The ability of 3 different approaches to restore the anatomic anteromedial bundle femoral insertion site during anatomic anterior cruciate ligament reconstruction

Abstract

Purpose: The purpose of this study was to determine whether drilling the femoral tunnel when performing anterior cruciate ligament (ACL) reconstruction through the accessory medial portal, as opposed to drilling the tunnel transtibially, will lead to more frequent location of the anteromedial femoral tunnel within the anatomic anteromedial bundle insertion site.

Methods: Primary anatomic double-bundle reconstruction was performed on 113 patients. Intraoperatively, we placed a guide pin through the anteromedial and posterolateral tibial tunnels and accessory medial portal, attempting to reach the center of the native femoral anteromedial bundle insertion. For each approach, the position of the guide pin was classified as (1) within the center of, (2) off-center within, or (3) outside of the femoral anteromedial insertion.

Results: There were significant differences in the ability of each approach to reach the center of the femoral anteromedial bundle insertion. Through the tibial anteromedial tunnel, the femoral anteromedial insertion center was reached in 4.4% of cases, whereas it was off-center within and outside of the femoral anteromedial insertion in 23.0% and 72.6%, respectively. Through the tibial posterolateral tunnel, the femoral anteromedial insertion center was reached in 60.2% of cases, whereas it was off-center within and outside of the femoral anteromedial insertion in 23.9% and 15.9% of cases, respectively. When approached from the accessory medial portal, the center of the femoral anteromedial insertion was reached in 100% of the cases. Ultimately, the femoral anteromedial tunnel was drilled through the tibial anteromedial tunnel in 0.9%, through the posterolateral tunnel in 62.8%, and through the accessory medial portal in 36.3% of cases.

Conclusions: Drilling the femoral tunnel for the anteromedial graft through the accessory medial portal, as opposed to drilling the tunnel transtibially, leads to more frequent location of the anteromedial femoral tunnel within the anterior cruciate ligament anteromedial bundle anatomic footprint.