Influence of visualization portal selection on femoral tunnel placement and anterior knee pain after anterior cruciate ligament reconstruction.

Abstract

Accurate femoral tunnel placement is considered important for successful anterior cruciate ligament reconstruction (ACL-R). Visualization portal selection during femoral tunnel preparation may influence postoperative clinical and radiographic outcomes. This retrospective comparative study included 184 patients (mean age: 28.1 ± 6.7 years) who underwent primary ACL-R with ≥24-month follow up. Patients were grouped according to the arthroscopic visualization portal used during femoral tunnel preparation: central transpatellar portal (CTP; n = 90) or anteromedial (AM) portal (n = 94). Femoral tunnel angle, femoral tunnel height ratio, femoral tunnel depth ratio , and tibial tunnel angle were evaluated on postoperative radiographs. Clinical outcomes were assessed using visual analog scale (VAS) and Kujala scores at 3, 6, 12, and 24 months postoperatively. Mean radiographic tunnel parameters did not differ significantly between groups. At 3 months, VAS scores were higher in the CTP group than in the AM group (5.29 ± 1.51 vs. 3.44 ± 1.45; P = 0.001), while Kujala scores were lower (70.64 ± 4.87 vs. 73.00 ± 4.25; P = 0.001). Smaller differences were observed at 6 months, whereas no significant differences were identified at 12 or 24 months. Early postoperative differences remained below previously reported thresholds for clinically meaningful change. Patients undergoing ACL reconstruction with CTP visualization demonstrated higher anterior knee pain-related scores during the early postoperative period compared with those treated using an anteromedial portal. However, these differences were not observed at 12- or 24-month follow up. Mean radiographic tunnel parameters were similar between groups. These findings suggest that AM portal visualization may provide a more favorable early postoperative course while achieving comparable radiographic and mid-term clinical outcomes.