part of heart
 Parietal serous pericardium  mesothelium = simple squamous epithelium + CT
 Visceral serous pericardium  mesothelium, resides on visceral surface
 Transverse sinus = hole in pericardium b/w the origins of the great vessels  separates great arteries from veins (although they lie adjacent to each other); if open
   pericardial sac anteriorly, can put finger thru sinus posterior to aorta and pulmonary trunk
 Oblique sinus = wide, pocket-like, blind-ended (where pericardium attaches to heart) recess in the pericardium posterior to the base of the heart  bounded laterally by
   the pericardial reflections surrounding the pulmonary vv (L & R) and IVC and posteriorly by the pericardium overlying the anterior aspect of the esophagus
 Coronary sulcus = groove that separated right atrium from right ventricle; goes all the way around the heart
 Interventricular groove = separates left and right ventricles; interventricular septum is deep to this
   Heart location borders  superior limit of mediastinum = 2nd intercostal space adjacent to sternum, sternal angle (everywhere else the pericardium parallels the heart
    position); superior limit of heart = 3rd intercostal space adjacent to sternum, costal cartilage of rib 3; apical limit = left 5 th intercostal space just medial to L.
    midclavicular line; inferior limit = xiphisternal jxn (diaphragm attaches at xiphosternal junction, where heart rests on)
   Heart chambers (externally) & subdivision and major associated vessels = right atrium (superior to right ventricle), right auricle (tab off of right atrium), right ventricle
    (most anterior part), left atrium (most posterior part of heart, superior to left ventricle), left auricle (tab off of left atrium), left ventricle (right ventricle); SVC & IVC
    associated with right atrium, pulmonary trunk & arteries associated with right ventricle, pulmonary veins associated with left atrium, aorta associated with left ventricle.
   Plane of heart base runs diagonally from left superior limit at 3 rd costal cartilage to right inferior limit at xiphosternal junction
   Valve locations = located under sternum  aortic = superior to plane of heart base to the right side; pulmonary = superior to plane of heart base to the left side; mitral =
    inferior to plane of heart base to the left side; tricuspid = inferior to plane of heart base to the right side
   Valve sounds of superficial heart = heard at points of turbulence and not at location of valves b/c they close quietly  sound echos along base line; aortic = heard over
    right 3rd costal cartilage (2nd intercostal space); pulmonary = heard over left 3 rd costal cartilage (2nd intercostal space); mitral = at apex of heart (left 5 th intercostal
    space); tricuspid = above or below 4th costal cartilage (left 3rd or 4th intercostal space)
   At each site, 2 heart sounds can be heard (lub,dub)  lub = AV valve closure (mitral, tricuspid); dub = semilunar valve closure (aortic, pulmonary); for murmurs,
    location of loudest murmur sound is for problematic valve associated with that site
   Great arteries = aorta and pulmonary trunk; Great veins = superior & inferior vena cava and pulmonary vv
   Coronary vasculature = right coronary artery (SA nodal br, conus br, marginal br, posterior intervetnricular a); left coronary artery (anterior interventricular a,
    circumflex a, marginal a); great coronary v, middle cardiac v, small cardiac v, coronary sinus, anterior cardiac veins
   SA node br goes behind R auricle to SA node at jxn of sulcus terminalis comes off of R coronary 50% of time. Conus br goes to upper part of R ventricle towards
    pulmonary trunk. R marginal br follows along inferior margin of R ventricle. R coronary a lies in R coronary sulcus and continues to back side of heart where it gives
    off a posterior interventricular br & anastomoses w/ circumflex a.
   L coronary a comes off of aorta behind pulmonary trunk and brs quickly. Circumflex br goes around towards posterior side along L coronary sulcus and gives off ant &
    post brs (post a of left ventricle). L marginal a follows left radiologic margin of heart. Ant interventricular a is very large and important b/c supplies L and R ventricles
    and 75% of interventricular septum, which is involved w/ the conducting system of activating ventricles during contraction loss of supply = loss of great deal of mm
    mass which could lead to fibrillation.
   Right dominant pattern (most common) = R coronary a supplies posterior interventricular a
   Left dominant pattern (less common) =
   Other heart patterns (e.g. balanced pattern; rare) = Balanced  both sides supplied by their own arteries so there is no posterior interventricular a

 Starts out as a tube  bends over  forms 4 chambers
 Heart develops during first 8 wks of life. It begins to beat on day 22. It changes its structure and shape as the heart is still working.
 Lungs do not fully inflate until birth. Lungs are not being used to oxygenate blood while embryo is in the womb
Origin of the heart (day 18-22)
 Starts from mesoderm rostral to the oral plate, adjacent to the septum transversum
 At about day 18, the heart develops from blood islands associated w/ the septum transversum, developing into endocardium (which is simple squamous epithelium,
    similar to endothelium). This forms 2 heart tubes, a left and a right one, which fuse into a single tube.
 Formation of the heart tube: the cardiogenic blood spaces fuse into a presumptive heart. Mesoderm in the developing aortic arches develop into branchial arches,
    starting w/ AA 1 and at the venous end the mesoderm begins to form a series of veins from a relatively, poorly defined mass referred to as the angioblastic plexus.
    Cardiogenic mesoderm differentiates into myocardium and cardiac jelly on the outside of the heart, while the endocardium continues to line the inside of the heart.
    Neural crest develops into aortic root and parasympathetic ganglia.
 The pericardial cavity and its mesothelium lining, forms from mesoderm in the adjacent to the developing heart, as discussed in core embryo.
 Day 21-22: venous end receives blood from yolk sac, which are the body’s first functional veins. Arteries begin to pump to the head, via early aortic arches.
Development of heart (day 22-26)
 Inversion of the heart tube: growth of the neural tube pulls the oral plate and septum transversum first superiorly, then anteriorly until the heart eventually is flipped
    Left and right heart tubes fuse. At about 21 days, the 2 heart tubes fuse along the midline. As the embryonic head grows, the tube expands, fuses more in the middle,
     and folds over.
 Bending of the heart tube: the heart will grow faster than its associated pericardial cavity, causing it to bend into a loop in a clockwise direction (when seen facing the
     anterior surface of the embryo). It bends into an ―S‖ shape. The new shape has a large bulge, or bulboventricular loop, to eventually divide into 2 chambers. The atria
     are fusing into a single cavity. Bending assures we will get 4 chambers and occurs at a particular degree = left bending
 Formation of the transverse sinus from the dorsal mesocardium.
 Anatomy of the early heart: aortic sac, truncus arteriosus, bulbis (conus) cordis, ventricles, bulboventricular loop, atria, sinus venosus.
 Shift of the major systemic vessels: systemic arteries shift to the left w/ the development of the aorta; systemic vv shift to the right as the opening for the sinus venosus
     moves to the right side of the atrium.  systemic vv move to drain into right side of heart, and systemic arteries arise from left side of heart
 Day 23 = coordinated beating and blood pumping
 Atria fuse and expand by incorporating veins (pulm vv on left, sinus venosus on right) into atrial walls. The rough-walled part of atrium is from embryonic atrium and
     smooth-walled (sinus venerium) part is from venous origin
 In its earliest development, the heart is suspended by a dorsal mesocardium. As the heart grows and bends, a hole in this mesocardium develops = tranverse sinus 
     continues to develop as the dorsal mesocardium stretches during fetal period
Partitioning of the heart (day 28-35)  items 1-4 occur simultaneously
 1. Endocardial cushion: separates the atria from the ventricles, provides a central point for the left-right separation of the heart chambers. The superior and inferior EC
     will fuse on day 42 to become the single septum intermedium, leaving behind 2 openings from atria to ventricles, the atrioventricular canals. Endocardial cushion
     develops in the center from anterior and posterior simultaneously and forms a pillar down the middle  acts as an anchor for atria and ventricles to divide
 2. Atrial septation
 Foramen primum: original communication b/w L & R atria. Closes completely
 Septum primum: closes foramen primum. B/c there must be blood flow (deoxy blood) from right to left atrium, another hole arises in the septum primum (below).
 Foramen secundum: secondary interatrial passage (essential for allowing blood to get into left atrium, and therefore left ventricle)  behind the septum secundum
 Septum secundum: forms valve that only permits blood to flow only from right atrium to left atrium, not the reverse
 Foramen ovale: space w/in the arch-like opening of the septum secundum; in coronal view, it will sit b/w septum secundum and endocardial cushion (septum
     intermedium)  behind septum primum
 As heart starts to divide, oxygenated blood will be sent to the aorta and deoxygenated blood will be sent to the SVC & IVC.
 Truncus arteriosus forms the interventricular septum, aorta, and pulmonary trunk
 90% of venous blood comes into R atrium, yet 50% leaves via L ventricle. Ergo, much of blood entering R atrium must go to L atrium. Therefore, there must always be
     a connection. As foramen primum shrinks, a second foramen connecting the 2 must form
 The atria leaves a space, the foramen ovale, for blood to go from the IVC to the L atrium.
 3. Ventricular septation
 Muscular interventricular septum: arises from interventricular septum
 There is an interventricular foramen b/w the left and right ventricles during the early (5 th wk) development of the heart. This is finally closed over by a complex
     arrangement (below).
 As the septum intermedium and spiral (aorticopulmonary) septum of the truncus come together with the muscular septum, the first two membranes (septum
     intermedium & spiral septum) fuse to contribute to the membranous interventricular septum.
 Valve formation: arises primarily from tissues associated with the developing muscular wall. Programmed cell death causes the valvules to develop in conjunction w/
     the chordae tendineae and papillary mm, alldeveloping simultaneously in a well-choreographed process.
 The interventriuclar septum closes, and the membraneous part arises from the endocardial cushion.
 4. Spiral septation of the bulbus
 Mechanism: swellings arise from differential growth of the wall of the bulbus and truncus, which complete a 180 degree turn of a spiral. Around the junction of the
     truncus and bulbus there are a set of four swellings, which will form the basis for later development of the pulmonary and aortic valves.
 Separation of the aortic from pulmonary blood flow from a common truncus via spiral septum. The spiral septum separates the blood flows in the truncus and bulbus,
     eventually not only dividing the tubes down the middle but completely separating the 2 major arteries, aorta and pulmonary trunk.
 Merges w/ the interventricular septum. The spiral septum merges inferiorly with the developing muscular interventricular septum, ensuring the vessels are in continuity
     w/ the ventricles.
   Spiral septum is behind interventricular septum
   R ventricle is ant  pulm trunk has to arise from the post part of the aortic sac. The L ventricle is post  aorta has to arise from the ant part of the aortic sac
   SVC carries low oxygen blood from the head and upper limb
   The final result of the spiral septum is an aorta and pulm trunk that twist around each other
   IVC carries high oxygen blood from umbilical v
   Blood is routed thru R atrium: SVC blood goes directly thru R atrium to R ventricle; IVC blood goes thru foramen ovale to L atrium and thence to L ventricle

Development of the arterial system:
 Aortic sac = receives blood from truncus arteriosus, and distributes it to all of the aortic arches
 Aortic arches = found in the branchial arches, sends blood to the dorsal aortae of the head, the left aortic arches to the left dorsal aorta of the head, the right aortic
    arches to the right dorsal aorta of the head.
 Dorsal aorta = the two dorsal aortae (L & R) fuse past the 6 th aortic arches to form the single dorsal aorta of the body, most of which becomes the descending aorta in
    the thorax and, farther down, the abdomen.
 Intersegmental arteries = arteries branching off of the dorsal aorta which segmentally supply parts of the periphery. Note that the 7 th intersegmental becomes the
    subclavian and parts of the axillary artery.
 Vitelline arteries = supply the yolk sac. Its main branches become celiac, superior mesenteric and inferior mesenteric arteries.
 Umbilical arteries = arise from the internal iliac arteries. All fetal blood going to the placenta arise from the two umbilical arteries.
Formation of the great vessels and fat of each aortic arch:
 Great vessels = pulmonary trunk and aorta arise from aortic arches; there are 5 aortic arches that develop in the human embryo (1,2,3,4, &6); of these arches 1 & 2
    involute early and leave no major remnants.
 The head has 2 dorsal aorta that fuse into a single descending aorta (dorsal aorta of body) in the neck region (beyond aortic arches)  blood to dorsal aorta of head and
    arches comes from aortic sac; vitelline and umbilical aa brs off of the single descending aorta & arches connect b/w dorsal aortae of head & aortic sac
 Arch 1, bilaterally  maxillary artery. Serious questions still arise about this concept: treat it as theoretical.
 Arch 2, bilaterally  lost (some say it becomes the stapedial artery, which is almost microscopic)
 Arch 3, bilaterally  along with the more superior portions of the anterior dorsal aortae of the head (above involuted carotid duct), become the internal carotid arteries;
    rest of arch 3 (base) and part of the upper aortic sac become the common carotid artery
 External carotid a is developed from independent of the branchial arches, but brs off of the 3rd arch near the base secondary artery
 Carotid duct (short part of dorsal aorta b/w where 3 rd & 4th arch connect to the dorsal aorta) = disappears (by involution around wk 7-9), leaving no trace of a
    connection b/w carotid arteries and subclavian artery or aorta
 Right arch 4  along with segment of the R dorsal aorta of the head (b/w 4 th arch and 7th intersegmental a) and the R 7th intersegmental a all become the right
    subclavian artery (note relation to R recurrent laryngeal n)
 A portion of the R middle aortic sac becomes the brachiocephalic artery
 A portion of the R dorsal aorta of the head distal to the 7 th intersegmental a: lost without any trace  Connection b/w R dorsal aorta of head and common dorsal aorta
    of body disappears  if persists then would get a aortic arch (ring) that surrounds the esophagus and trachea  would cause ripping of (aortic arch) during swallowing.
 Intersegmental aa arise b/w somites and go onto to become intercostal aa in thorax and other stuff in cervical region
 Left arch 4  in conjunction w/ a portion of the L middle aortic sac, L dorsal aorta of the head (distal to L 4 th arch), and common dorsal aorta (just below 12th
    intersegmental a) all contribute to the arch of the aorta. (note relationship to L recurrent laryngeal n).
 Left 7th intersegmental a  exclusively gives rise to the L subclavian artery and parts of the L axillary a.
 Arch 6, bilaterally  contributes to pulmonary arteries and (on left side only) ductus arteriousus (connection b/w L 6th arch & L dorsal aorta of head). The ductus
    arteriosus is an important structure in the fetus, which allows most of the blood pumped by the right ventricle to by-pass the lungs and instead enter the descending
    aorta  eventually closes and becomes the ligamentum arteriosum but if fails to close then would get a patent connection b/w pulm trunk and arch of aorta. On the
    right side only, the connection b/w the 6th arch and R dorsal aorta of the head disappears w/o leaving a trace.
 Coarctation of aorta = a narrowing of the aorta near ductus arteriosum  causes compromised blood flow and overload of blood vessels in brain (high BP) and low BP
    in lower extremities  ductus arteriosum can collect excess pressure due to coarctation
 L lower aortic sac forms the pulmonary trunk  pulmonary aa are actually secondary aa from 6th arch
    Major abdominal vessels aa arise from vitelline duct: Vitelline artery  initially supplies yolk sac. Its branches supply the developing gut and eventually become the
     celiac (anterior br), superior (middle brs), and inferior (lower brs) mesenteric arteries.
