Femoral Interference Screw Divergence in Arthroscopically Assisted Anterior Cruciate Ligament Reconstrucitons

Abstract

Femoral interference screw and graft divergence was analyzed in fifty-six consecutive arthroscopically assisted anterior cruciate ligament reconstructions using autologous bone-patellar tendon-bone grafts performed between January 1992 and May 1993. A double incision technique was used in 20 cases and a single incision technique with endoscopic fixation was utilized in 36 cases. All grafts were fixed with interference screws. No screw-graft divergence was seen on the tibial side. In antero-posterior radiographs 5 patients in the double incision group and 6 patients in the single incision group had a screw-graft divergence on the femoral side. In lateral radiographs, the 8 cases in the double incision and 6 cases in the single incision group exhibited a serew-graft divergence. The differences between two groups were not statistically significant in both antero-posterior and lateral radiographs. All divergence angles were below the critical failure limit of 30 degrees, previously demonstrated in biomechanical studies. The early post-operative rehabilitation was quicker in the single incision group, but no difference was seen at the end of the 6th week in terms of range of motion and knee stability between two groups. No correlation was observed between screw divergence and clinical knee stability. It was concluded that, given the lower morbidity and cosmetic advantage of the single incision technique, it should be prefered in the reconstruction of the anterior cruciate ligament.