Arthrometric Stability of Horizontal Versus Vertical Single-bundle Arthroscopic Anterior Cruciate Ligament Reconstruction

The anteroposterior (AP) stability of standard anterior cruciate ligament (ACL) reconstruction, referred to as "vertical," was compared with that of a modified femoral position, referred to as " horizontal," which is lower than and anterior to an operative knee at 90 degrees flexion. Two consecutive series of 50 patients underwent vertical and horizontal arthroscopic single-bundle ACL reconstruction, respectively. For vertical reconstruction, the clock position was chosen, placing the graft at 10:30 in right knees and 1:30 in left knees, 1 to 2 mm anterior to the posterior femoral cortical cortex and at the back of the resident ridge. In the horizontal reconstruction, the transplant replaced the original ligament insertion at approximately the 9:30 o'clock position in right knees and the 2:30 o'clock position in left knees, approximately 2 mm in front of the posterior femoral cortical cortex. One year after surgery, the results of stabilometric evaluation revealed good performance after horizontal transplant. The mean clinical results changed from 1.0 (+/- 1.3) mm for vertical to 0.7 (+/- 1.3) mm for horizontal reconstruction.