The glenoid cavity or glenoid fossa of scapula is a part of the shoulder. It is a shallow, pyriform articular surface, which is located on the lateral angle of the scapula. It is directed laterally and forward and articulates with the head of the humerus (a long bone in the arm that runs from the shoulder to the elbow); it is broader below than above and its vertical diameter is the longest.

This cavity forms the glenohumeral joint along with the humerus. This type of joint is classified as a synovial, ball and socket joint. The humerus is held in place within the glenoid cavity by means of the long head of the biceps tendon. This tendon originates on the superior margin of the glenoid cavity and loops over the shoulder, bracing humerus against the cavity. The rotator cuff also reinforces this joint more specifically with the supraspinatus tendon to hold the head of the humerus in the glenoid cavity.

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