A cadaveric study examining acromioclavicular joint congruity after different methods of coracoclavicular loop repair.

A basic principle in the treatment of joint injuries is to restore congruity with the hope that restoration may lessen the incidence of late arthritis. The acromioclavicular (AC) joint is frequently injured. Many AC joint injuries are treated nonoperatively; others are treated surgically. Coracoclavicular loop repair of the AC joint is believed to lead to anterior displacement of the clavicle relative to the acromion. This cadaveric study evaluated the effectiveness of three techniques of coracoclavicular loop repair in restoring AC joint congruity through measurement of anterior displacement. Fourteen shoulders were repaired by the three different techniques, all of which consisted of fixation through a drill hole in the clavicle and around the crook of the coracoid with a suture. The techniques only varied by the placement of the drill hole in the clavicle (ie, either posterior, middle, or anterior). The results of this study indicate that as the drill hole moved anteriorly on the clavicle, joint congruity was more closely approached and less anterior displacement of the clavicle occurred. However, none of the methods of coracoclavicular loop fixation restored full AC joint congruity.