Humeri: Articulatio

: The shallow, pear-shaped socket on the lateral angle of the scapula (shoulder blade).

: A fibrocartilaginous rim that attaches to the margin of the glenoid cavity , deepening the socket to provide extra stability . Ligaments and Support articulatio humeri

The joint is reinforced by several key ligaments and a fibrous capsule: Anatomy, Shoulder and Upper Limb, Glenohumeral Joint - NCBI : The shallow, pear-shaped socket on the lateral