The Shoulder

The shoulder joint, as it is commonly called, is not a single joint but a complex arrangement of bones, ligaments, and musculotendinous units that is more aptly called the shoulder girdle. The primary role of the shoulder girdle is to provide a tremendous range of motion for positioning the upper extremity in space. The shoulder girdle also provides power and support for the upper extremity throughout and at the extremes of the range of motion. Many shoulder girdle problems stem from overuse injuries such as pitching a baseball or serving a tennis ball that exploit both the power and range of motion of the shoulder girdle. This chapter will review the anatomy of the shoulder girdle and provide an approach to evaluating and treating common shoulder problems.