Shoulder Joint - Glenohumeral Joint

The shoulder joint (or glenohumeral joint from Greek glene, eyeball, + -oid, 'form of', + Latin humerus, shoulder) is structurally classified as a synovial ball and socket joint and functionally as a diarthrosis and multiaxial joint. It involves articulation between the glenoid cavity of the scapula (shoulder blade) and the head of the humerus (upper arm bone).

Due to the very loose joint capsule that gives a limited interface of the humerus and scapula, it is the most mobile joint of the human body.