Equine Hind Limb _Part 2_ - College of Veterinary Medicine by suchenfz

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									Equine Hind Limb




 Reciprocal Apparatus, Stifle, Tarsus and Hip
                        Paragraphs 306-313
                              March 30, 2000
Announcements
• Do paragraphs 306-311 on one leg (the
  best specimen), and do paragraphs
  312-313 on the other.
• There will be a short “one-minute
  paper” at the end of the lecture today.




                                        2
Reciprocal Apparatus
• Involves fibrous bands which unite the distal
  femur to the tarsus/metatarsus.
  – peroneus tertius on the cranial side
  – superficial digital flexor and fibrous band in the
    gastrocnemius on the caudal side
• Functions to cause the stifle and hock to
  move in unison.
  – when the stifle flexes, the hock flexes; when the
    stifle extends, the hock extends
• Bottom line: if the stifle is fixed in position,
  the hock is fixed also.
                                                         3
             Peroneus Tertius and
S447
                 Cranial Tibial
           • Peroneus tertius (1 -
             yellow)
              – dorsal insertion on T3
                and MT III
              – lateral insertion on
                calcaneus and T4
           • Cranial tibial (2 - blue)
              – perforates distal end of
                the peroneus tertius
              – cunean tendon inserts
                medially on T 1&2
                                                     M
                 • cunean bursa
              – dorsal insertion on MT III
                                             ND622
       M                                             4
       Caudal Leg Muscles


       1. gastrocnemius
       2. popliteus
       soleus
       3. deep digital flexor
       4. lateral digital extensor
       5. superficial digital flexor
       location of calcaneal bursa


                                               5
S449                                   ND623
 Reciprocal Apparatus
                               patella
                               femur

                               tibia
                               superficial
                               digital flexor
                               peroneus
                               tertius

                               calcaneus

                               talus

                               metatarsus       6
From the Mediclip image bank
Reciprocal Apparatus




                       7
Reciprocal Apparatus




                       standing




                                  8
Reciprocal Apparatus




                       flexed




                                9
Ruptured Peroneus Tertius




                            10
Ruptured Peroneus Tertius




                            11
Comprehension Break: Examples

               (Extreme)
               flexion of both
               stifle and hock.

               Flexion of stifle
               with extension
               of hock.




                                   12
 Example Quiz Questions
1. The calcanean
   tendon keeps the
   hock from (flexing,
   extending) while
   the horse is
   bearing weight on
   that limb.
2. What part of the
  reciprocal
  apparatus is
  located here
  (cranial side of
  crus)?
  Peroneus tertius        13
Stay Apparatus of the Hind Limb
• Same principle as that for the forelimb:
  – horse is able to stand with minimal muscular
    effort required to keep limb joints from collapsing
• Key components:
  – patella and patellar ligaments (locks stifle)
  – caudal structures of the crus/tarsus (stabilize
    tarsus when stifle is locked)
     • tarsal ligaments, attachment of SDF to calcaneus,
       DDF with its check ligament, common calcanean
       tendon (gastrocnemius)
  – suspensory apparatus of the fetlock (same as
    forelimb)
• Bottom line: fixation of the stifle allows
  fixation of the tarsus; digit has suspensory
  apparatus.                                               14
Patellar Ligaments and Locking Mechanism
                  Patella in resting pos.
                   medial fibrocartilage
                   medial lig. (1‟)
                   middle lig. (1‟‟)
                   lateral lig. (1‟‟‟)
                  Patella slides on gliding surface
                  during movement.
                  Patellar fibrocartilage and medial
                  patellar ligament “lock” over
                  medial trochlear ridge.
                   This is an active process - involves
           S365    extension, & medial rotation of
                   patella
Stifle Joint - Medial View (ND 616)
                        1. patella
                        2. patellar fibrocartilage
                        4. med. trochlear ridge
                        5. middle patellar lig.
                        6. medial patellar lig.

                        These structures form
                          the locking mechanism
                          of the stifle; “2” and “6”
                          loop over the medial
                          trochlear ridge.

                                                     16
              medial
Stifle Joint - Lateral and Caudal (S368-9)

                med. patellar
                ligament
                biceps femoris
                femoropatellar lig.
                cran. cruciate lig.
                lat. collateral
                meniscofemoral
                lat. meniscus
                caud. cruciate lig.
                lat. patellar lig.

