Distal biceps brachii tendon repair. An in vitro biomechanical study of tendon reattachment.

Clinical reports suggest that suture anchors can simplify repair of distal biceps tendon avulsions. In this study, fixation strengths of Mitek and Statak suture anchors were compared with strength of reattachment using transosseous suture tunnels in eight cadaveric radii. Cyclic loading and load-to-failure testing were performed: No specimen failed during testing to 50 N for 3600 cycles: however, four of the Mitek anchors and one of the Statak anchors protruded out of the medullary canal. The mean load to failure of the Mitek suture anchor complexes was 220 +/- 54 N, that of the Statak suture anchor complexes was 187 +/- 64 N, and that of the transosseous sutures was 307 +/- 142 N. There was no significant difference in the failure load or mechanism of failure between the Statak and Mitek anchors. Transosseous sutures failed at significantly greater loads on static testing than the suture anchors. Cyclic loading results suggest that the bony fixation achieved using these three techniques should be sufficient to allow immediate passive mobilization of the elbow after surgery. Protrusion of the suture anchors out of the tuberosity during cyclic loading is a concern because of potential development of a gap at the repair site and interference with forearm rotation.