Lab 8 by dffhrtcv3


									BIO 210 Lab Handout #8 – Articulations & Body Movements

Body Movements: every muscle (or other connective tissue structures) is attached to bone at two points; the origin is
stationary and the insertion is the moveable attachment. When the muscle contracts and the fibers shorten, the
insertion moves toward the origin.

Flexion – movement that decreases the angle of the
joint & lessens the distance between the two bones;
Joints – hinge, ball & socket

Extension – movement that increases the angle of a joint &
the distance between 2 bones or parts of the body; opposite of
Joints – hinge, ball & socket

Hyperextension – if extension is beyond the anatomical position or greater than 180o

Abduction – movement of a limb away from the midline of the body,
Joints - fanning movement of fingers or toes, ball & socket

Adduction – movement of a limb toward the midline of the
body; opposite of abduction

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Rotation – movement of a bone around its longitudinal axis
without lateral or medial displacement; Joints – Atlanto-axial, ball &

Circumduction – combination of flexion, extension, abduction &
adduction; proximal end of the limb remains stationary while the distal
end moves in a circle
Joints – ball & socket

Movements of the Hand

Pronation – movement of the palm of the hand from an
upward-facing position to a down-ward facing position; anterior
to posterior

Supination: - movement of the palm from a
posterior position to an anterior position; opposite of

Movements of the Foot

Dorsiflexion – movement of the ankle joint in a dorsal direction
(standing on one’s heels)

Plantar Flexion - movement of the ankle joint in
which the foot is flexed downward (standing on one’s toes;
pointing the toes)

Inversion – movement that results in the medial turning of the sole of the foot

Eversion – movement that results in the lateral turning of the sole of the foot: opposite of inversion

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Suture – irregular edges of the bones interlock & are united by very short connective tissue fibers
               1. Frontal
                                                                                         Sacroiliac joint
               2. Sagittal
               3. Lamboidal
               4. Squamous

Symphyses – bones are connected by a broad, flat disc of fibrocartilage
           1. Symphysis pubis
           2. Sacroiliac joint
           3. Intervertebral joints

                                                                                             Pubic symphysis

Synovial – joints in which the articulating bone ends are separated by a joint cavity containing synovial fluid; all are
characterized by the following structures
   1. Joint surfaces enclosed in a sleeve of fibrous connective tissue (articular capsule)
   2. Synovial membrane produces synovial fluid for lubrication; reduce friction
   3. Articulating surfaces of the bones are covered with hyaline cartilage
   4. Capsule is reinforced with ligaments
   5. Fibrocartilage pads may be present within the capsule
Hinge – rounded process of one bone fits into the concave surface of another to allow movement in one plane,
usually flexion and extension

1. Tibiofemoral (knee)- between the femoral condyles and the C-shaped minisci (semilunar cartilages) of the tibia
   Medial & lateral condyles of femur
   Anterior cruciate ligament –                           Femur
 attaches to the anterior intercondylar tubercle of the tibia;
 passes posteriorly, laterally, and upward to attach to the femur
 on the medial side of the lateral condyle
                                                       Lateral condyle                   Medial condyle


                                                                                                           Anterior cruciate

2. Humeroulnar (Elbow) – close gripping of the trochlea by the ulna’s trochlear notch that forms the hinge
   a) Olecranon process of the ulna
                                                                                  Olecranon process
   b) Trochlea of the humerus
                    Radius                                                                          Trochlear notch

                   Ulna                                                                          Ulna

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Ball-and-socket – ball shaped head of one bone fits into a cuplike depression of another; allows movement in
all directions and pivotal rotation

1. Coxal Joint (Hip) – formed by the articulation of the spherical head of the femur with the deeply cupped
acetabulum of the Os Coxae (hip bone)
                a) Acetabulum of os coxae
                b) Head of femur
                                                                                               Os coxa



2. Glenohumeral Joint (Shoulder) – large hemispherical head of humerus fits in the shallow glenoid fossa of
the scapula like a golf ball sitting on a tee
                 a. Glenoid fossa of scapula
                 b. Head of humerus


                                                                                      Glenoid fossa

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