Skuldergirdel

Skuldergirdel, or the shoulder girdle, is the set of bones and joints that connects the upper limb to the axial skeleton and enables the wide range of shoulder movement. It consists of two bones on each side: the clavicle (collarbone) and the scapula (shoulder blade). The clavicle is an S-shaped bone that runs horizontally across the upper chest. Medially it articulates with the manubrium of the sternum at the sternoclavicular joint, and laterally it meets the acromion of the scapula at the acromioclavicular joint. The scapula is a flat, triangular bone on the posterior thorax with prominent landmarks including the spine, the acromion, the coracoid process, and the glenoid cavity, which forms the shoulder socket with the humerus.

Key joints are the sternoclavicular joint, which attaches the clavicle to the sternum; the acromioclavicular joint, which connects clavicle to the scapula; and the glenohumeral joint, formed by the glenoid cavity and the head of the humerus. The scapulothoracic articulation, while not a true synovial joint, permits the coordinated movement of the scapula on the thoracic wall.

The girdle serves as the anchor for muscles that move the arm and shoulder, transfers load between the upper limb and trunk, and enables motions such as elevation, depression, protraction, retraction, and rotation.

Clinically, injuries include clavicular fractures, acromioclavicular joint separations, and glenohumeral dislocations or subluxations. Variations in size and shape of the clavicle and scapula are common but usually functionally insignificant.