 Umbilical arteries  supply blood to the placenta via the umbilicus. The oxygenated blood then returns via the umbilical veins. Eventually around the umbilical
     arteries develop the internal and external iliac arteries. Persists to become the vessel that supplies the superior vesicle a
 Common dorsal aorta of body terminates into 2 brs  gives vitelline aa and common iliac a, which brs into internal iliac a  gives br to umbilical a (ant br)
 Adult pattern of major arteries: note how the pattern changes and what parts of the adult arteries come from these fetal arteries. Also note the origins of the ligamentum
     arteriosum and the ligamentum venosum.
Venous system development:
 The major veins of the embryo arise from 3 major venous systems: 1. vitelline system (first, paired), umbilical system (paired), cardinal system
 Sinus venosum & sinal horns = all blood returning from the heart passes first thru a left or right sinal horn, which joins a common sinus venousus before emptying into
     the atrium. A series of venous antioblastic plexuses develop early on, which quickly develops connections to all major veins. L sinus venosum dev into coronary sinus.
 Vitelline veins = drain the yolk sac to embryonic heart, where the first blood cells begin formation around the 4 th week
 Umbilical veins = drain the placenta to embryonic heart, supplying oxygenated blood to the fetus. There are 2 umbilical vv, but pretty soon the right one disappears,
     only the left umbilical v remains to drain the placenta.
 Cardinal system of veins = these are the vv of the embryo proper, draining all parts of the embryo (body) to the sinus venosus. These vessels include:
          o Anterior cardinal veins = these drain the head and what will eventually become parts of the chest;
          o Posterior cardinal veins = these drain the posterior body, including the abdomen, pelvis, and lower limb. Becomes extensively modified to form supracardinal
               and subcardinal vv, as the original posterior cardinal vv slowly disappears
          o Common cardinal vv = the anterior and posterior cardinal vv join together to become common cardinal vv, before they empty into the sinal horn.
Shift of systemic venous circulation to the right:
 Reduction of the left sinal horn to form coronary sinus
 There is a shift of the opening of the sinus venosus to the right side of the common atrium, just before the interatrial septum begins to develop. The wall of the sinus
     venosus is smooth, creating a sinus venarium, which has a smooth wall, as opposed to the original atrium wall, which has pectinate mm in it. (Similarly, in the left
     atrium, the incorporation of pulmonary vv creates a smooth-walled region).
 Coordination w. the atrial septation and formation of the septum primum.
Development of major vv (brief synopsis)
 Anterior cardinal vv form predominantly the subclavian, internal jugular, and brachiocephalic vv. Superior vena cava from R common and anterior cardinal; L
     brachiocephalic v anastomoses thru developing mediastinum to R brachiocephalic to join SVC (left anterior cardinal takes an oblique anastomoses w/ the common
     cardinal to create the L brachiocephalic v). Also note that remnants of the L anterior cardinal v will give rise to ligamentous remnant called the ligament of the L SVC.
 Note that R posterior cardinal v gives rise to azygos system. IVC forms from a mixture of vitelline v (hepatic segment), caval anstomoses (caval segment goes
     directly thru liver; connects it to cardinal system), subcaridnal v (subcardinal segment), renal anastomoses (connects it b/w R & L vv), and supracardinal v
     (supracardinal segment). R vitelline v pierces diaphragm to form terminal (hepatic) segment of the IVC. IVC then anastomoses to cardinal vv (dumps into sinus
     venosus). Critical element is caval anastomosis  other venous developments vary widely, and there is widespread disagreement.
 Note the hepatic portal v arises from the R & L vitelline vv, and the L umbilical v anastomoses w/ hepatic portal v to form a resultant v, ductus venosus (carries oxy
     blood), that will empty directly into the IVC and which will leave ligamentous remnants that will be discussed further w/ the liver.
 R umbilical v disappears; only L umbilical v is retained goes thru connecting stalk & L umbilical approaches liver.
 Double SVC = have a connection b/w brachiocephalic v and coronary sinus  only in some individuals
 No caval segment = blood from lower extremities drains up ascending lumbar to azygos v to IVC (sup part) b/c IVC can’t directly drain it
Circulation of blood in the embryo and fetus
 The most highly oxygenated blood enters via the umbilical v, which passes thru the ductus venosus before it is mixed w/ the blood in the IVC. Already, the oxygenated
     blood is compromised.
 About half of the blood from the IVC passes thru the foramen ovale and foramen secundum to the left atrium. This accomplished by the placement of the IVC (pointed
     medially) and pressure relationships in the L & R atria. This is pumped via the aorta to the head and upper limbs.
 Blood from the superior vena cava mixes w/ the rest of the blood from the IVC to be pumped directly into R ventricle and from there to the lungs. B/c the lungs are too
     small to receive all this blood, most of it is shunted away to the descending aorta via the ductus arteriosus. This is also the blood which finally goes to the placenta via
     the umbilical arteries; note that, when going to the placenta, the blood supply still has more oxygen than a typical systemic v.
INTERIOR HEART                                                   Function                                               Nerve supply   Blood supply
Right atrium  structures = SVC & osteum, crista                 Receives venous blood from the SVC & IVC; right                       R coronary
terminalis, lumbus fossa ovalis & fossa ovalis, R AV valve       auricle (primordial atrium) inc’s capacity of atrium
(tricuspid), coronary sinus & valvule (valve-like embryonic      as it overlaps the ascending aorta
remnant), IVC & osteum, R auricle
Osteum for SVC & IVC                                             Opening of vv into R atrium
Coronary sinus  derived from venous sinus
Valvule 
Fossa ovalis  depression left by R foramen ovale;
Limbus fossa ovalis = thickened edge around fossa ovalis
Crista terminalis  a ridge that stretches b/w osteums of        Marks boundary b/w R atrium and R auricle
SVC & IVC; terminal crest                                        internally
Pectinate mm – rough muscular ant wall of atrium; in L & R
Tricuspid valve  R AV valve; has 3 cusps (A, P, S);             Parachute model: blood coming from atria above
parachute; located posterior to the body of the sternum at       pushes the leaflets open & pressure w/in ventricle,
the level of 4th and 5th intercostal spaces; orifice = opening   when highest forces valves closed like a parachute;
thru which blood travels from atria to ventricles                thru which R atrium discharges deoxy blood to R
Right ventricle  structures = tricuspid valve leaflet,          Receives deoxy blood from R atrium                                    R marginal, Posterior
chordae tendineae, ant papillary m, septomarginal trabecula,                                                                           IV, Anterior IV
trabeculae carne, pulmonary aa (2)
Chordae tendinae – loose when valves are open b/c                Connect large AV valve leaflets to papillary mm; act
papillary mm are relaxed; in R & L ventricles                    as parachutes w/ AV valves; hold valves closed so
                                                                 blood doesn’t flow back & to prevent valves from
Papillary mm – attached to ventricular wall and chordae          Tighten cordae tendineae during contraction of
tendineae; in R & L ventricles                                   ventricles; prevents blood from pass back into atria
Septomarginal trabecula – moderator band; muscular bundle        Part of conducting system that carries impulses to
thaqt runs from inf part of interventricular septum to base of   papillary mm; terminal distribution of impulse;
ant papillary m.                                                 caries part of R bundle br of AV bundle
Trabeculae carne – irregular, interlacing network of mm on
ventricular wall; in L & R ventricles
Pulmonary valve – opens to pulmonary trunk at apex of            Sinus catches blood; blood moving up pushes valves
conus arteriosus; has 3 sinuses (L, R, A); attached margin is    open; blood moving against valves catches in sinus,
arched & free margin is straight; shape is in half moon & is     forces leaflets closed; thru which R ventricle
held down on sides by attached margin (attached to vessel        discharges deoxy blood to pulm aa
wall); no papillary mm or chordae tendineae
Left atriumstructure: L auricle (smaller than R auricle),       Forms base of heart; receives oxy blood from pulm                     L coronary, SA nodal,
Pulmonary vv (4), valvule of fossa ovalis, L AV valve            vv                                                                    circumflex
Valvule of fossa ovalis – remnant of L foramen ovalis
Mitral valve  L AV valve; called bicuspid valve but has 2       Parachute model: blood coming from atria above
sm and 2 lg (A & P) cusps; orifice = opening b/w atria and       pushes the leaflets open & pressure w/in ventricle,
ventricles for blood flow                                        when highest forces valves closed like a parachute;
                                                                 thru which L atrium discharges oxy blood to L
Left ventricle  strucures: mitral valve leaflet, chordae                                                                                           Posterior IV, L
tendineae, papillary mm; wall very thick compared to R                                                                                              coronary, Anterior IV,
ventricle b/c of higher pressure it has to produce to pump                                                                                          Circumflex, L marginal
blood to rest of body
Aortic valve – located behind mitral valve; has 3 sinsuses     Sinus catches blood; blood moving up pushes valves
(L, R, P); attached margin is arched & free margin is          open; blood moving against valves catches in sinus,
straight; shape is in half moon & is held down on sides by     forces leaflets closed; thru which L ventricle
attached margin (attached to vessel wall); no papillary mm     discharges oxy blood to aorta
or chordae tendineae
Cardiac skeleton – heart skeleton is made of fibrocartilage;   Attachment of valves, attachment of cardiac mm;
trigone = fibrocartilage that connects aortic and both AV      electrically isolates atria from ventricles -- perforated
valves (pulm valve is isolated)                                by AV node  atria and ventricles connected by a
                                                               small node to pass electric signals b/c fibrocartilage
                                                               doesn’t do so
Valve rings  Attached: mitral, tricuspid, aortic; separate
from rest: pulmonary
SA node  modified cardiac cells loc in cristae terminalis     The pacemaker (SA node) of the heart is one that            Vagal cardiac plexus &   R coronary or L
adjac to SVC; supplied equally by symp and parasymp            sets the pace  carry conductions to heart mm               symp innervation (T1-    coronary  SA nodal
                                                               (atria) to AV node                                          5)
AV node  loc in trigone fibrocartilage of R atrium;           Bypasses trigone fibrocartilage to transmit signal          Vagal cardiac plexus &   R coronary  AV nodal
supplied mostly by para and some by symp                       from atrial cardiac mm to ventricles (distributed to        symp innervation (T1-
                                                               AV bundle)  not fast conduction so slows down              5)
                                                               contraction to allow atrium to get all blood out it
                                                               needs to into ventricles before ventricular contraction
Atrioventricular Bundle (of His) m passes from AV node,       The only bridge b/w atrial and ventricular mm cells                                  Ant IV a
thru fibrocartilage, along membranous IV septum; divides
into L & R bundles at jxn b/w membranous and muscular
IV septum
L & R bundle brs  become Perkinje fibers                      Carry electrical impulse to either side of the IV                                    Ant IV a
                                                               septum to the Purkinje fibers
Perkinje fibers (R & L; cardiac conductive cells)  makes      Carry impulse to respective ventricles, IV septum,                                    Ant IV a
up rest of conducting system and most of membranous            and papillary mm
septum; continuation of L & R bundle brs
Interventricular septum – membranous (superoposterior            Partition b/w R & L ventricles, forming part of the
part, continuous w/ fibrocartilage) and muscular part            walls of each
 Importance of cardiac skeleton in valve fxn and in relation to cardiac contractions = Helps support heart mm & valves and helps electrically isolate atria from ventricles
      atria and ventricles connected by a small node to pass electric signals b/c fibrocartilage doesn’t do so
 Conductive system of heart and how it fxns to produce contractions = cardiac mm is capable of generating its own contractions (via SA & AV nodes);cardiac mm
     conducts that contraction from mm to mm until the whole heart is involve; cardiac conducting cells are specialized mm cells that carry conductions to the heart mm
     faster than normal cardiac mm cells; after depol, the cardiac m and conducting cell reset and go thru whole process of self-depol from scratch (they may never in self-
     depol if they are constantly depolarized from an outside source); the pacemaker (SA node) of the heart is one that sets the pace (they depol faster than the other cells)
      autonomic NS influence rate of heart fxn but does not control it
 MOORE: SA node initiates an impulse that is rapidly conducted to cardiac mm fibers in the atria, causing them to contract  impulse spreads by myogenic conduction
     that rapidly transmits the impulse from the SA node to the AV node  the signal is distributed from the AV node thru the AV bundle and its brs (R & L bundle brs),
     which pass on each side of the IV septum to supply subendocardial brs (Purkinje fibers) to the papillary mm and ventricular walls.
