O1076 ANTEROMEDIAL VS. TRANSTIBIAL TECHNIQUE FOR CORRECT FEMORAL TUNNEL PLACEMENT DURING ARTHROSCOPIC ACL RECONSTRUCTION WITH HAMSTRINGS: AN IN VIVO STUDY

Abstract

Aim: To evaluate whether a guiding pin for a femoral tunnel could be positioned through the tibial tunnel into the center of the anatomical ACL attachment. Methods: 77 knees underwented arthroscopic ACL reconstruction with hamstrings. The femoral tunnel was drilled through an anteromedial portal at the center of the anatomic insertion at about 10.00 resp.14.00 position. Tibial tunnel (mean diameter 7.55 ± 0.54 mm) was drilled using a guide inserted at 90 degrees of knee flexion. Then, through the tibial tunnel, a 4mm offset femoral drill guide was positioned as close as possible to the femoral tunnel and a 2.5 mm guide wire was drilled. The position of the guide wire was photographed arthroscopically and the deviation was measured as the distance between the center of the femoral tunnel and the guide wire. Results: The mean deviation was 4.50 ± 1.54 mm (p = 0.00000004) In 74 knees (96.1%) the guidewire did not reach the femoral tunnel. Only in 3 knees it reached the superomedial edge of the femoral tunnel. No statistical relationship was found between deviation and tibial tunnel inclination angles or tibial tunnel diameter. Conclusions: Transtibial femoral tunnel drilling does not reach the anatomic site of the ACL insertion, even with larger tibial tunnels (for hamstring grafts up to 8.5 mm). Transtibial tunnel drilling should be replaced by drilling through the anteromedial portal at least for tunnels with diameters < 9 mm.