This exhibit depicts the anterior anatomy of the shoulder with inferior acromial spurring and subsequent acromioplasty. Anatomical structures include: the clavicle, acromion, subacromial bursa, supraspinatus, biceps brachii, coracoid process, and the humerus. During abduction, the supraspinatus contracts to raise the arm, and the subacromial bursa glides beneath the acromioclavicular joint to prevent friction. Degenerative bone spurs on the inferior acromion cause narrowing of the subacromial space. The increased friction pinches the subacromial tissues resulting in inflammation, pain, and weakness of the shoulder joint. Decompression is accomplished by smoothing the acromion into a type one (flat) configuration.