 Conductive pathway: SA node in R atrium  conduction thru atrial mm  AV node  atrioventricular bundle of His  L & R bundle branch
   Fxn of valves and when they open and close = AV valve fxn: parachute model, closes when pressure highest in ventricle; Semilunar valve fxn: sinuses (pockets) close
    valve when arterial pressure exceeds ventricular pressure
   Sequence of pumping blood: systemic venous blood to R atrium to R ventricle to pulmonary trunk to lungs; pulmonary venous blood from lungs to L atrium to L
    ventricle to acending aorta
   Aorta contains coronary arteries  R coronary above R sinus of aortic valve and L coronary above L sinus
   Cardiac mm: individual cells attached end-to-end w/ junctions that include a gap jxn (allow ions to travel from one cell to another)  jxn allow activation of one cell to
    activate the rest of the cells; mm forming groups in paths that can be traced into linear groups; attach to fibrocartilage of cardiac skeleton; superficial layer twists
    around at apex to improve flow (along w/ deep layer  twist ventricles to get all blood out; at rest, the heart is not pumping to full efficiency but twist mm to when
    heart needs full efficiency to pump blood) ; deep layer under cardiac skeleton; middle layers circle ventricles; ventricle and atrial mm attach separately, do not
    interconnect; atria and ventricles are connected only by the conducting system  stimulation of atria will stimulate ventricles
   Sinus venarum = smooth wall portion of post wall of R atriumderivative of venous sinus
   Conus arteriousus (infundibulum) superiorly tapered cone part of right ventricle that leads into pulmonary trunk

 Superficial structures: skin – thicker dorsally, thinner ventrally, loosely attached to the underlying tissue everywhere except at the umbilicus; subcutaneous tissue –
   mostly fat, primary adipose tissue
 Layers of abdominal wall: skin (epidermis and dermis), superficial fascia = hypodermis (fatty layer – Camper’s, membranous layer – Scarpa’s), deep (muscular) fascia,
   muscles of abdominal wall, transversalis fascia (lines most of abdominal cavity, much thicker than deep fascia), extraperitoneal CT(mostly fat and CT), parietal
   peritoneum (lined by serous membrane much like that around heart and lungs)
 Scarpa’s fascia – continuous w/ & attaches to fascia lata and tunica dartos scroti
 Linea alba – white line aponeurosis along midline of abdomen
 Linea semilunaris – projection lateral to linea alba that runs from pubic crest to costal margin
 Umbilicus = where all layers of abdominal wall fuse
 Boundaries of abdomen = 1. Diaphragm above & plane of pelvic inlet below; 2. Bony boundaries: xiphisternum, costal margin (7 th-10th costal cartilages and ribs),
   pelvic bones  iliac crest (upper region of hip; at level of L4), anterior superior iliac spine, iliac tubercle, posterior superior iliac spine, 2 coxal bones fused at middle at
   the pubic symphysis, pubic crest (extending laterally from the pubic symphysis ending as the pubic tubercle); 3. Inguinal ligament (b/w pubic tubercle and ASIS 
   bony landmarks only at extreme superior and inferior ends
 Surface of abdomen is less extensive than interior, as interior extends upward under diaphragm and inf’ly into false pelvis
 Abdomen divided into 4 quadrants: Upper R, Upper L, Lower R, Lower L by midsagittal (going vertically) and transumbilicus (going horizontally) lines going thru
   umbilicus at L3-4 IV disc
 Abdomen divided into 9 regions (by 2 pairs of planes): 2 vertical planes connecting the midclavicular lines w/ the midinguinal lines; 2 horizontal planes  transpyloric
   plane (lies midway b/w suprasternal notch and pubic symphysis at level of lower border of L1; crosses the pyloric region of the stomach, the 1st part of duodenum, the
   pancreas, and the fundus of the gallbladder. The hilum of the R kidney lies just below it, and the hilum of the L kidney lies just above it) and intertubercular plane (lies
   at level of tubercle of the iliac crest, cuts thru L5)
 Regions: Superior = R & L hypochondriac regions on either side of the epigastric region; Middle = R & L lateral (lumbar) regions on either side of umbilical region;
   Inferior = R & L iliac (inguinal) regions on either side of hypogastric region
 Contents of each region:
        o R hypochondrium = liver
        o Left hypochondrium = fundus of stomach, upper part of spleen
        o Epigastrium = liver, stomach, pancreas
        o R lumbar = ascending colon and lower part of R kidney
        o L lumbar = descending colon, lower part of L kidney
        o Umbilical region = coils of small intestine and transverse colon
        o R iliac = cecum and appendix
        o L iliac = descending and sigmoid colons
        o Hypogastrium = coils of small intestine, full bladder, and pregnant uterus
   Fluid in abdomen can pass over pubic crest to reach scrotum or labium majus
   Spinal nn run b/w internal abdominal oblique and transverses abdominis mm give lateral and anterior cutaneous brs
   Dermatomes: ant cutaneous br of 7th intercostal n innervates region below xiphoid process; ant cutan br of 10 intercostal n innervates region of umbilicus; ant cutan br
    of 12 intercostal and 1st lumbar nn innervate suprapubic regions (L1 spinal nn divides into iliohypogastric and ilioinguinal nm)
   Abdominal wall supplied by 10th-11th intercostal, subcostal, and 1st 4 lumbar segmental aa via ant and lateral brs; internal thoracic a brs = musculophrenic (supplies
    twigs along costal margin) & superior epigastric a

Rectus abdominis m          Ligament of Pubic            Xiphoid process and        Flex trunk                          Thoracoabdominal nn;       Superior epigastric a,
ant-lat m of abdominal       symphysis and sup            costal cartilages 5-7                                          iliohypogastric n          inferior epigastric a
wall; vertical fibers; loc   ramus of pubic bone
on either side of linea
alba; thick inf’ly and
thin sup’ly; has
tendinous intersections
on ant surface but don’t
extend thru depth of m;
3 tendinous
intersections are
adhered to ant layer of
rectus sheath; lateral
borders are convex and
correspond to linea
External abdominal           External surface of ribs     EAO aponeurosis (to        Flex trunk and pelvis, bend side-   Thoracoabdominal nn;       Sup epigastric a, inf
oblique m  sup-lat to       5-12 (upper 5 origins        linea alba & pubic         to-side, rotate trunk, and bear     iliohypogastric n;         epigastric a, deep
inf-med fibers; most         interdigitate w/ serratus    tubercle); lower 2         down; post margin forms             subcostal n (lowest slip   circumflex iliac a
superficial of flat          anterior & lower 3 w/        origins descend            lumbar triangle w/ lat margin of    of EAO m)
abdominal mm                 costal insertions of lats    vertically to insert on    lats dorsi and iliac crest
                             dorsi)                       outer lip of iliac crest
Internal abdominal           Post layer of                IAO apoeneurosis at        Flex trunk and pelvis, bend side-   Thoracoabdominal nn;       Sup epigastric a, inf
oblique m inf-lat to        thoracolumbar fascia,        linea semilunares to       to-side, rotate trunk, and bear     iliohypogastric n          epigastric a, deep
sup-med fibers; 2nd          ant 2.3 of iliac crest,      linea alba & pubis; post   down                                                           circumflex iliac a
layer; splits into an ant    later 2/3 of inguinal lig,   fibers ascend vertically
layer (in upper ¾ of         aponeurotic iliacus          to insert on inf borders
abdomen) that passes         fascia (deeper)              of ribs 10-12 and costal
ant to rectus abdominis                                   cartilages
mm & a post layer that
passes post to the mm
 2 layers unite at
linea alba; in lower ¼
of abdomen the IAO
does not separate and
passes ant to rectus
abdominis m; lower
fibers course inf and
med arching over
spermatic cord to insert
on pubis
Transverses abdominis        Deep surfaces of ribs 7-    Transverses abdominis     Flex trunk and pelvis, bend side-   Thoracoabdominal nn;   Sup epigastric a, inf
m  transverse fibers;       12 and costal cartilages,   aponeurosis               to-side, rotate trunk, and bear     iliohypogastric n      epigastric a, deep
3rd layer; widest at level   thoracolumbar fascia,                                 down                                                       circumflex iliac a
of iliac crest and           ant ¾ of iliac crest,
narrower sup’ly &            lateral 1/3 of inguinal
inf’ly; combines w/          lig, iliacus fascia
post layer of IAO
aponeurosis in upper ¾
of abdomen to form
post layer of rectus
sheath; in inf ¼ of
abdomen all 3
aponeurotic layers pass
ant to rectus abdominis
m and only
transversalis fascia
passes post to the mm;
deeply invested by
transversalis fascia
Pyramidalis m               Pubis                       Linea alba                Pulls down on linea alba            Thoracoabdominal nn;   Sup epigastric a, inf
vertical fibers; ant-lat m                                                                                             iliohypogastric n      epigastric a, deep
of abdominal wall;                                                                                                                            circumflex iliac a
insignificant and often
lacking; loc w/in rectus
sheath, overlapping inf
attachment of rectus
abdominis m
Rectus sheath               Upper ¾ of abdomen:         Lower ¼ of abdomen:
contains rectus              ant layer = EAO & ant       ant layer = EAO, IAO,
abdominis &                  layer of IAO                & transverses abdominis
pyramidalis mm, the          aponeuroses; post layer     aponeuroses; post layer
sup & inf epigastric vv;     = post layer of IAO &       = transversalis fascia
arcurate line = line of      transverses abdominis
shift in aponeurotic         aponeuroses and
investment of post layer     transversalis fascia;
of rectus sheath in
lower ¼ abd wall
Inguinal ligament –          ASIS                        Pubic tubercle            Gives origin to fibers of IAO
thickened rolled under                                                             and transversus abdominis m
inf free margin of EAO
Lacunar ligament –                                                                 Spermatic cord lies on lacunar
flattened medial portion                                                           lig as it emerges from
of inguinal lig inserting                                                          superficial inguinal ring
on pectin of pubis
Superficial inguinal       Lateral crus: inf border    Intercrural fibers =      Spermatic cord (round lig)
ring – triangular gap w/ of ring                       Form sup-lat margin of    passes thru the ring; exit from
inf-med opening            Medial crus: sup-med        ring and extend to        inguinal canal
created from split in      border                      merge w/ EAO
EAO aponeurosis (cleft                                 aponeurosis covering
represents weakening                                   the cleft
in EAO aponeurosis)
Quadratus lumborum
 EAO, IAO, and transverses abdominis mm form 3 layers; fiber arrangement gives strength to abdominal wall; 3 mm insert as aponeuroses that combine to form rectus
     sheath of rectus abdominis
 External spermatic fascia = Delicate sheath investing the spermatic cord and testis
 Conjoint tendon (Falx Inguinalis) – formed by fusion of IAO and transverses abdominis aponeuroses; anchored laterally to pectin pubis
 Neurovascular plane = an interval b/w the IAO m and transverses abdominis m  help define separation b/w these 2 mm layers in locations where their fibers are
     tightly apposed; segmental nn and aa pass thru this plane
 Transversalis fascia – deep fascia of transverses abdominis mm; lined internally by, and intimately apposed to, the abdominal parietal peritoneum; Invest entire
     abdominopelvic cavity, ascending to form the inf fascia of diaphragm and descending to form the superior fascia of pelvic diaphragm
 Collective fxn of abdominal mm = rotation of abdomen and trunk; hold in and protect abdominal viscera; inc intra-abdominal pressure

Inguinal canal  4 cm        Formed as the inf fold      Medially attaches to the   Flattens medially w/ some fibers
long oblique passage         of the EAO aponeurosis      pubic tubercle             attaching to the pectin of the
lying parallel to the                                                               pubis, forming the lacunar lig,
inguinal lig; contents =                                                            upon which lies the spermatic
spermatic cord/round                                                                cord as it exits the superficial
lig, ilioinguinal n,                                                                inguinal ring
genital br of
genitofemoral n,
cremasteric a
Deep inguinal ring =         Loc at mindinguinal                                    Opening into inguinal canal;
finger-like diverticulum     point (pt on inguinal lig                              primary content is spermatic
of transversalis fascia      midway b/w ASIS and                                    cord (males) or round lig
(not a ring); opens lat to   pubic symphysis) ½                                     (females)
the inf epigastric a,        inch above inguinal lig
below the inf margin of
the transverses
abdominis m
Superficial inguinal         Inf border of ring          Sup border formed by       Spermatic cord passes thru the
ring = triangular defect     formed by lateral crus of   medial crus; lat margin    ring
in EAO aponeurosis           EAO apon (inf margin        formed by intercrural
                             of inguinal lig)            fibers and extend to
                                                         merg w/ EAO apon
Spermatic cord =             Deep inguinal ring lat to   Exits superficial          Suspends testis in the scrotum
ductus deferens,             inf epigastric a, passes    inguinal ring, ends a      and contains structures running
deferential a & v,           thru inguinal canal         scrotum at post border     to and from the testis; carries
testicular a,                                            of testis                  sperm from testis into pelvis, to
Pampiniform Venous                                                                  end at prostatic urethra;
plexus, lymphatics,
autonomic nn of testis,
investment layers of
spermatic cord (internal
spermatic fascia,
cremasteric m & fascia,
external spermatic
Internal spermatic         Transversalis fascia
Cremasteric m & fascia     Mm: formed from                                        Mm: contracts to draw the testis                                 Cremasteric a
 fascia is derived        lowermost fascicles                                    superiorly in the scrotum,
from that of superficial   IAO m arising from                                     particularly when it is cold  in
and deep surfaces of       inguinal lig                                           attempt to regulate temp of
IAO m                      Fascia: IAO apon                                       testis for spermatogenesis
Round ligament – main
occupant of inguinal
canal in females
Scrotum  comprised        A pouch formed by                                                                          Ant scrotal nn (genital br
of skin and tunica         bilateral contributions                                                                    of genitofemoral n,
dartos scroti              joined at a midline                                                                        ilioinguinal n), post
                           raphe that is continuous                                                                   scrotal nn (pudendal n)
                           from ventral surface
                           ofhte penis to the anus
Tunica dartos scroti = a
thin subcutaneous
muscular layer
Testis  found outside                                                                                                Testicular plexus (vagal     Testicular a
the abdomen in a                                                                                                      parasymp fibers on
scrotal sac                                                                                                           testicular a & T7 symp
Ductus deferens –                                                                                                                                   Deferential a & v
muscular tube that
convesy sperm from
epididymis to
ejaculatory duct
 Boundaries of inguinal canal = deep inguinal ring, superficial inguinal ring, floor of the canal, ant wall, post wall, roof (open)
 Floor of the canal formed by the medial half of the inguinal lig and the lacunar lig
 Anterior wall = formed entirely by the EAO apon reinforced laterally by the IAO mm; inf fibers of IAO m take origin from the lateral part of the inguinal lig and
    contributed to the ant wall; medial to the deep inguinal ring, the IAO splits to allow passage of the spermatic cord – the thin aponeurotic medial continuation of this mm
    now contributes to the post wall of the canal; the apon of the IAO and tranversus abdominis fuse medially to form the conjoint tendon
 Posterior wall = complex layout formed by the transversalis fascia and the conjoint tendon
 Roof is actually open, continuous w/ the plane b/w the EAO, IAO, and transverses abdominis m
 In the female, the inguinal canal is smaller, containing only the round ligament, round ligament a & v, the ilioinguinal n, and genital br of genitofemoral n; difficult to
    differentiate the layers
Descent of the testis:
 Testis dev in the intraperitoneal connective tissue of the upper lumbar region and remains in the abdominal cavity thru mot of the intrauterine life. Testis dev in
    abdomen in assoc w/ early kidney (mesonephric) and its duct  mesonephric duct becomes ductus deferens
   Begins as a bulge into the peritoneal cavity suspended by a lig formed partly of peritoneal membrane. The lig condenses further to form the Gubernaculum Testis (a
    fibrous cord) which attaches the dev (primordial) testis to the abdominal wall in the region of the scrotal swelling (site of the future deep ring of the inguinal canal.
    Gubernaculums swells with water in late fetal life; this opens up a space in the inguinal canal, which allows testis to pass (tunica vaginalis)
 The Processus Vaginalis is an evagination of the peritoneal cavity into the scrotal swelling, penetrating the mm and fascial layers of the abdomen. Gubernaculum
    shrinks (becomes a small unnoticeable lig) and testis pass thru processus vaginalis.
 By the 5th month, the testis has migrated near the inguinal ring; begins pushing into the inguinal ring by 7 th month; usually lies in the scrotum by 8th month.
 Passage of the Processus Vaginalis into the scrotal pouch attenuates (thins) the muscular abdominal wall and draws out the derivatives of the muscular layers into the
    scrotum, where the adult structures are observed: 1. External spermatic fascia, derived from the EAO m; 2. Cremaster m and fascia, derived from IAO m 3. Internal
    spermatic fascia, derived from the transversalis fascia; note that the transverses abdominius m has no contribution to the coverings of the spermatic cord or the contents
    of the scrotum.
 Also, the neck of the Processus Vaginalis constricts and is usually sealed off, leaving only a dimple in the peritoneaum at the location of the deep inguinal ring where
    the testis passed.
 Thus, the remnant of the Processus Vagninalis is a sealed off serous sac, called the tunica vaginalis testis, that partially encloses the testis on its ant and lat aspects. On
    rare occasions, the processus vaginalis persists, thus providing a permenant link b/w the abdominopelvic and 2 scrotal cavities. This could lead to congenital cause of
    herniations of viscera into the scrotum. Tunica vaginalis testis is a serous sac w/ a visceral layer apposed to the testis, the epididymis, and lower part of the spermatic
    cord and a more extensive parietal layer, which extends partially up the spermatic cord.
 Irregularities in closure of the processus vaginalis can lead to some types of hernia and hydrocele. Failure of descent of the testis is called cryptorchidism, and
    migration to an improper location, such as into the thigh or perineum, is called ectopic testis.
