The scapula, or shoulder blade, is a flat, triangular-shaped bone, that is located posteriorly in the upper thoracic region.
The scapula articulates with the humerus at the glenohumeral joint (or shoulder joint), and with the clavicle through the acromioclavicular joint. Its role is to provide support to the upper extremities, and to enable movements such as protraction and retraction, elevation and depression, and upward and downward rotation.