ACL reconstruction: comparison between transtibial and anteromedial portal techniques

Purpose: The purpose of this study was to compare the transtibial reconstruction technique of the anterior cruciate ligament (ACL) with the anteromedial (AM) portal technique in their ability to place the femoral and tibial tunnels within the ACL footprints. Methods: Forty patients were sequentially enrolled in two different surgical techniques, 20 patients in the transtibial and 20 patients in the AM portal technique. All patients underwent computed tomography scan of the operated knee. The center of the femoral tunnel aperture on the lateral femoral condyle was measured according to the quadrant method. On the tibial side, the center of the tibial tunnel was measured in the sagittal plane. These measurements were compared with the center of the normal AM and PL bundles. Results: There were no differences in the center of the femoral tunnels on the Blumensaat's line between the two groups (mean 23.5% (4.2) for the transtibial technique and 26.0% (4.3) for the AM portal technique (P = n.s.). In the height of the femoral condyle, the center of the tunnels was significantly lower in the AM portal technique group [mean 34.7% (3.8) vs. 24.0% (7.9) (P < 0.001)]. In the tibia, the center of the tunnel in the sagittal plane was significantly posterior in the transtibial technique (mean 55.4% (4.9) vs. 44.4% (3.7) (P < 0.001). Conclusions: The AM portal technique places the femoral and tibial tunnels more centrally in the ACL footprint when compared with the transtibial technique. Level of evidence: II.