Radiographic analysis of femoral interference screw placement during ACL reconstruction: endoscopic versus open technique.

Fifty patients with anterior cruciate ligament reconstruction using a bone-patellar tendon-bone autograft performed by two techniques were evaluated roentgenographically to compare the position of the femoral interference screws. Group I consisted of 25 patients in whom the screw was placed using a distal lateral femoral incision (the two-incision technique). Group II patients underwent arthroscopically assisted intraarticular placement of the screw. These patients were then evaluated with anterior-posterior (AP) and lateral roentgenograms. We observed that the AP and lateral screw angles were significantly different with the two techniques. In addition, the endoscopic placement of the femoral screw had an associated divergence of the screw relative to the bone plug in nine of 25 patients compared with zero of 25 in the open group. In conclusion, radiographic differences do exist between femoral interference screws placed for fixation of an ACL graft using the open approach and those placed endoscopically. Although the clinical significance of these differences is not known, we raise the question of greater divergence in femoral interference screw placement with the newer intraarticular femoral interference screw placement techniques.