[Omarthrosis]

Degenerative arthrosis of the shoulder is less commonly diagnosed than at the joints of the lower extremity. The shoulder joint does not bear weight and some of the mechanical stresses are taken up by the subacromial space. However, anatomical studies reveal a significant incidence of degenerative changes at the glenohumeral joint with increasing age. Arthrosis is caused by mechanical loading, rotator cuff defects, and abnormal joint motion following surgery. Clinical symptoms are rarely focused on the glenohumeral joint. Clinical findings are also unspecific. Rotation of the elevated arm with compression of the joint is a reliable sign of arthrosis. The diagnosis is made with anteroposterior and axial radiographs. Ultrasonography should always be performed and computed tomography only in specific cases. Nonoperative treatment includes analgesic and antiphlogistic medication, motion therapy, and muscle exercises. Shoulder arthroplasty is favoured in advanced arthrosis. New prostheses are intended to reconstruct the normal anatomy as closely as possible.