Inguinal Hernias
 The point thru which the testis passes in its descent represents a weakness in the abdominal wall and predisposition to herniation of the abdominal contents.
 Congenital hernia = results from incomplete closure of the neck of the processus vaginalis and extrustion of the abdominal contents into the spermatic cord
 Acquired hernias = appear b/c of abdominal wall weakness
 Indirect inguinal hernia = protrusion of abdominal contents lateral to the inf epigastric vv; begins at the deep inguinal ring; structures pass thru the deep inguinal ring,
    into the spermatic cord in the inguinal canal, exiting thru the superficial inguinal ring and into the scrotum; follows the path taken during the descent of the testis.
    Indirect hernias can be congenital or acquired. With congenital indirect hernia, abdominal contents enter the tunica vaginalis testis thru the spermatic cord. Acquired
    indirect hernias usually do not expel contents all the way into the tunica vaginalis.
 Direct inguinal hernia = protrusion of abdominal contents medial to the inf epigastric vv; does not begin at the deep inguinal rig, rather, the abdominal contents push
    directly thru the weakened wall at the superficial inguinal ring and rarely continues into the scrotum. Virtually all direct hernias are acquired. The inguinal region of the
    female is firmer that that of a male, making it less prone to direct or indirect herniation.
 Structure of testis: found in scrotal sac; the two scrotal sacs are separate, divided by a midline septum; they are surrounded by membranes: skin, tunica dartos scroti,
    spermatic and cremasteric fascia, and tunica vaginalis testis; sperm manufactured in seminiferous tubules; pass into rete testis and from there into ductuli efferentes
    (efferent ducts); from there to the epididymis, where the sperm are stored and maturation begins. Epididymis narrows into a ductus deferens, which continues up thru
    the inguinal canal into the pelvic region.
 Lymphatic vessels draining the testis and closely associated structures pass to the lumbar lymph nodes
 Intraperitoneal: peritonealized organs having a mesentery = stomach, small intestine (jejunum and ileum), transverse colon, liver and gallbladder.
 Retroperitoneal: organs without a mesentery and associated with posterior body wall = aorta, inferior vena cava, kidneys and suprarenal glands.
 Secondarily retroperitoneal: organs which had a mesentery once and lost it during development,= pancreas, duodenum, ascending and descending colons.

 Peritoneum = 2-layered serous membrane providing a lubricated plane for mobility of abdominal viscera --> parietal peritoneum = lines the abdominal wall; visceral
   peritoneum = invests the abdominal viscera
 As the abdominal viscera developed, they push into the abdominal cavity --> some organs protruded into the cavity only partially and are invested only on their ant
   surface (retroperitoneal organs e.g kidneys, ascending colon); some organs penetrated deeply into the abdominal cavity and are completely enclosed in visceral
   peritoneum (intraperitoneal organs e.g. stomach, most of small intestine)
 Intraperitoneal organs are enclosed and attached to the posterior abdominal wall by a double layer of peritoneum called a mesentery (holds viscera onto body wall)
   Mesogastrium is the mesentery of the stomach; transverse mesocolon is the mesentery of the transverse colon; organs w/ a mesentery are motile.
   The peritoneal cavity is divided into 2 sacs: greater peritoneal sac (an incision thru the abdominal wall pentetrates the greater sac) and lesser sac (omental bursa; lies
    post to the stomach, liver, and lesser omentum; contained by mesenteries of the developing stomach)
   Omental bursa is situated over, and provides access to: celiac a, pancreas, duodenum, bile duct; often, surgeons need to access this space for things like pancreatitis,
    duodenal ulcers, removal of gallstones from bile ducts; created by expansion of dorsal & ventral mesogasters;
   Omentum = a folded sheet of peritoneum --> lesser and greater omentum
   Lesser omentum connects the lesser curvature of the stomach and the 1st part of the duodenum w/ the liver; comprised of hepatogastric and hepatoduodenal portions;
    lies post to the left lobe of the liver and attaches to the liver in the fissure of the ligamentum venosum, where it attaches to the porta hepatis.
   Greater omentum = a folded, fat-filled double layer of peritoneum depending from the greater curvature of the stomach, connecting the stomach w/ the diaphragm,
    transverse colon, and spleen; comprised of 4 layers of peritoneum which are usually fused, thereby obliterating the inf part of the omental bursa
   Omental (epiploic) foramen = opening thru which the omental bursa (lesser sac) communicates w/ the greater sac; is opening behind the R free margin of the lesser
    omentum; opens into the sup part of the lesser sac; the inf portion is usually obliterated in the adult by the fusion of the 2 layers of the greater omentum
   Peritoneal ligaments = double layered peritoneum connecting one organ w/ another (also comprise parts of the omenta); may contain blood vessels or remnants of fetal
    vessels (e.g. falciform ligament, containing the ligamentum teres which is the obliterated umbilical v); e.g. hepatogastric and hepatoduodenal ligs (of the lesser
    omentum) and the gastrocolic, gastrophrenic, and gastrosplenic (gastrolienal) ligs (of the greater omentum)
   Peritoneal recesses = where the visceral peritoneum departs from one organ and passes to another organ creates a space called a recess; e.g. hepatorenal recess – space
    b/w the right lobe of the liver and the right kidney; important to consider when fluid (including blood or pus) pools in the abdominal cavity
   Paracolic gutters = channels related to the ascending and descending colons; both have medial and lateral paracolic gutters; the right lateral paracolic gutter is
    associated w/ the ascending colon – important b/c it is continuous above w/ the right hepatorenal recess and below w/ certain pelvic receses; since the paracolic gutters
    slope sup’ly, fluid in the abdominal cavity of a supine patient will tend to ascend into the sup abdomen.
   Development of GI tract = gut develops out of endoderm. As the head pulls forward, it pulls the gut ant’ly. The developing gut becomes divided into 3 segments: 1.
    Rostral to vitelline duct is the forgut (e.g. pharynx, esophagus, stomach, duodenum); 2. Adjacent to the vitelline duct is the midgut (e.g. small intestine proper, ant large
    intestine); 3. Post to it is the hindgut (e.g. remaining large intestine, cloaca)
   Retroperitoneal = when a piece of intra-abdominal viscera fuses w/ the post body wall, its visceral peritoneum fuses w/ parietal peritoneum. The organ thus becomes
    secondarily retroperitoneal
   Esophageal & stomach development: Pharynx narrows caudal to the 4 th pharyngeal pouches to become the esophagus. The connective tissue and muscle layers are
    derived from mesodermal mesenchyme. The foregut then swells to become the stomach. Its curvatures are similar to the adult except they face ventral and dorsal. Gut
    rotation accounts fro the adult curvatures. As the gut rotates clockwise 90 degrees, the dorsal mesogastrium (mesentery) forms the pouchlike omental bursa. Both the
    tail of the pancreas and the spleen will be imbedded in this dorsal mesogastrium. The stomach will also retain a portion of the ventral mesentery, which encloses the
    liver. The specialized gastric cells differentiate early but are not functional until near term.
   Formation of Intestines: As the gut tube lengthens, near the midpoint a loop extends into the belly stack at the attachment to the yolk stalk. The gut tube just cephalic to
    the yolk stalk is the transition b/w small and large intestines. The gut tube just caudal to the yolk stalk will form the large intestine. There is a counterclockwise turn in
    this loop of gut tube. This twist results in the adult positioning of the ascending and transverse colons. The coiling of the small intestines is the result of rapid
    lengthening. As the portion of the colon that projects into the belly stalk is finally drawn into the peritoneal cavity, its cecal end swings to the right and downward.
   Development of the liver: The liver forms initially as a diverticulum from the floor of the foregut into the septum transversum. The mesenchyme of the septum
    transversum induces the endoderm of the hepatic outgrowth to begin to branch and anastomose forming a network of hepatic tubules. The intertubular space becomes
    invaded by a maze of sinusoids.
   Development of the pancreas: The pancreas develop from the same region of the gut tube as the liver and at about the same time. It is derived as a dorsal diverticulum
    from the duodenal endoderm and one that arises ventrally from the hepatic diverticulum. These 2 primordia fuse when the gut tube rotates. The ventral pancreatic bud
    is carried into the dorsal mesentery to fuse w/ the larger dorsal pancreas. The formation of the pancreas is the result of interaction b/w the endoderm and the
    surrounding mesenchyme. The mesenchyme is req for endodermal outgrowth and branching. The acini and ducts of the pancreas are endodermally derived w/ the Islets
    of Langerhas forming by budding off the developing acini. Dorsal duct anastomoses w/ the ventral duct.
   Body cavities & Mesenteries: The body cavities include the pericardial cavity, the pleural cavities, and the peritoneal cavity. All three are derived from the coelom of
    the embryo. Coelom arises as the lateral plate mesoderm splits into the splanchnic and somatic mesoderm. The folding process of the embryo separates the extra-
    embryonic and intra-embryonic portions of the coelom. As this folding occurs, splanchnic mesoderm that is adjacent to the gut tube fuses to become the primary
    mesentery, consisting of both a ventral and dorsal component. The primary mesentery initially keeps the right and left coeloms separated until most of the ventral
    mesentery breaks down. This establishes the peritoneal cavity w/ the viscera attached to the body wall via the dorsal mesentery. The only major remnant of the ventral
    portion of the primary mesentery is the ventral ligament of the liver or the falciform ligament in which passes the umbilical vessels. Initial mid/hind gut has a single
    common dorsal mesentery. Vitelline duct still connects to the yolk sac (this would be 5 th wk). Vitelline a occupies center of mesentery.
   Musculoskeletal ligaments are dense regular CT that attaches bone to bone. Visceral ligaments are parts of mesentery that connect one organ to another.
   Early 4th week cross-section of middle of gut tube & yolk sac: ectoderm, somatopleure, dorsal common mesentery, intra-embryonic celom, splanchnopleure, endoderm,
    and vitelline duct.
   Late 4th week foregut cross section: dorsal mesentery, gut tube, ventral mesentery
   Late 4th week mid/hindgut cross section: dorsal common mesentery, gut tube, ant’ly have L & R peritoneal cavities fused into continuity
   End of 5th week: organs w/in forgut: dorsal mesogaster, spleen, stomach, ventral mesogaster, liver
   6th week foregut: rotation of stomach, have kidney, pancreas, dorsal mesogaster, spleen, liver, ventral mesogaster
   Weeks 8-9: final structures = kidney, fusion fascia, pancreas, splenorenal lig, spleen, gastrosplenic lig, stomach, lesser omentum, liver, falciform lig
   Organs derived from foregut = liver, spleen, gall bladder, bile duct, stomach, duodenum, transverse colon, ascending colon, descending colon
   Mesenteries derived from ventral mesogaster = lesser omentum, falciform lig, coronary ligs
   Mesenteries derived from dorsal mesogaster = gastrophrenic lig, gastrosplenic lig, gastrocolic lig, greater omentum, splenorenal lig
   Rotation of mid – and hind-gut: bent tube extending into umbilicus w/in its own pouch. It begins to rotate just before the fetal period, undergoing counterclockwise
    rotation. Gut rotates roughly 270 degrees, so cecum is on the right. It flips so that transverse colon lies ant to the duodenum; it pulls back into abdominal cavity around
    9th-10th weeks.
   Mid/hind gut mesenteries: cut ventral mesogaster, dorsal mesogaster, mesoduodenum, common dorsal mesentery, vitelline a, transverse colon and transverse
    Mesocolon, ascending colon retroperitoneal, cecum and appendix intraperioteal
   Midgut mesenteries: cut ventral mesogaster, greater omentum, duodenum – mesentery fused to body wall (retroperitoneal), free small intestine still intraperitoneal (w/
    mesentery proper)
   Hindgut mesenteries: descending colon retroperitoneal, sigmoid colon and sigmoid mesocolon, rectum
   Duodenal folds and fossae: duodenum has 4 parts; retroduodenal fossa; paraduodenal fossa; superior duodenal fold; superior duodenal fossa; inferior duodenal fold;
    inferior duodenal fossa --> significance = pocket where bacteria can hid in cases of peritonitis; if large enough, a piece of bowel can get caught in space and become
    constricted, therefore causing ischemia; fossae and oflds are more conspicuous in some indivs than others, sometimes almost seem absent.
   Iliocecal junction folds and fossae: vascular cecal fold, superior ileocecal recess, iliocecal fold, mesoappendix, inferior ileocecal recess
   Arteries of ileocolic junction: colic br, ant cecal a, ileal br, post cecal a, appendicular a, iliocolic a
   Significance of folds/ fossae: a place for ilieum or appendix to get lodged or twisted; a place for bacteria to lodge and hide; anatomical relationships are important for
    appendicitis surgery; bacteria also like hide in paracolic gutters and grooves of side of ascending and descending colons during peritonitis.

STOMACH,                  PANCREAS,                   DUODENUM,                   CELIAC A
Stomach – loc in L        Esophogastric jxn is loc                                Produce pepsin and HCl, which        Ant and post vagal trunks    L gastric a
upper quadrant of         at level of xiphoid                                     hel digest proteins and reduce       and their brs (parasymp);
abdomen; receives         process                                                 bacteria enzymes and fluid          T6-9 symp fibers via
esophagus 1-2 cm          Intraperitoneal                                         will double vol of contents from     greater splanchnic n to
below the hiatus of the                                                           that of food taken in; drops         the celiac and superior
diaphragm;                                                                        lower as it fills; it is primarily   mesenteric ganglia
gastrophrenic lig is                                                              fixed at the upper end
peritoneal reflection                                                             (esophagus) and lower end
from the diaphragm                                                                (duodenal), ergo position of
onto the stomach                                                                  stomach is not fixed.
Duodenum  struct:        Secondarily                                             Receives chyme from stomach;         Vagus n (parasymp); T5-      Celiac trunk, superior
sup part, inf part,       retroperitoneal                                         1st part has alkaline mucus to       9 symp fiber via greater     mesenteric a
accessory pancreatic                                                              protect it from acid damage;         splanchnic n to celiac
duct; bile duct,                                                                  pancreatic ducts emptying into       and superior mesenteric
descending part, main                                                             2nd part carry bicarbonate to        ganglia
pancreatic duct,                                                                  buffer acidic chyme to neutral;
suspensory ligament,                                                              digestion and absorption of
horiz. part, ascending                                                            carbs, lipids, and proteins
part; interior of
descending part (2nd
part) = minor papilla,
major papilla,
longitudinal fold, plica
Pancreas  gland w/        Secondarily                                            Exocrine secretions = pancreatic     T8-9 symp fibers via        Splenic a, sup mesenteric
exocrine and endocrine     retroperitoneal; lies                                  juice, involved w/ digestion of      thoracic splanchnic n;      a
fxn; 4 parts (head,        transversely extending                                 fats, proteins, and carbs;           vagus n (parasymp)
neck, body, tail); ducts   from duodenum to the                                   endocrine secretions = insulin,
= main, accessory;         spleen                                                 involved w/ sugar metab
unicate process                                                                   (secretred from cells of islets of
                                                                                  Langerhans); Produce digestive
                                                                                  enzymes (trypsin, amylase,
                                                                                  lipase) and buffer (bicarbonate),
                                                                                  which are emptied into
                                                                                  duodenum; produce insulin and
                                                                                  glucagons hormones which are
                                                                                  secreted directly into capillaries
                                                                                  in organ
Main pancreatic duct       Tail of pancreas               At the head, the duct
                           (receiving small ducts as      turns inf and post,
                           it passes L to R)              curving to join the
                                                          common bile duct to
                                                          empty on the summit of
                                                          the greater (major)
                                                          duodenal papilla
Accessory pancreatic                                      Empties onto lesser
duct                                                      (minor) duodenal papilla
                                                          which is usually sup to
                                                          the greater papilla
 Stomach: Cardia = region of stomach immediately surrounding the esophagus; Fundus = dome-like elevation above the cardia filling the dome of the diaphragm on the
     left; Body = desceding part of stomach; Angular notch = dent in the lesser curvatue demarcating the body to the left from the pylorus to the right; Pylorus = sharply
     narrowed portion consisting of the pyloric antrum adjacent to the angular notch, and the pylorus containing the pyloric sphincter, a muscular constriction separating the
     stomach from the duodenum; Greater curvature = lower left border; attaches to the greater omentum, to the transverse colon via the gastrocolic lig, and to the omental
     apron; Lesser curvature = upper right border; attaches to the lesser omentum and to the liver via the gastrohepatic lig
 Stomach is a bag-like sac; begins w/ esophagus: note stratified squamous epithelium of esophagus ends abruptly at the simple columnar mucous-secreting epithelium of
     the stomach at the zig-zag (Z) line; inner lining (mucosa) thrown into folds called rugae which can be stretched out as stomach fills.
