CLINICAL ORTHOPAEDICS AND RELATED RESEARCH Number 370, pp. 208-21 1 zyxw 0 2000 Lippincott Williams & Wilkins, Inc. zyx Distal Clavicle Osteolysis Unrelated to Trauma, Overuse, or Metabolic Disease z Bryan J. Hawkins, MD*; D.C. Covey, MD**; and Brent G. Thiel, MDf zyx Osteolysis of the distal clavicle has been re- ported to occur from traumatic, atraumatic (overuse), or systemic causes. Three patients with bilateral osteolysis of the distal clavicles whose osteolysis did not fit these etiologic cate- gories were evaluated. Clinical, imaging, and laboratory evaluations were nonspecific, and histologic sections of the distal clavicle showed evidence of chronic inflammation with reactive change of the articular surface. Patients either had complete resolution or marked improve- ment of their symptoms after bilateral distal clavicle resection at mean followup of zyxwv 5 years 3 months. These cases of osteolysis of the distal clavicle represent a category of this disorder not previously described. (overuse), or systemic causes. Posttraumatic osteolysis can occur as a result of direct trauma to the region of the acromioclavicularjoint.bIn atraumatic osteolysis, injury to the distal clav- icle occurs as a result of repetitive physical ac- tivities, such as weight lifting, which affect the acromioclavicular joint. Systemic causes in- clude hyperparathyroidism, connective tissue disorders, and infection. Reported in this study are three cases of bi- lateral osteolysis of the distal clavicle that do not fit into any of the previously reported eti- ologic categories. Case 1 Osteolysis of the distal clavicle has been described previously. l,*,l0 It has been reported to occur as a result of posttraumatic,atraumatic From zyxwvutsrqp *6565 South Yale, Tulsa OK; **the Department of Orthopaedic Surgery, Naval Hospital, Bremerton, WA; and ithe Department of Orthopaedic Surgery, Medical College of Wisconsin, Milwaukee, WI. Reprint requests to D.C. Covey, MD, Captain, Medical Corps, United States Navy, Department of Orthopaedic Surgery, Naval Hospital, HPOl Boone Road, Bremerton, WA 98312-1898. Received: February 1, 1999. Revised: May 18, 1999. Accepted: June 10, 1999. A 42-year-old Navy yeoman (administrative specialist) presented to the orthopaedic clinic reporting bilateral shoulder pain of many months' duration. The pain initially involved only the left shoulder, but later both shoulders were affected with equal severity. The pain was localized to the acromioclavicularjoints. The patient reported no predisposing history, including trauma, that normally is associated with acromioclavicular disorders. He did not participate in any exercise program and had never been a weight lifter. He also reported no history of systemic arthritic disease and had no other joint symptoms. On physical examination, he had full range of motion (ROM) of both shoulders. There z 208