Tunnel widening following anterior cruciate ligament reconstruction using hamstring autograft: a comparison between double cross-pin and suspensory graft fixation

Abstract

Femoral and tibial tunnel widening following ACL reconstruction using hamstring autograft has been described. Greater tunnel widening has been reported with suspensory fixation systems. We hypothesized that greater tunnel widening will be observed in patients whose hamstring autograft was fixated using a cortical, suspensory system, compared to double cross-pin fixation on the femur. We performed clinical and radiographic evaluation on 46 patients at minimum 2 years after primary ACL reconstruction. We measured subjective and objective outcomes including KT-1000 and AP, lateral radiographs. A musculoskeletal radiologist, independent of the surgical team, measured tunnel width, while correcting for magnification, at the widest point and at 1 cm away from tibial and femoral tunnel apertures. Patients in the suspensory graft fixation group exhibited significantly greater absolute change and greater percent change in femoral tunnel diameter compared to patients with double cross-pin fixation (P<or=0.05). This difference was noted on both AP and lateral radiographs and at both measurement sites. There was no significant difference between groups for tibial tunnel widening, IKDC subjective scores or KT-1000 side to side differences. There was significantly more femoral tunnel widening associated with the use of the endobutton suspensory fixation system compared to the use of double cross-pins for fixation within the tunnel.