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The Shoulder Joint TEST MONDAY. Anterior Shoulder Muscles. Coracobrachialis Pectoralis Major Subscapularis Biceps Brachii. Biceps Brachii. Origin Short head: coracoid process of scapula Long head: supraglenoid tubercle of scapula Insertion Tuberosity of radius
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Anterior Shoulder Muscles • Coracobrachialis • Pectoralis Major • Subscapularis • Biceps Brachii
Biceps Brachii • Origin • Short head: coracoid process of scapulaLong head: supraglenoid tubercle of scapula • Insertion Tuberosity of radius • Action Flexion of the elbow and shoulder, Supinates forearm • ***the long head is the “5th rotator cuff”
Coracobrachialis • O: Coracoid process • I: Anteromedial surface of midshaft of humerus • Actions: (WEAK!) • Flexion • Adduction of the shoulder
Pectoralis Major • Origin: • Medial two-thirds of clavicle • Sternum • Insertion: intertubercular groove • Actions • Upper fibers (Clavicular) • Flexion • Horizontal Adduction • Lower fibers (Sternal) • Internal/medial Rotation • Horizontal adduction
Subscapularis • O: Subscapular fossa • I: Lesser tubercle and crest of humerus • Actions: • Internal Rotation • Stabilization • Anterior Rotator Cuff Muscle.
Superior Shoulder Muscles • Deltoid • Supraspinatus
Deltoid • Origin • Lateral 1/3 of clavicle (Anterior fibers) • Acromion process (Middle fibers) • Spine of scapula (Posterior fibers) • Insertion – deltoid tuberosity • Actions • Anterior –Flexion • Middle – Abduction • Posterior –Extension
Supraspinatus • O: Supraspinous fossa • I: Greater tubercle • Action: • Abduction • Stabilization • Superior Rotator Cuff Muscle. • Most injured rotator cuff muscle
Inferior Shoulder Muscles • Latissimus Dorsi • Teres Major
Latissimus Dorsi • O: Spinous process of lower 6 thorasic and all lumbar and sacral vertebrae; iliac crest • I: Intertubercular groove • Actions: • Adduction • Internal Rotation
Teres Major • O: Inferior angle of scapula • I: Intertubercular groove • Actions: • Adduction • Internal rotation • “Lats little helper”
Posterior Shoulder Muscles • Infraspinatus • Teres Minor • Triceps Brachii
Triceps Brachii • Origin Long head: infraglenoid tubercle of scapulaLateral head: posterior surface of humerus, Medial head: posterior surface of humerus, Insertion Olecranon process of ulna • Action Chief extensor of elbow (long head extends the shoulder)
Infraspinatus • O: Infraspinous fossa • I: Greater tubercle • Actions: • External rotation • Stabilization • Posterior Rotator Cuff Muscle • Second most commonly injured rotator cuff muscle
Teres Minor • O: lateral border of scapula • I: Greater tubercle • Actions: • External rotation • Stabilization • Posterior Rotator Cuff Muscle
Trapezius • Origin occipital bone, nuchal ligament, and spinous processes of C7 - T12 vertebrae • Insertion Lateral third of clavicle, acromion, and spine of scapula • Action • superior fibers elevate, • middle fibers retract, • inferior fibers depress scapula;
Levator Scapula • Origin C1 - C4 vertebrae • Insertion Superior angle • Action Elevates scapula
Rhomboid major and minor • Origin Minor: spinous processes of C7 and T1 vertebraeMajor: spinous processes of T2 - T5 vertebrae • Insertion Medial border of scapula • Action Retract scapula
Serratus Anterior • Origin the eight upper frontal ribs • Insertion lateral border of scapula • Action protracts scapula
Name the muscle. Coracobrachialis Name the action Flexion and Adduction of the shoulder
Name the muscle. Pectoralis Major Function Horizontal Adduction Internal roatation
Name the muscle. Subscapularis Name the action Internal rotation of the shoulder
Name the muscle. Deltoid Name the action Abduction of shoulder (middle third) Flexion (anterior deltoid) Extension (posterior deltoid)
Name the muscle. Infraspinatus Name the action External rotation