Evaluation of an interference screw for tendon reattachment to small bones.

Abstract

To compare the strength of interference screw fixation of the tendon to suture button fixation and staple fixation methods. Biomechanical study. The femurs and flexor digitorum tendon of twelve rabbits were used. The tendon was attached to the medial condyle of the femur using one of the following three surgical procedures: (a) interference screw fixation: tendon-junction screw was used as an interference screw, (b) suture button fixation: the tendon was inserted through a hole and attached with a button on the opposite side, and (c) staple fixation: the tendon was attached using two staples. Strengths of the attached tendons were then measured using a universal testing machine. The ultimate failure load of interference screw fixation was 62.8 +/- 9.0 N, whereas that of suture button fixation was 13.9 +/- 3.8 N and staple fixation was 23.9 +/- 2.6 N. Interference screw fixation provides significant initial fixation strength (p < 0.05).