Accuracy and Reproducibility of the Femoral Tunnel With Different Viewing Techniques in the ACL Reconstruction.

The purpose of this study was to compare the accuracy and reproducibility of the femoral tunnel location among 3 different viewing techniques used during outside-in anterior cruciate ligament (ACL) reconstruction with 3- dimensional (3-D) computed tomography (CT): (1) an anterolateral (AL) or anteromedial (AM) portal with a 30° arthroscope (A group) vs (2) a posterolateral (PL) portal with a 70° arthroscope (PL group) vs (3) a trans-septal (TS) portal with a 30° arthroscope (TS group). A total of 106 patients undergoing outside-in ACL reconstruction were recruited. Patients were divided into 3 groups according to viewing technique (A group=36 patients; PL group=35 patients; TS group=35 patients). Femoral tunnel locations were evaluated with the quadrant method and the anatomic coordinate axes measurement (ACAM) method in the medial wall of the lateral femoral condyle using 3-D reconstructed CT. The accuracy and reproducibility of the femoral tunnel locations were compared among the 3 techniques. The accuracy of the tunnel location was higher in the TS group by the quadrant method as well as the ACAM method. The reproducibility of the femoral tunnel position in the TS group was the highest, and the femoral tunnel locations of the TS group were more compactly distributed compared with those of the A and PL groups. The accuracy and reproducibility of the femoral tunnel location could be improved with a TS portal viewed using a 30° arthroscope. Anteromedial/anterolateral and PL portals viewed using a 70° arthroscope showed no difference. [Orthopedics. 2016; 39(6):e1085-e1091.].