 Stomach lymph nodes = pericardial, hepatic, pancreaticosplenic, L gastric, celiac, pyloric, R gastroomental nodes; direction of flow = stomach  pericardial  L
     gastric  celiac nodes; stomach  pancreaticosplenic  celiac nodes; stomach  R gastroomental  pyloric  celiac; stomach  hepatic  celiac
 Duodenum: counter-clockwise rotation of developing intestine puts a sharp turn in the duodenum, places the pancreas in the u-shaped curve, and places both behind the
     transverse colon when the gut is retracted into the abdomen; the transverse mesocolon assumes the place of the peritoneum over the duodenum and pancreas and the 2
     organs are thereafter situated retroperitoneal; the interior contains muscular circular folds and mucous membrane containing intestinal villi.
 Major papillae = where main pancreatic duct + common bile duct empty; Minor papillae = wehre accessor pancreatic duct empties.
   1st part (superior part) lies at the level of T11, in relation to quadrate lobe of liver and neck of the gall bladder; head of the pancreas lies below and behind, and the
    common bile duct passes behind along w/ the portal vein and the gastroduodenal a; 2 nd part (descending part) lies at the level of T12 (w/ continuations from T11-L1);
    contains major (greater) duodenal papilla posteriorly, which receives the common bile duct and the pancreatic duct, and sometimes contains a minor (lesser) duodenal
    papilla superior to the greater, which receives the accessory pancreatic duct; curvds around the head of the pancreas medially; in contact with the right lobe of the liver
    laterally; overlies the hilum of the right kidney, resting upon the renal vv and IVC; 3 rd part (inferior part) in relation to the sup mesenteric a above it and the inf
    mesenteric a below it. Overlies the IVC and right testicular (ovarian) a; 4th part (ascending part) is continuous w/ the duodenojejunal flexure or xn jejunoileum. Lies on
    the left side of the aorta across the left testicular (ovarian) a.
   Pancreas (4 parts): Head = retroperitoneal in the U formed by the duodenum, deep to the transverse colon and its mesocolon. Superior lies the pylorus and inf lie the
    coils of the small intestine. Overlies L2-3 as well as the IVC, renal vv and the R renal a, the aorta, and common bile duct; Neck = grooved on its post surface by the sup
    mesenteric a and v, which emerge from below the pancreas and above the 3 rd part of the duodenum to enter the mesentery. Also lies on the jxn of the sup mesenteric v
    and the splenic v as they form the portal v; Body = triangular in cross section. The ant surface lies on the floor of the omental bursa. The post surface crosses (from L to
    R) aorta, left suprarenal gland, left kidney, splenic v. inf surface lies on the transverse mesocolon and the duodenojejunal flexure; Tail = directed up and backward,
    frequently making contact w/ the spleen and splenic flexure of the colon.
   Veins of pancreas: venous system parallels arterial system; drainage is thru various vv (e.g. splenic) which all lead to hepatic portal v

Small intestine  3       Duodenum = 2ndary                                        Digestion of nutrients,                 T5-9 symp fibers via        Sup & inf mesenteric a,
parts = duodenum (first   retroperiotneal                                          absorption of nutrients,                greater splanchnic n to     sup mesenteric v
10 in), jejunum (next 8   Jejunum & Ileum =                                        reduction of bacterial load in          celiac ganglion; post
ft), ileum (last 12 ft)   intraperitoneal                                          small gut                               vagal trunks (parasymp)
Large intestine          Ascending, descending                                    Store feces for disposal,               T10-L3 symp fibers via      Sup & inf mesenteric a
ascending, transverse,    = secondary                                              absorption of water and                 greater splanchnic n to
descending, sigmoid       retroperitoneal                                          electrolytes; protec body from          celiac, superior
colons                    Transverse, sigmoid =                                    massive numbers of bacteria in          mesenteric, and inferior
                          intraperitoneal                                          colon                                   mesenteric ganglion;
                                                                                                                           vagus n and (parasymp)
   Jejunoileum – small intestine b/w the duodenum and cecum; beginning here, the small intestine is suspended from the post body wall by the mesentery, which also
    envelops the sup and inf mesenteric a which supply the entire small intestine and large intestines, as well as the sup mesenteric v which drains the small intestine of
    nutrient-rich blood and carries it to join the splenic v which contributes to the formation of the portal v; the interior contains muscular circular folds and mucous
    membrane containing intestinal villi.
   Jejunum = first 2/5 of the remaining small intestine; more muscular and a wider lumen; more vascular; less fat in its mesentery
   Ileum is the last 2/3 of the small intestine; smaller and narrower w/ more fat enclosed in its mesentery; ends at the ilececal jxn and ileocecal valve
   Special structures inside the small gut: Plicae circulares = large circular folds. Largest in jejunum, smaller in ileum; Villi = microscopic, finger-like projections.
    Longest in jejunum and smaller in ileum; Peyer’s patches = collections of B-cells and T-cells to protect against bacteria. Commonly seen in ileum, only occasionally
    seen in jejunum.
   Vascular and other differences in small intestine regions: Jejunum = few arcades (arches of anastomosing arteries), long vasa recta, tall plicae circulares; Ileum = more
    arcades, shorter vasa recta, few shallow plicae circulares, Peyer’s patches (becoming more abundant distally).
   Cecum = intraperitoneal blind pouch depending inf to the ileocecal jxn; has a thin tube (appendix = retrocecal or behind cecum; at T10 so referred pain felt at
    umbilicus) projecting off its medial aspect, located on the ant abdominal wall at the intersection of the R semilunar line and a line connect the R & L ASIS’s. Blood
    supply = sup mesenteric a.; Details of cecocolic structure = orifice of ileum (where B and T lymphocytes accumulate), frenulum, orifice of appendix
   4 features of the colon identifying if from the small intestine = 1. Teniae coli = longitudinal bands of muscle continuing along the colon; 2. Haustra = the teniae coli are
    slightly shorter than the entire length of the colon, therefore the walls of the colon are bunched up into pouch-like bulges called haustra; 3. Epiploic appendages = small
    pockets of peritoneum filled w/ fat. Depostited along the colon (at tenia coli) except at the rectum; 4. Semilunar fold = folds on internal surface
   Ascending colon = begins to absorb water from and forms fecal matter; it is retroperitoneal along the right side of the abdominal cavity. At the right lobe of the liver,
    the ascending colon takes a sharp 90 degree left turn = R colic (hepatic) flexture (flexure = sharp turn). Overlies the iliacus muscle, quadratus lumborum m, transverse
    abdominis m, and lower lateral aspect of the R kidney. Blood supply by the sup mesenteric a.
   Transverse colon = movable part of the large intestine. Begins at the hepatic flexure on the right and onctinues to the splenic flexure on the left, crossing ant to the
    duodenum and pancreas. Intraperitoneal, supported by the transverse mesocolon and attached to the entire length of the greater curavature of the stomach by the
    gastrocolic lig of the greater omentum; the omental apron is attached to and depends from the inf border of the transverse colon. At the left lobe of the liver, the
    transverse colon makes a sharp 90 degree right turn = left colic (splenic) flexure. Blood supply = sup & inf mesenteric a. has 3 tenia coli mm. Gastrocolic lig, transverse
    mesocolon, and greater omentum attached to it.
   Descending colon = begins at the left colic flexure and descends along the left post abdominal wall. Usually lies retroperitoneally, and is usually the narrowest part of
    the colon; occasionally possesses a partial mesocolon. Descends over the lateral border of the L kidney, quadratus lumborum, and across the iliacus and psos mm into
    the iliac fossa to the pelvic brim. Blood supply = inf mesenteric a.
   Sigmoid colon = intraperitoneal, supported by the sigmoid mesocolon, but fixed at its jxns w/ the descending colon and rectum. Enters the pelvic cavity at the level of
    S3 and continues into the rectum and from there into the anal canal. Blood supply = inf mesentery a.

Liver  largest gland        Intraperitoneal; loc                                     Produce bile to aid in digestion     T6-9 symp via celiac      Hepatic a
in body; fills dome of R upper R quadrant                                                                                  plexus; vagus n
diaphragm; highest pt                                                                                                      (parasymp), R phrenic n
at 5th rib; left margin                                                                                                    (sensory)
externds to pt below
apex of heart; inf
margin is oblique and
passes left to right to
level of 9th costal
cartilage; 4 lobes
Gall bladder  along         Intraperitoneal                                          Reservoir for bile; absorbs water T6-9 symp via celiac         Cystic a – br of R hepatic
w/ cystic duct forms a                                                                to cncentrate the bile               plexus; vagus n           a
diverticulum off the                                                                                                       (parasymp), R phrenic n
common hepatic duct                                                                                                        (sensory)
 Liver: Diaphragmatic surface = large dome-shaped surface apposed to the under surface of the diaphragm; lies in contact w/ the R lung, the pericardium, and at its left
     extremity, with the L lung; contains the coronary ligament, the left and right triangular ligs, and the bare spot (where diaphragmatic peritoneum becomes coronary
     ligament), and the sulcus for the IVC.
 Visceral surface = faces downward, backward, and to the left; lies in relation top and contains the impressions for the stomach, duodenum, right colic flexure, right
     kidney and suprarenal gland, and the gall bladder lodged in its surface; the porta hepatis also lies on this surface.
 The porta hepatis = the entrance to the liver; includes portal v, the hepatic a, and the common bile duct
 Lobes of the liver = porta hepatis, gall bladder, IVC, and the fissure for the ligamentum teres and venosum together form an ―H‖ which separtes the liver into 4 lobes:
           o Right lobe= contains right renal and colic impressions; loc to right of falciform lig
           o Left lobe = contains the gastric impression; loc to left of falciform lig
           o Quadrate lobe = along the inf border lying in relation to the gall bladder; loc b/w ligamentum teres and gall bladder
           o Caudate lobe = along the superior margin in relation to the IVC; loc b/w IVC and ligamentum venosum
 Anatomical division for left and right lobes = line formed by falciform ligament and ligamentum teres; physiological division based on vascular supply and ducts
     supplying the organ (where they bifurcate into left and right vessels/ducts)
 Peritoneal relations: Falciform ligament = remnant of the ventral mesogastrium attaching the liver to the abdominal wall; its free inf margin encloses the ligamentum
     teres, the obliterated umbilical v (as it bypassed the liver to get to the IVC).
 Coronary ligament = the reflected layers of diaphragmatic peritoneum onto the liver; encloses the bare spot, and extends laterally to form the right and left triangular
 Lesser omentum = persisting portion of the ventral mesogastium connecting the liver with the lesser curvature of the stomach and the 1st part of the duodenum
 Internal liver morphology: Hepatic a = conducts blood (from celiac trunk) into liver to nourish its tissues; branches into large left and right hepatic arteries to each lobe
   Hepatic porta vein = brings nutrient rich blood from the gut into the liver for detoxification; sends blood from GI tract to liver, where it joins arterial blood to supply the
    sinusoids (enlarged capillaries); transports bilirubin (breakdown of RBCs) from spleen, glucose and amino acids fromsmall intestine, toxins & drugs absorbed in
    stomach and small intestines, insulin & glucagons from pancreas
   Hepatic ducts = right and left hepatic ducts merge to form common hepatic duct, which joins w/ the cystic duct of the gall bladder to conduct bile to the duodenum
   Hepatic vv = usually 3 vv (left, middle, right); converge on the IVC in its fossa ont eh visceral surface
   Radicles (branches) of the hepatic a, portal v, and hepatic ducts distribute together w/in the lobules of the liver, and the hepatic vv drain the lobules into the IVC
   Structure of gall bladder: Fundus = bulbous end; Body = tapering toward the neck; Neck = points upward toward the porta and feeds into the cystic duct; Cystic duct =
    feeds into the common hepatic duct to form the common bile duct at the porta hepatis; Bile duct sphincter = near the duodenum; constricts to stop flow of bile and
    divert it into the gall bladder.
   Flow of bile = liver produces bile (in hepatocytes), which is used in digestion for emulsification of fats (improves absorption). Bile leaves via hepatic bile ducts. Bile
    enters gall bladder via cystic duct. Gall bladder concentrates and stores bile. Bile secreted to 2nd part of duodenum via common bile duct.
   Biliary tree = gall bladder, common hepatic duct (bile from L & R lobe of liver), cystic duct (bile to or from gall bladder), common bile duct (common hepatic duct +
    cystic duct), hepatopancreatic duct (common bile duct + main pancreatic duct), main pancreatic duct (from pancreas).
   Blockage of portal v  there are shunts that go around it = portacaval anastomoses; blockage can be due to cirrhosis of liver and cause high pressure in portal v. blood
    can back up to several places  3 places of anstomoses = umbilicus, esophagus (w/ gastric v of stomach), rectoanal region vv (w/ sup rectal vv)
   Locations for gall stones = within gall bladder; in cystic duct; in common bile duct; in hepatopancreatic duct

KIDNEY, SPLEEN,             SUPRARENAL                   GLAND
Spleen  part of            Intraperitoneal in upper                                Removes old RBC                 T6-8 symp via celiac          Splenic a
lymphatic system;           abdomen                                                                                 plexus
bound by spleenorenal
& gastrosplenic ligs;
borders omental bursa;
covered by diaphragm
Kidneys L kidney           Retroperitoneal in sup                                  Eliminate waste; regulate       T11-12 symp via renal         Interlobar a, interlobular
higher than R b/c liver     part of abdomen                                         volume of blood; regulate       plexus; vagus n               a, renal a, arcuate a,
pushes down R kidney;                                                               electroly balance in blood;     (parasymp)                    segmental a
sup poles of L kidney at                                                            production of hormones (i.e.
