Shoulder Anatomy

The following five key features make up the shoulder, providing its structure and allowing it to move freely.

 

Bones

Three bones make up the shoulder: the clavicle, the scapula and the humerus. These bones allow the shoulder to have the large range of movement it does, which is vital to most sports activities.

 

Ligaments

The shoulder joint is reinforced with three ligaments known as the glenohumeral ligaments (superior, medial, and inferior), the coracohumeral ligament, which extends from the coracoid process of the scapula to the greater tubercle of the humerus, and the transverse humeral ligament, which extends from the greater tubercle to the lesser tubercle of the humerus.

 

Joints

Three joints make up the shoulder girdle. These are the glenohumeral, acromioclavicular and the sternoclavicular joints.

 

Cartilage

The shoulder socket is contained in the glenoid labrum, which is a fibrocatrilaginous structure that is attached around the glenoid fossa cavity in the shoulder. This cavity is quite shallow and small, covering only a third of the head of the humerus bone. The glenoid labrum helps deepen the socket.

 

Tendons

The rotator cuff is the group of muscles and their tendons that stabilize the shoulder. These tendons and muscles (supraspinatus, infraspinatus, teres minor and subscapularis) hold the head of the humerus into the glenoid fossa (the shoulder socket).