                                         17
           lateral
    Successive stages of patellar movement:
1                     2
                                              3




                                                  3



1                      2
Ligaments of the Tarsus (S371-2)
              1. collateral ligs.
              1”. short parts of 1
              2. long plantar lig.




 lateral                                       medial
                                     area of cunean bursa
                                     dorsal tarsal lig
                                                      19
Passive Stay Apparatus
• Hip is relatively balanced.
• Stifle locked with patellar              force of
                                           weight
  ligaments.
• Weight of trunk would tend to
  flex hock.
  – flexion prevented by tension in
    superficial digital flexor (red) and
    gastrocnemius (blue)
  – peroneus tertius (red) not
    involved in standing animal
  – stay apparatus of digit essentially
    same as that of forelimb
  – notice check lig. for deep digital         20
    flexor (green)
   Stifle Joints (S366)

• Stifle consists of the
  femoropatellar joint and
  the femorotibial joint.
  – femorotibial joint has both
    medial and lateral
    compartments
  – femoropatellar usually
    communicates with the
    medial femorotibial
    compartment; occasionally
    it also communicates with
    the lateral
  – in practice, treat all stifle
    joint compartments
                                  21
    separately
Tarsal Bones and Joints (after Dyce)
 Note: schematic diagram
                                        Tib.          F
  share a joint
  capsule                                                 Cal.
        tarsocrural                   Talus
                      proximal row
         proximal
         intertarsal
                  intermediate row             central
        distal                                             4
        intertarsal      distal row   1+2        3

          tarsometatarsal              II       III         IV

             occasionally
             communicate                                         22
Tarsocrural Joint Pouches                           dorsomedial
   lateroplantar              medioplantar




                                                                M
lateral malleolus

medial malleolus (and „3‟)                      (easily punctured, but
                             deep dig. flexor   avoid saphenous v.)
         Synovial Structures of
             Tarsus (ND 620)

  L




          cross section at arrows in A

medial                            24
Synovial Structures of Tarsus - Key
 1.    superficial digital flexor and associated bursae
 2.    gastrocnemius
 3.    deep digital flexor (and tarsal sheath in tarsal canal)
 5.    medial saphenous vein (cr. branch)
 6.    long digital extensor
 7.    peroneus tertius
 8.    cranial tibial (cunean tendon - 8‟)
 9.    proximal, middle and distal extensor retinacula
 10.   tarsocrural joint with two of three pouches showing
 11.   collateral ligaments
 14.   long plantar ligament
 15.   plantar nerves and saphenous vessels
 16.   cranial tibial vessels and deep peroneal nerve
                                                                 25
 18.   caud. cut. sural nerve, lat. saphenous vein
         Ligaments of Hip -
        Cranial View (S441)


transverse acetabular ligament
prepubic tendon
accessory ligament of head of
femur (orange)

(round ligament of head of femur is
not shown)




                                 26
Example Quiz Questions
1. (Breed?)
   Holsteiner

2. Which patellar
  ligaments can
  be palpated?
   All 3 can be
   palpated.

3. What artery is
  palpable here?
  (Lateral plantar) digital
                              27
One-Minute Paper (complete and turn in)
1. What topic was presented the most clearly today?




2. What topic was least well presented?




3. What would have improved today‟s lecture?



                                                      28
  One-Minute Paper Results, 3-29-00
1.What topic was presented        3. What would have improved today‟s lecture?
  the most clearly today?            29 Nothing, nothing listed or well done
  55 Reciprocal apparatus /          10 More time for the hind limb labs / add one
     animated pictures                  more lab / spread out material
  12 Patellar locking mechanism
                                     8 More time on synovial structures
     / stay apparatus
  4 Everything / well done           5 More time to draw on notes, especially
                                       radiographs / slow down
  1 Ligaments of hip
                                     5 Better handout (although “better than most”);
2.What topic was least well            list / label more structures / color copies
  presented?
                                     3 Schematic or model of locking mechanism /
  31 Synovial structures of            review stay apparatus
     tarsus / stifle
                                     2 Fewer tangents / less repetition in lecture
  13 Stay apparatus / patellar
     locking or movement             2 More real pictures, less illustrations
  8 Nothing / nothing listed         2 Sites for hock injections / hock diseases
  7 Accessory ligament of head         Miscellaneous: beer, more sleep (2), a Quarter
     of femur / hip ligaments          Horse; leave ½ of the room lights on; shorter
  3 Tarsal ligaments                   lectures; table to differentiate components of
                                       common calcanean tendon; don‟t ask quiz
  2 Blood flow (yesterday)             questions from next assignment; orient to
  1 Topics later in the lecture        illustrations before discussing them

								
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