glenohumeralledet

Glenohumeralledet, or the glenohumeral joint, is the ball-and-socket synovial joint between the glenoid cavity of the scapula and the head of the humerus. The glenoid fossa is shallow, and the articular rim is deepened by the glenoid labrum, a fibrocartilaginous rim that increases stability. The joint is enclosed by a fibrous capsule that attaches to the glenoid margin and the anatomical neck of the humerus, and is reinforced by the glenohumeral ligaments (superior, middle, inferior) as well as the coracohumeral ligament. The coracoacromial arch provides an additional structural roof.

The glenohumeral joint is the most mobile major joint in the body, permitting flexion and extension, abduction and adduction, as well as internal and external rotation and circumduction. Stability is primarily dynamic, provided by the rotator cuff muscles (supraspinatus, infraspinatus, teres minor, subscapularis) and the long head of the biceps, which hold the humeral head centered in the glenoid during motion. The joint relies on a modest passive constraint supplied by the ligaments and the negative intra-articular pressure.

Nerve supply comes from branches of the brachial plexus, especially the axillary nerve (deltoid and teres minor) and the suprascapular nerve (supraspinatus and infraspinatus). Blood supply is from the posterior and anterior humeral circumflex arteries, with contributions from the suprascapular and other branches.

Clinical significance includes dislocation (most often anterior), rotator cuff tears, glenoid labral injuries such as SLAP lesions, osteoarthritis, and adhesive capsulitis. Imaging typically involves radiographs and MRI for soft-tissue assessment. Treatment ranges from conservative management and physical therapy to arthroscopic or open surgical repair and, in severe cases, shoulder arthroplasty.