Anatomy and Function of the Glenohumeral Joint

SHOULDER JOINT (GLENOHUMERAL)

Shallow glenoid fossa deepened by glenoid labrum Synovial, Ball and socket Humeral head is 1/3 hemisphere Capsule: Strong & taut superiorly (anti-sag), inferiorly lax and inserted lower to allow wide abduction, flexion and extension Synovium: Envelops biceps tendon, communicates with bursae anteriorly and posteriorly LIGAMENTS: Anterior Opening of subscapular bursa 4: Subscapularis 5: Teres major 6: Supraspinatus 7: Short head biceps 8: Pectoralis minor 12 13 Axillary nerve Blood: circumflex humerals Nerves: Subscapular, suprascapular, axillary (Hilton's law) Bursae: Subscapular, subacromial, infraspinatus, supraspinatus Stability: Bones (poor), Capsule (relatively poor), Muscles +++ ligaments +++ Support: Rotator cuff (subscapularis, supraspinatus, infraspinatus, teres minor), long head biceps, triceps in abduction, muscles from chest to arm