11th rib and R kidney at                                                            Renin)
11th intercostal space;
partly covered by 12 rib
and psoas major m;
hilus at L1 level; inf
pole at L3
Suprarenal gland            Loc retroperitoneal near                                Cortex = secretes steroid       Celiac plexus (symp) via Inferior phrenic a, aorta,
(adrenal gland)            sup pole of kidneys but                                 hormones (e.g. aldosterone,     thoracic splanchnic nn        inferior suprarenal a,
cortex & medulla;           often observed b/w                                      cortisol, etc)                                                superior suprarenal a,
covered by extensions       kidneys and vertebrae                                   Medulla = secretes epi & norepi                               middle suprarenal a,
of renal fascia but                                                                 (postganglionic part of symp)                                 renal a
separated from kidney
 KIDNEYS: Ureters (carry urine from kidneys to urinary bladder) arise from hilus of kidneys; produces urine = ultrafiltrate of blood in renal a; first part of ureter =
     renal pelvis; hilum contains renal a, renal v, and renal pelvis; have bumps from development = lobules
 Fascial compartment = pararenal fat (below parietal peritoneum), renal fascia (dense CT deep to pararenal fat), perirenal fat (fatty renal capsule around kidney), fibrous
     fascia (fibrous, dense CT capsule of kidney)
 Relationships of posterior kidneys: superior pole w/ diaphram; medial part w/ psoas major; central part w/ quadratus lumborum; lateral part w/ transversalis fascia
 Superior pole of kidneys associates w/ bare area of liver; left kidney related w. spleen and pancreas  splenic a & v b/w L kidney and pancreas
   Kidney’s and suprarenal glands are behind parietal peritoneum = retroperitoneal; suprarenal glands are separated from diaphragm (sup to it) by diaphragmatic fascia
   Kidney surface divisions = Anterior side: superior (apical), anterior superior, anterior inferior, inferior segments; Posterior side: superior, posterior, inferior segments
   Kidney internal structure: Cortex (outer part of kidney); Medulla (inner kidney); Pyramid (made up of nephrons) = Medulla & Papilla (apex of pyramid; where urine
    comes out from after being made); Renal Column (b/w pyramids; looks like cortex); Major Calyx; Minor Calyx; Renal Pelvis (continues into ureter)
   Nephrons filtrate blood of renal a  ultrafiltrate sent to medullary pyramid  papilla  exits into minor calyx  major calyx  renal pelvis
   Renal a comes in thru hilus (usually divides into ant and post brs before entering hilus) post to renal v  brs into segmental a (go to diff segments of kidney)  brs
    into interlobar a  arcuate a interlobular a
   Inferior relationships of spleen (on ant surface) = covered by diaphragm (behind diaphragm are ribs 9-11)
   Visceral relationships of spleen (on post surface) = gastric impression; hilus (splenic a & v); renal (left kidney) impression; left colic (splenic) flexure impression
   Cross section of spleen: spleen covered serosa (visceral peritoneum)deep to it is fibrous capsule  deep to is splenic pulp  central is the splenic trabeculae
    (surrounding the hilum; carry blood vessels to the pulp)

ABDOMINAL                  AORTA, IVC, AND              ABDOMINAL                    AUTONOMICS
 Descending Abdominal Aorta = loc near center of vertebrae slight to left; begins by penetrating the crus of the diaphragm at T 12 level; terminates ar around L4 level
   by dividing into common iliac aa
 All intestinal blood flow passes thru portal v to the liver, and ultimately enters IVC thru hepatic vv
 Abdominal lymphatics follow aorta, ascending from the pelvis in the 2 trunks (lumbar nodes), until they fuse together and w/ the intestinal trunk to form the thoracic
   duct; include thoracic duct, intestinal trunk, R lumbar nodes and lymph chain, L lumbar nodes and lymph chain, common iliac nodes, internal iliac nodes, external iliac
Abdominal autonomics:
 Sympathetics: Pregangs arise from cord, including greater splanchnic N (T5-9), lesser splanchnic n (T10-11), least splanchnic n (T12), and lumbar splanchnic nn (L1-
   2). Greater, lesser, and least splanchnic nn will all synapse in ganglia: the celiac ganglion supplies the foregut, and nn follow brs of the celiac a. The superior
   mesenteric ganglion sends postgang fibers w/ the brs of the sup mesenteric a to the midgut. Aorticorenal ganglion receives some of these splanchnic n fibers, and
   supplies kidney and suprarenal glands. Lumbar splanchnics principally enter inf mesenteric ganglion and supply pelvis and hindgut via the aortic plexus and the
   hypogastric plexus (which goes into the pelvis).
 Parasympathetics: Arise from vagus n, or pelvis splanchnic nn w/ pregang axons. Vagus n supplies all forgut and midgut. It enters via the ant and post vagal trunks of
   esophagus, supplying esophagus and stomach. These follow celiac a, to supply foregut, some fibers continuing to aorta and on to sup mesenteric a, supplying midgut.
   Hindgut and pelvic organs are directly supplied via parasympathetic axons in the inf hypogastric plexus. Pelvic splanchnics follow up the hypogastric plexus. They
   reach colon by ascending rectum into sigmoid and then descending colon. Other pelvic organs are directly supplied via parasymp axons in the inf hypogastric plexus.
   Vagal parasymp’s follow celiac a to foregut. Some vagal parasymps follow sup mesenteric a to midgut. Pelvic splanchnics use inf hypogastric plexus to reach hindgut,
   bladder, etc.
Nerves                    Effect of Lesion   Origin                 Innervation Site          Course
Vagus n = CN X --> part                      Medulla of brainstem   Sensory: pharynx,         Exit from jugular foramen, passes inf in the
of parasympathetics                                                 larynx, thoracic &        neck w/in post part of carotid sheath in angle
                                                                    abdominal organs,         b/w IJV and common carotid a; enters
                                                                    tongue, epiglottis;       superior mediastinum  Rt vagus n passes
                                                                    Motor: pharynx,           ant to the first part of the subclavian a and
                                                                    intrinsic laryngeal       post to the brachiocephalic v and SC joint to
                                                                    mm, heart,                enter thorax. Lt. Vagus n descends b/w the left
                                                                    esophagus, lungs,         common carotid & lt subclavian a and post to
                                                                    bronchii, GI tract        the SC joint to enter the thorax, continues into
                                                                                              abdomen. Gives recurrent laryngeal and forms
                                                                                              cardiac, pulmonary, esophageal plexuses, &
                                                                                              celiac plexus
Ansa cervicalis n                            Ventral rami of C1-3   Infrahyoid Strap mm,      The loop has a superior root (C1) attached to
                                                                    geniohyoid m,             the outside of the carotid sheath and an
                                                                    omohyoid m               inferior root  loop can be short or long and
                                                                    motor n                   inf root can be superficial or deep to int
                                                                                              jugular v; superior root joins the hypoglossal n
Cervical plexus                              C1-4                   Scalene mm                Roots exit b/w anterior and middle scalene
                                                                                              mm (sup parts of mm)
Phrenic n                                    C3-5                   Sole motor n to           Formed at lat borders of ant scalene mm,
                                                                    diaphragm and             descends ant to ant scalene mm under cover of
                                                                    sensory to central        IJV and SCM; pass under prevertebral layer of
                                                                    diaphragm & heart; R      deep cervical fascia b/w subclavian aa and vv;
                                                                    n is sensory to liver     proceed to thorax thru mediastinum b/w
                                                                    & gall bladder            pleura and pericardium to diaphragm
Lesser occipital n                           C2-4                   Cutaneous                 Wind around post border of SCM
                                                                    innervation to the
                                                                    scalp above the ear
Greater auricular n                          C2-4                   Cutaneous                 Wind around post border of SCM
                                                                    innervation to ear-
                                                                    auricle, behind ear, in
                                                                    front of ear
Transverse cervical n                        C2-4                   Cutaneous                 Wind around post border of SCM
                                                                    innervation to ant
                                                                    triangle of neck
Supraclavicular n                            C2-4                   Cutaneous                 Wind around post border of SCM
                                                                    innervation to
                                                                    shoulder, upper chest,
                                                                    and root of neck
Accessory n (CN XI)                          Medulla oblongata      SCM, trapezius,
Trigeminal n (CN V)                          Medulla oblongata      Anterior digastric m
Facial n (CN VII)                            Medulla oblongata      Platysma m, posterior
                                                                    digastric m
Hypoglossal n (CN XII)                       Medulla oblongata      Intrinsic and extrinsic   Temporarily joined by superior root (C1
                                                                                               mm of tongue             fibers) of ansa cervicalis
Recurrent Laryngeal nn =     Lesion one side = hoarseness             Vagus n in inf part of   Motor n to Intrinsic     Rt recurrent laryngeal n loops inf to rt
right and left nn            Lesion both sides = suffocation          neck (carotid sheath)    mm of larynx except      subclavian a at approx t1-2 level and left
                                                                                               cricothyroid             recurrent laryngeal n loops inf to the arch of
                                                                                                                        aorta at approx T4/5 level. Ascend sup’ly to
                                                                                                                        posteromedial aspect of thyroid gland and
                                                                                                                        ascend in the tracheoesophogeal groove to
                                                                                                                        supply laryngeal mm
Cervical sympathetic         Cervical lesion of symp trunk = horner   Receive pregang          Fascial viscera (e.g.    Connect to sympathetic chain via gray rami
ganglia = superior,          syndrome  constriction of pupils        fibers from superior     eyes)                    communicantes; inf ganglion may fuse w/ T1
middle, and inferior                                                  thoracic spinal nn and                            ganglion to form cervicothoracic ganglion 
                                                                      assoc white rami                                  lies ant to trans process of C7, just sup to neck
                                                                                                                        of 1st rib on each side and post to origin of
                                                                                                                        vertebral a
Ansa subclavia n – part of                                                                                              Comes off of middle cervical ganglion, loops
sympathetic chain                                                                                                       around subclavian a, and connects to inferior
                                                                                                                        cervical ganglion.
Intercostal nn ventral                                               Ventral rami of          Mm of corresponding      Follow intercostal space in dermatomes;
rami of T1-11                                                         thoracic spinal nn       intercostal space and    course in costal grooves b/w internal and
Thoracic intercostal= 1-6                                                                      overlying skin (ant      innermost intercostal mm w/ posterior
Thoracoabdominal                                                                               thorax) and part of      intercostal vv and aa; gives lateral (divides
intercostals = T7-11                                                                           abdomen; sensory to      into post and ant brs) and anterior (divides
Subcostal = T12                                                                                peripheral diaphragm     into med and lat brs) cutaneous brs (T2 =
Attach to symp trunk via                                                                                                intercostobrachial n) near midaxillary line and
rami communicantes                                                                                                      sternum; gives collateral br near angle of rib
Greater splanchnic n                                                  Preganglionic fibers     Viscera of               Presynaptic symp fibers pass thru
                                                                      of T5-9                  abdominopelvic           abdominopelvic splanchnic n to prevertebral
                                                                                               cavity                   ganglia where they synapse
Lesser splanchnic n                                                   Preganglionic fibers     Viscera of               Presynaptic symp fibers pass thru
                                                                      of T10-11                abdominopelvic           abdominopelvic splanchnic n to prevertebral
                                                                                               cavity                   ganglia where they synapse
Least splanchnic n                                                    T12 preganglionic        Viscera of               Presynaptic symp fibers pass thru
                                                                      fiber                    abdominopelvic           abdominopelvic splanchnic n to prevertebral
                                                                                               cavity                   ganglia where they synapse
Celiac ganglion                                                                                Stomach, liver,          Prevertebral ganglion where presynaptic symp
                                                                                               pancreas, spleen         fibers synapse w/ postganglionic fibers
Aorticorenal ganglion                                                                          Kidneys, adrenal         Prevertebral ganglion where presynaptic symp
                                                                                               cortex                   fibers synapse w/ postganglionic fibers
Superior mesenteric                                                                            Large intestine, small   Prevertebral ganglion where presynaptic symp
ganglion                                                                                       intestine, rectum,       fibers synapse w/ postganglionic fibers
                                                                                               internal anal
Inferior mesenteric                                                                            Bladder, penis,          Prevertebral ganglion where presynaptic symp
ganglion                                                                                       clitoric, gonad          fibers synapse w/ postganglionic fibers
Cardiac plexus                                                        Cervical& cardiac brs    Heart (SA node)          From arch of aorta and post surface of heart,
                                                                      of vagus n & symp                                 fibers extend along coronary aa and to SA
                                                                      trunk (postganglionic                             node; pain fibers travel with sympathetics via
                                                                            fibers from sup                                   white rami into upper thoracic spinal cord
                                                                            cervical plexus to T5
                                                                            of sympathetics;
                                                                            pregang fibers come
                                                                            from T1-T4/5)
Esophageal plexus                                                           Vagus n, symp             Smooth mm and           Distal to tracheal bifucation, the R & L vagus
                                                                            ganglia, greater          glnads of inf 2/3 of    and symp nn circle around esophagus to create
                                                                            splanchnic n              esophagus               the plexus and follow it down to diaphragm
Pulmonary plexus                                                            Vagus n and symp          Bronchi & lungs         Forms on root of lung and extends along
                                                                            trunk                                             bronchial subdivisions
Thoracoabdominal                                                            Ventral rami of T7-       Motor to abdominal      Pass medially in the neurovascular plane
intercostal nn                                                              11                        mm, sensory to          (interval b/ internal abdominal oblique &
                                                                                                      abdominal wall          transverse abdominis mm); lateral cutaneous
                                                                                                                              brs emerge in midaxillary ine and brs into
                                                                                                                              anterior brs (supply skin ventrally to border of
                                                                                                                              rectus abdominis m), post brs (supply skin
                                                                                                                              post’ly w/ corresponding dorsal rami), ant
                                                                                                                              cutaneous brs (penetrate rectus sheath near
                                                                                                                              midline and divide into short medial, longer
                                                                                                                              lateral brs to supply the skin over the rectus
Subcostal n                                                                 T12 ventral ramus         Skin over side of hip   Emerges post to ASIS and follows the inf
                                                                                                                              border of 12th rib, but no distribution to
                                                                                                                              thorax; crosses quadratus lumborum m deep to
                                                                                                                              tranversalis fascia to penetrate transverses
                                                                                                                              abdominis m; large lateral br passes
                                                                                                                              downward across iliac crest post to ASIS to
                                                                                                                              supply skin over side of hip
Iliohypogastric n                                                           L1 ventral ramus          Motor to abdominal      Emerges from latera border of psoas major,
                                                                            (freq contribution        mm; cutan brs to skin   crosses quadratus lumborum and pentrates
                                                                            from T12)                 over hip (suprapubic    transverses abdominis m near iliac crest; ant
                                                                                                      region, gluteal         cutan br pierces aponeurosis of external
                                                                                                      region)                 abdominal oblique m to distribute to skin of
                                                                                                                              suprapubic region; lateral cutan br crosses
                                                                                                                              iliac crest lateral to ASIS and descends to
                                                                                                                              supply skin of gluteal region post and lateral
                                                                                                                              to distribution of lat cutan br of subcostal n
Ilioinguinal n                                                              L1 ventral ramus as       Medial proximal         Passes b/w 2nd and 3rd layers of abdominal
                                                                            brs of lumbar plexus      thigh; scrotum          mm & thru inguinal canal; Emerges ant to
Gentiofemoral n genital                                                     Genitofemoral n           Testes
Ant scrotal nn                                                              Ilioinguinal n, genital   Scrotum
                                                                            brs (genitofemoral a)
   Sympathetics are important in glands and eyes b/c dilate pupils
   Sympathetic trunk = nerve ganglia chain that contain preganglionic and postganglionic motor (ventral root) fibers of sympathetic NS (T1-L2); presynaptic cell bodies
    lie in lateral horn of spinal cord and postsynaptic cell bodies lie in para- or pre-vertebral ganglia; lie anterolateral to vertebral column; assoc w/ cervical & lumbar
    sympathetic ganglia via gray rami preganglionic fibers leave spinal cord thru ventral root and enter ventral rami of spinal nn T1-L2 and then pass thru sympathetic
    chain via white rami and synapse w/ postganglionic fibers; postganglionic fibers pass from paravertebral ganglia in sympathetic chain thru gray rami and enter all brs of
    spinal nn (ventral and dorsal rami) or from prevertebral ganglia to effector site.
