Shoulder joint Shoulder

cross-section of shoulder joint

the shoulder joint (also known glenohumeral joint) main joint of shoulder. ball , socket joint allows arm rotate in circular fashion or hinge out , away body. formed articulation between head of humerus , lateral scapula (specifically-the glenoid cavity of scapula). ball of joint rounded, medial anterior surface of humerus , socket formed glenoid cavity, dish-shaped portion of lateral scapula. shallowness of cavity , relatively loose connections between shoulder , rest of body allows arm have tremendous mobility, @ expense of being easier dislocate other joints in body. there approximately 4-to-1 disproportion in size between large head of humerus , shallow glenoid cavity.the glenoid cavity made deeper addition of fibrocartilaginous ring of glenoid labrum.

the capsule soft tissue envelope encircles glenohumeral joint , attaches scapula, humerus, , head of biceps. lined thin, smooth synovial membrane. capsule strengthened coracohumeral ligament attaches coracoid process of scapula greater tubercle of humerus. there 3 other ligaments attaching lesser tubercle of humerus lateral scapula , collectively called glenohumeral ligaments.

the transverse humeral ligament, passes lesser tubercle greater tubercle of humerus, covers intertubercular groove, in long head of biceps brachii travels.