[Trauma and degeneration of the acromioclavicular joint].

Osteoarthritis or instability of the acromioclavicular (AC) joint may cause significant impairment or pain in the shoulder. If symptoms of osteoarthritis persist despite conservative treatment, distal clavicular resection is usually curative. Injuries and instability are classified according to Rockwood. Treatment of mild instability due to trauma is nonoperative. An underestimated acute injury to the AC joint may result in chronic instability. Different techniques are presented for operative treatment of significant acute or chronic instability. Arthroscopic methods are now available for treating both acute and chronic instability.