   Parasympathetic ganglia = nerve ganglia that contain preganglionic and postganglionic motor fibers of parasympathetic NS; presynaptic cell bodies located in medulla
    oblongata or sacral segments of spinal cord (S2-4); in the gray matter of the brainstem, the fibers exit w/in cranial nerves 3 (oculomotor), 7 (facial), 9
    (glossopharyngeal), & 10 (vagus) (cranial outflow); in the sacral regions, the fibers exit the spinal cord thru ventral roots of spinal nn S2-4 and pelvic splanchnic nn that
    arise from their ventral rami (sacral outflow); presynaptic fibers synapse with postsynaptic fibers in ganglia located at the effector site

Arteries                         Origin                              Blood Supply Site                  Course
Common Carotid a (R & L)         Right common carotid brs                                               Bifurcates into ext and int brs at C4 level; rarely above C3 or below
                                 from bifurcation of                                                    C5  only ext carotid has further brs in neck; lies deep to SCM;
                                 brachiocephalic trunk                                                  course parallel with internal jugular vv
                                 Left common carotid brs from
                                 arch of aorta
External carotid a               Common carotid a                    Face and neck (structures          Ant brs = superior thyroid, lingual, and facial aa; post brs = -
                                                                     external to the skull)             ascending pharyngeal, occipital, post auricular aa; courses post-
                                                                                                        sup’ly to region b/w neck of mandible and lobule (earlobe) of auricle
Internal carotid a               Direct continuation of              Brain                              Has brs inside the skull supplying the brain but NO neck brs
                                 common carotid a
Superior thyroid a               1st br of ext carotid a; most inf   Thyroid gland, infrahyoid mm,      Runs ant-inf’ly deep to infrahyoid m to reach thyroid gland; gives
                                 of ant brs                          SCM, parathyroid glands            rise to sup laryngeal a; gives ant and post brs  ant br descends
                                                                     (sometimes), larynx                along ant border otf thyroid gland and sends brs to ant surface (rt and
                                                                                                        lt brs anastamose at midline) and post br descends along post surface
                                                                                                        of thyroid gland and anastomoses w/ inf thyroid a
Lingual a                        Ant br of ext carotid a             Tongue                             Lies on middle constrictor mm of pharynx; arches sup-ant’ly and
                                                                                                        passes deep to hypoglossal n, stylohyoid m, and post belly of
                                                                                                        digastric m; disappears deep to the hypoglossus and turns sup’ly at
                                                                                                        ant border of this mm to become the deep lingual and sublingual aa
Facial a                         Ant br of ext carotid a             Palatine tonsil, palate,           Arises in common w/ lingual or immediately sup to it, gives off
                                                                     submandibular glands               tonsillar br as well as brs to palate and submandibular glands; passes
                                                                                                        sup’ly under cover of digastric and stylohyoid mm and the angle of
                                                                                                        the mandible; loops ant’ly and enters a deep groove in
                                                                                                        submandibular gland, hooks around middle of inf border of mandible
                                                                                                        and enters the face
Ascending pharyngeal a           Post br of ext carotid a  1st      Brs to pharynx, prevertebral       Ascends on pharynx deep to internal carotid a
                                 or 2nd br                           mm, middle ear, and cranial
Occipital a                      Post Br of ext carotid a; sup to    Scalp of back of head              Passes post’ly, parallel and deep to post belly of digastric m, forming
                                 origin of facial a                                                     its own groove in the base of the skull medial to that of the origin of
                                                                                                        the m, and ends in the post part of the scalp; during course it passes
                                                                                                        superficial to the int carotid a and CN 9 thru 11
Superior laryngeal a             Superior thyroid a                  Larynx                             Goes inside larynx
Inferior thyroid a               Thyrocervical trunk of              Thyroid gland; parathyroid         Curving a ascends and then runs medially and inf’ly post to
                                 subclavian a                        glands                             carotid sheath to reach post aspect of thyroid gland; divides into
                                                                                                        several brs that pierce pretracheal layer of deep cervical fascia and
                                                                                                        supply inf pole of the gland; gives br to ascending cervical a
Posterior auricular a                                                Mm adjac to mastoid process,       Ascemds post’ly b/w ext acoustic meatus and mastoid process to
                                                                parotid gland, facial n, struct in   supply adjac area
                                                                temporal bone, auricle and scalp
Thyrocervical trunk           Subclavian a (3rd br)                                                  Gives brs: transverse cervical, suprascapular, ascending cervical (via
                                                                                                     inf thyroid), and inferior thyroid aa
Costocervical trunk           Subclavian (2nd br)                                                    Gives brs: superior intercostal a, deep cervical a
Subclavian a (R & L)          Right = Brachiocephalic a         Upper limb via axillary a            Gives off vertebral a, internal thoracic a, thyrocervical trunk,
                              Left = arch of aorta                                                   costocervical trunk, and dorsal scapular a; course parallel to
                                                                                                     subclavian v; pass post to ant scalene m, and post-inf to clavicles
Brachiocephalic a             Arch of aorta                                                          Bifurcates into r. common carotid a and r. subclavian a.
Arch of aorta                 Continuation of ascending         Upper limb, neck, head, brain        Gives off brachiocephalic a, left common carotid a, and left
                              aorta                                                                  subclavian a; arches post’ly on left side of trachea and esophagus
                                                                                                     ande sup to left main bronchus
Vertebral a                   Subclavian a (1st br)             Brainstem (15% of blood supply       1st branch; ascends up cervical transverse foramen of C6 thru C1
                                                                to brain)
Superior intercostal a        Costocervical trunk of            1st and 2nd intercostal spaces
                              subclavian a
Deep cervical a               Costocervical trunk of            Deep back                            Gives rise to first 2 post intercostal aa
                              subclavian a
Internal thoracic a           Subclavian a (4th br)             Mammary glands and intercostal       Gives off mammary brs; pass inf’ly and lateral to sternum b/w costal
                                                                spaces via ant intercostal aa        cartilages and internal intercostal mm to divide into superior
                                                                                                     epigastric & musculophrenic aa at bottom of rib cage
Anterior intercostal aa       Internal thoracic a (&            Corresponding intercostal spaces     Pass b/w internal and innermost intercostal mm
(superior and inferior brs)   musculophrenic a)                 & intercostal mm; overlying
                                                                skin; parietal pleura; abdomen
Posterior intercostal aa      Aorta – 1 & 2 orginate from       Corresponding intercostal spaces     Anastomose ant’ly w/ ant intercostal brs of internal thoracic a in
(superior and inferior brs)   superior intercostal a and 3-11   & intercostal mm; overlying          lateral wall; course in costal groove b/w int & innermost intercostal
                              are direct brs of descending      skin; parietal pleura; supply        mm with intercostal nn and vv; right brs cross over vertebral bodies
                              aorta (11 total)                  esophagus; abdomen (10th-11th)       to get to right side b/c aorta is skewed to left of vertebral bodies; left
                                                                                                     brs come off of post aorta; give lateral and ant cutaneous brs
Collateral intercostal aa     Intercostal aa                    Intercostal spaces and mm;           Course at bottom of costal groove; expand to supply intercostal
                                                                overlying skin                       space if main aa are blocked
Ascending aorta               Aortic orifice of L ventricle     Heart                                Ascends approx 5 cm to sternal angle & becomes of arch of aorta;
                                                                                                     gives R & L coronary brs
Descending aorta              Continuation of Arch of aorta     Intercostal spaces & mm,             Descends in post mediastium to left of vertebral column; gradually
                                                                esophagus, bronchii, diaphragm       shifts to right to lie in median plane at aortic hiatus; give rise to post
                                                                                                     intercostal aa (T3-11), subcostal a, esophageal brs, bronchial aa, sm
                                                                                                     sup phrenic a; in abdomen: midline aa = gives off celiac a, sup
                                                                                                     mesenteric, inf mesenteric, median sacral a & lateral aa = inf phrenic
                                                                                                     aa, renal aa, gonadal aa, lumbar segmental aa, common iliac aa;
                                                                                                     abdominal aorta begins by penetrating crus of the diaphragm at T12
                                                                                                     level and terminates at L4 level by dividing into common iliac aa
Pericardiacophrenic a         Internal thoracic a               Diaphragm                            Parallels phrenic n
Superior epigastric a         Internal thoracic a               Rectus abdominis mm; sup part        Descends in rectus sheath deep to rectus abdominis mm;
                                                                of anterolateral abdominal wall      anastomoses w/ inf epigastric w/in rectus sheath deep to mm
Musculophrenic a              Internal thoracic a               Diaphragm, upper abdominal           Travels above diaphragm
                                                                wall, supplies twigs along costal
Superior phrenic aa              Ant part of descending aorta       Diaphragm                            Arise at aortic hiatus and pass to sup aspect of diaphragm; pass to
                                                                                                         post surface of diaphragm & anastomose w/ musculophrenic &
                                                                                                         pericardiacophrenic aa
Bronchial aa (2 on L and 1 on    Sm brs of ant aorta (left) or      Bronchi and lung tissue (w/ oxy      Run w/ tracheaobronchial tree
R)                               posterior intercostal aa (right)   blood); visceral pleura
Pulmonary trunk                  R ventricle                        Lungs (w/ deoxy blood)               Gives rise to 2 pulmonary aa, one to each lung; carries deoxygenate
                                                                                                         blood to lungs
Subcostal (T12) a                Descending aorta                   Mm of anterolateral abdominal        Courses along inf border of 12 rib
Right coronary a                 Right aortic sinus                 Right atrium, SA & AV nodes;         Follows coronary (AV) groove b/w the atria and ventricles;
                                                                    post part of IV septum               anastomoses w/ circumflex and ant IV brs of L coronary a
SA nodal br of                   R coronary a (near origin)         Pulmonary trunk and SA node          Ascends to SA node
R marginal a                     R coronary a                       Right ventricle & apex of heart      Passes to inf margin of heart and apex; anastomoses w/ IV brs
Posterior interventricular a     R coronary a                       R & L ventricles and IV septum       Runs from post IV groove to apex of heart; anastomoses w/
                                                                                                         circumflex and ant IV brs of L coronary a
Left coronary a                  Left aortic sinus                  Most of L atrium and ventricle;      Runs in AV groove and gives off anterior interventricular (LAD) and
                                                                    IV septum; AV bundles                circumflex brs; anastomoses w/ R coronary a
Anterior interventricular        L coronary a                       R & L ventricles and IV septum       Passes along ant IV groove to apex of heart; anastomses w/ post IV
(LAD) a                                                                                                  br of R coronary a
L marginal (obteuse) a           Circumflex a of L coronary a       Left ventricle                       Follows left border of heart; anastomoses w/ post & ant IV a
Circumflex a                     L coronary a                       L atrium and ventricle               Passes to left in AV groove and runs to post surface of heart;
                                                                                                         anastomoses w/ R coronary a
Esophageal aa                    Ant part of descending aorta       Esophagus                            Run ant’ly to esophagus
Inferior epigastric a            External iliac a                   Rectus abdominis m, medial part      Ascending br of external iliac a that enters rectus sheath from below;
                                                                    of ant-lat abdominal wall            anastomoses w/ sup epigastric a w/in rectus sheath deep to rectus
                                                                                                         abdominis m  anastomose joins subclavian a w/ the external iliac a
                                                                                                         and provides a route for blood to supply lower limb when the aorta
                                                                                                         becomes occluded
External iliac a                                                    Abdominal wall & lower limb          Give rise to inf epigastric and deep circumflex epigastric a
Deep circumflex epigastric a     External iliac a                   Deep tissues of abdominal wall;      Runs on deep aspect of ant abdominal wall, parallel to inguinal lig
                                                                    inf part of ant-lat abdominal wall
Superficial epigastric a         Femoral a                          Subcutaneous tissue and skin         Arises from ant aspect of femoral a ~ 1 cm below inguinal lig;
                                                                    over suprapubic region               ascends over inguinal lig and courses toward the umbilicus;
                                                                                                         anastomoses w/ inf epigastric a and superficial epigastic a on other
                                                                                                         side; runs in superifical fascia towards umbilicus
Superficial circumflex iliac a   Femoral a                          Subcutaneous tissue and skin         Arises ~1cm below inguinal lig lateral to superficial epigastric a;
                                                                    over inf part of ant-lat abdominal   pierces the fascia lata and ascends parallel to the inguinal lig to
                                                                    wall                                 upper thigh; runs in superficial fascia along inguinal lig
Superficial external pudendal    Femoral a                          Suprapubic region; prox parts of     Arises from medial aspect of femoral a ~2cm below the inguinal lig;
a                                                                   external gentalia                    crosses the spermatic cord (round lig of uterus) to supply its sites
Deferential a                    Inferior vesicle a                 Ductus deferens
Testicular a                     Descending aorta                   Testis and epididymis
Cremasteric a                    Inferior epigastric a              Cremasteric m                        Emerges in superficial inguinal r
Round ligament a
Celiac trunk                     Descending aorta (distal to        Esophagus, stomach, duodenum,        Divides into L gastric, splenic, and common hepatic a
                                 aortic hiatus of diaphragm)        liver, biliary apparatus, pancreas
L gastric a                 Celiac trunk                      Lesser curvature of stomach,     Runs in lesser omentum to the cardia and then turns abruptly to
                                                              distal portion of esophagus      course along the lesser curvature of the stomach and anastomose w/
                                                                                               the R gastric a
R gastric a                 Proper Hepatic a                  Stomach                          Runs to the left along the lesser curvature to anastomose w/ L gastric
Gastroduodenal a            Common hepatic a                                                   Gives 2 terminal brs = R gastroomental, superior
                                                                                               pancreaticoduodenal a, retroduodenal a
Short gastric a             Splenic a in hilum of spleen      Fundus of stomach                Pass to fundus of stomach
                            (distal part)
R Gastroomental a           Gastroduodenal a (1 of 2          R greater curvature of stomach   Runs to the left along the greater curvature to anastomose w/ the L
                            terminal brs)                                                      gastroomental a
L gastroomental a           Splenic a                         L greater curvatue of stomach    Course along greater curvature to anastomose w/ R gastroomental a
Proper hepatic a            Common hepatic a                  Liver, gallbladder, stomach,     Divides into right and left hepatic a
                                                              pancreas, duodenum, and
                                                              respective lobes of liver
Cystic a                    Right hepatic a                   Gallbladder, cystic duct
Common hepatic a            Celiac trunk                                                       Passes to porta hepata; gives gastroduodenal br & continues as
                                                                                               proper hepatic a
Retroduodenal a             Gastroduodenal a                  Post duodenum & pancreas?        Descends post to duodenum to pancreas ?
Sup pancreaticoduodenal a   Gastroduodenal a                  Distal portion of duodenum and   Ascends on head of pancreas; anastomose w/ inf
(ant and post)                                                head of pancreas                 pancreaticoduodenal a and pancreatic br of splenic a around
Splenic a                   Celiac trunk                      Body of pancreas, spleen,        Gives rise to short gastric a, L gastroomental a, pancreatic aa; runs
                                                              greater curvature of stomach     along sup border of pancreas; then passes to hilum of spleen;
                                                                                               pancreatic aa form archades w/ pancreatic brs of gastroduodenal and
                                                                                               superior mesenteric aa
Superior mesenteric a       Descending aorta                  Jejunum, ileum, cecum,           Branches = middle colic a, right colic a, ileocolic a, jejunal brs, ileal
                                                              appendix, ascending colon,       brs, appendicular a, anterior cecal a, posterior cecal a, inf
                                                              proximal ¾ of transverse colon   pancreaticoduodenal a; brs off of aorta inf to celiac trunk and runs
                                                                                               toward ileocecal jxn
Inferior mesenteric a       Descending aorta                  Hindgut (last ¼ of transverse    Branches = left colic a, sigmoid aa, superior rectal a; descends left of
                                                              colon, descending colon,         aorta
                                                              sigmoid colon, part of rectum)
Inf pancreaticoduodenal a   Superior mesenteric a             Distal part of duodenum and      Ascends head of pancreas; anastomose w/ sup pancreaticoduodenal
(ant and post)                                                head of pancreas                 and pancreatic br of splenic a around pancreas
Dorsal pancreatic a         Splenic a (pancreatic aa)         Pancreas (dorsal body)           Anastomose w/ sup & inf pancreaticoduodenal aa and pancreatic br
                                                                                               of splenic a around pancreas
Caudal pancreatic a         Splenic a (pancreatic aa)         Pancreas (tail)                  Anastomose w/ sup & inf pancreaticoduodenal aa and pancreatic br
                                                                                               of splenic a around pancreas
Pancreatica magna a         Splenic a (pancreatic aa)         Pancreas (body/tail)             Anastomose w/ sup & inf pancreaticoduodenal aa and pancreatic br
                                                                                               of splenic a around pancreas
Inf pancreatic a            Splenic a (pancreatic aa)         Pancreas                         Anastomose w/ sup & inf pancreaticoduodenal aa and pancreatic br
                                                                                               of splenic a around pancreas
Middle colic a              Superior mesenteric a (1st        Transverse colon                 Anastomose w/ inf aa of hindgut
                            main br on R side)
Right colic a               Sup mesenteric a (via iliocolic   Ascending colon                  Anastomose w/ inf aa of hindgut
                            a; 2nd main br on R side)
Ileocolic a                      Sup mesenteric a (terminal br    Iliocolic jxn                  Gives ileal br &, colic br (to iliocolic jxn), appendicular a, ant & post
                                 on R side)                                                      cecal aa; Anastomose w/ inf aa of hindgut
Jenjunal intestinal aa           Superior mesenteric a (L side)   Jejunum
Ileal intestinal aa              Superior mesenteric a (L side)   Ileum
Arterial arcades                 Intestinal aa (jejunum &         Jejunum, ileum                 Formed by uniting brs of intestinal aa; follow along border of small
                                 ileum)                                                          intestine
Vasa recta (straight arteries)   Arterial arcades                 Jejunum, ileum                 Longer in jejunum and shorter in ileum
Appendicular a                   Ileocolic a                      Appendix, cecum                Brs off to L of ascending colon and goes to mesoappendix
Anterior cecal a                 Iliocolic a                      Iliocecal jxn, cecum
Posterior cecal a                Iliocolic a                      Iliocecal jxn,cecum
Left colic a                     Inferior mesenteric a            Descending colon
Sigmoid aa                       Inferior mesenteric a            Sigmoid and descending colon
Superior rectal a                Inferior mesenteric a            Proximal rectum
Interlobular a                   Arcuate a                        Kidneys (cortex)               Microscopic straight aa br from arcuate a into cortex of kidney
Interlobar a                     Segmental a                      Kidneys (renal columns)        Form arcuate a (arches); b/w lobes (renal columns)
Renal a                          Descending aorta                 Kidneys; suprarenal glands     Post to Renal v b/c aorta is post to IVC; R renal a passes post to
                                                                                                 IVC; divdes close to the hilum into segmental aa (~5)
Arcuate a                        Interlobar a                     Kidneys                        Br into interlobular a; arcades at medulla-cortex jxn
Segmental aa of kidneys          Renal a                          Kidneys (segments)             Brs into interlobar a; go to diff kidney segments.
Inferior phrenic a               Descending aorta                 Diaphragm; suprarenal gland    Gives superior suprarenal br to adrenal glands
Inferior suprarenal a            Renal a                          Inf Suprarenal gland
Superior suprarenal a            Inferior phrenic a               Sup Suprarenal gland
Middle suprarenal a              Descending aorta (near SMA)      Middle Suprarenal gland
Veins                        Tributary                         Receiving Site                        Course
Internal Jugular v (R & L)   Brachiocephalic v (w/             Brain, ant face, cervical viscera,    Lies deep to SCM
                             subclavian v)                     deep back mm via superior and
                                                               middle thyroid vv
Superior thyroid v           Internal jugular v                Superior part of thyroid gland        Courses along with superior thyroid a
Middle thyroid v             Internal jugular v                Middle part of thyroid gland
Inferior thyroid v           Brachiocephalic v                 Inferior part of thyroid gland        Does not course with inferior thyroid a
Brachiocephalic v (R & L)    Superior vena cava                Inferior thyroid v, subclavian v,     Formed by uniting subclavian and internal jugular vv; left and right
                                                               and internal jugular v, T1            brachiocephalic vv unite to form superior vena cava; R v has a
                                                               intercostal v                         vertical course and L v has an oblique course
Subclavian v                 Brachiocephalic v (w/ IJV)        Axillary v                            Course ant to ant scalene m, and pass post-inf to clavicles
Superior vena cava           Right atrium                      L & R brachiocephalic vv;             Formed by uniting left and right brachiocephalic vv on right side
                                                               azygos v
Inferior vena cava           Right atrium                      From union of 2 common iliac v;       Ascends abdomen; does not receive direct tributaries from gut; all
                                                               Right side: hepatic, R inf            intestinal blood flow passes thru portal vv to liver and ultimately
                                                               phrenic, R middle suprarenal, R       enters IVC thru hepatic vv;
                                                               renal, R gonadal, R common
                                                               iliac, R internal iliac, R external
                                                               iliac vv; Left side: L inf phrenic,
                                                               L middle suprarenal, L renal, L
                                                               gonadal, lumbar segemtal, L
                                                               common iliac, L internal iliac, L
                                                               external iliac vv
Posterior intercostal vv     Internal thoracic v or            Intercostal spaces & mm               Course w/ post intercostal aa
                             hemiazygous system of vv
Azygos v                     SVC                               R superior Intercostal v, R           Collecting vv of right thorax and course vertically; gen loc on right
                                                               intercostal vv (T2-11), R             side of vertebrae; anastamoses w/ ascending lumbar v; drain left
                                                               subcostal v, hemiazygos v,            thorax too if hemiazygos vv absent
                                                               accessory hemiazygos v
Hemiazygos                   Azygos v                          L intercostal vv (T9-11), L           Collecting vv of left thorax and course vertically on left side of
                                                               subcostal v                           vertebrae; anastomoses w/ ascending lumbar v; can be
                                                                                                     developmentally connected w/ accessory hemiazygos v; cross
                                                                                                     midline to drain into azygos v
Internal thoracic v          Subclavian ?                      Ant intercostal spaces                Courses w/ internal thoracic a
Intercostal vv (T1-11)       Internal thoracic vv ant’ly and   Intercostal spaces & mm               Parallel intercostal aa and nn in costal groove b/w innermost and int
                             azygos v, hemiazygos v, &                                               intercostal mm
                             accessory hemiazygos v
Accessory hemiazygos v       Azygos v                          L Intercostal vv (T5-8)               Collecting vv of thorax and course vertically; can be
                                                                                                     developmentally connected w/ hemiazygos and L sup intercostal vv;
                                                                                                     cross midline to drain into azygos v
Pulmonary vv                 Left atrium                       Lungs                                 4 pulmonary vv, 2 from each lung; carry oxygenated blood to the
R superior intercostal v                                                                             Courses w/ R superior intercostal a ?
L superior intercostal v     L brachiocephalic v               Intercostal aa (T2-4)                 Loc on left side of thorax; can be developmentally connected w/
                                                                                                     accessory hemiazygos v
Great cardiac v              Coronary sinus                    Areas supplied by L coronary a        Parallels anterior interventricular a; becomes coronary sinus; drains
                                                                                                     backwards on posterior side
Middle cardiac v                 Coronary sinus                 Areas supplied by R coronary a       Parallels posterior interventricular a
Small cardiac v                  Coronary sinus                 Myocardium                           Parallels right marginal a
Coronary sinus                   Right atrium                   Coronary vv                          Receives blood from most major veins (great, middle, & small
                                                                                                     cardiac v, oblique v of L atrium, & post v of L ventricle) & dumps
                                                                                                     into right atrium
Anterior cardiac vv              Right atrium                   Ant surface of R ventricle           Drains directly to right atrium
Oblique v of L atrium            Coronary sinus                 L atrium                             Beginning of coronary sinus
Posterior v of L ventricle       Coronary sinus                 Post L ventricle
Thoracoepigastric v                                             Anterolateral body wall              Collateral pathway when IVC is blocked
Paraumbilical v                                                 Anterior abdominal wall (portal      Anastomose w/ superficial epigastric v (systemic system)
Superficial epigastric v         Great saphenous v                                                   Anastomose w/ paraumbilical v; collateral route
Superficial circumflex iliac v                                                                       Collateral route
External pudendal v
Greater saphenous v              Common iliac v                 Lower limb
Deferential v                                                   Ductus deferens
Pampiniform venous plexus                                                                            Venous network formed by up to 12 vv, draining into R or L
                                                                                                     testicular vv
Round ligament v                                                Round ligament
Hepatic v                        IVC                            Drains entire liver
Hepatic portal v                 Liver                          Stomach, small intestines,           In the liver, the blood joins arterial blood to supply the sinusoids;
                                                                pancreas, spleen, large intestines   located in porta hepatis and courses w/ hepatic a and common bile
                                                                                                     duct; located right of descending aorta; formed by uniting splenic
                                                                                                     and superior mesenteric v
Gastric vv                       Portal v                         Stomach
Splenic v                        Superior mesenteric v            Spleen and pancreas                  Forms hepatic portal v w/ superior mesenteric v
Superior mesenteric v                                             Small intestine & ascending and Forms hepatic portal v with splenic v
                                                                  transverse colon
Inferior mesenteric v            Splenic v                        Descending & sigmoid colon;
                                                                  sup rectum
Renal v                          IVC                              Kidneys; L testicular v
R testicular v                   IVC                              Testis
L testicular v                   L renal v                        Testis
 Venous angle –located where internal jugular v and subclavian v join to form brachiocephalic v  site where lymph trunk enters into venous system; R. side receives R
     jugular, R subclavian, and R bronchomediastinal trunks; L side receives L jugular, L subclavian, L bronchomediastinal trunks, and Thoracic duct
Lymphatics                                   Drainage Site                                 Course
Paracervical ring – all superficial nodes;   Superficial lymph from Face/chin/neck         Ring of lymph nodes around circumference of face/chin/neck area; lead to
helps stop infectious bacteria from                                                        deep cervical nodes that lie along jugular v
spreading too far
Occipital nodes                              Drains superficial lymph from occipital       Loc near occiput
Retro-auricular nodes                        Superficial lymph from behind ear             Loc behind the ear
Superficial parotid nodes                    Superficial lymph near parotid glands         Adjac to parotid glands
Buccal nodes
Submandibular nodes                          Superficial lymph from submandibular          Lies just lateral and behind submental nodes
Submental nodes                              Superficial lymph from below the chin         Lie just below the chin
Superficial cervical nodes                   Superficial lymph from region over SCM        Superficial to SCM
Jugulo-digastric nodes                       Superficial cervical lymph nodes              Drain to upper deep cervical nodes
Upper deep cervical nodes                    Superficial cervical lymph nodes              Drain to jugulo-omohyoid nodes
Jugulo-omohyoid nodes                        Superficial cervical lymph nodes              Drain to lower deep cervical nodes; lies where omohyoid m crosses jugular v
Lower deep cervical nodes                    Superficial cervical lymph nodes              Drains to jugular trunk
Jugular trunk                                Deep cervical lymph nodes                     Drains to venous angle
Paratracheal nodes                           Trachea                                       Send lymph to bronchomediastinal trunk
Tracheobroncheal nodes (sup & inf)           Loc near trachea – bronchi jxn                Drains to paratracheal nodes
Bronchopulmonary nodes                       Near primary – secondary bronchi jxn          Drains to tracheobroncheal nodes
Pulmonary (intrapulmonary) nodes             Lungs                                         Associate with higher bronchial divisions; drains to bronchopulmonary nodes
Bronchiomediastinal trunk                    Paratracheal nodes                            Drains lymph to L venous angle
Thoracic duct                                Origin = L lumbar trunk, R lumbar trunk, &    Ascends along vertebral column --> drains into venous system at L venous
                                             intestinal trunk (combine inf to diaphragm)   angle
                                             Drains all lymph from lower body
L & R lumbar trunk                           Lower extremities                             Thoracic duct
Intestinal trunk                             GI tract                                      Thoracic duct
Cysterna chili                                                                             Large sac-like struct loc at jxn of trunks forming thoracic duct --> holds lymph
                                                                                           in 40% of cases --> could spill contents if breaks
Pericardial nodes                         Cardia of stomach                                Sends lymph to left gastric nodes
Hepatic nodes                             Hepatic portal v                                 Sends lymph to pancreaticosplenic nodes
Pancreaticosplenic nodes                  Near fundus along greater curvature of           Sends lymph to celiac nodes
L gastric nodes                           At ant and post surface of lesser curvature  Sends lymph to celiac nodes
                                          of stomach near fundus/upper body
Celiac nodes                              At lower part of lesser curvature of stomach Receives all the lymph of the stomach
                                          inferior to gastric nodes
Pyloric nodes                             Pylorus of stomach                           Drains right 2/3 of inf 1/3 of stomach; sends lymp to celiac nodes
R gastroomental nodes                     At ant and post surface of greater curvature Drains to celiac nodes
                                          of stomach near antrum
 Vascular pattern lays down foundation for lymphatics
 Lymphatics remove excess tissue fluid (prevent accumulation of lymph = edema) --> one way valves throughout entire lymphatic system ensures one-way flow

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Description: MUSCLESTRUCT abdominal cavity