Abstract

In the present study, we aimed to determine the risk factors predicting femoral and/or tibial tunnel widening after single-bundle anatomical anterior cruciate ligament reconstruction using hamstring autograft and to investigate the effect of tunnel widening on clinical outcomes. Forty-two patients who underwent single-bundle anterior cruciate ligament reconstruction using hamstring autograft between the dates of November 2011 and June 2020 and met the inclusion criteria of the study were retrospectively reviewed. The amount of tunnel widening was obtained by finding the difference between the measurements made by examining the oblique-coronal and oblique-sagittal reconstruction sections in the computed tomography taken one year after the surgery and the diameter of the drill bit used in the surgery. The patients were divided into two groups as those with tunnel widening (>0.5 mm) and those without tunnel widening (≤ 0.5 mm). The factors that may cause tunnel widening were evaluated separately. International Knee Documentation Committee (IKDC) subjective knee form and Tegner activity scores were used in the clinical evaluation. According to the multivariate regression analysis performed, lateral posterior tibial slope was seen to be a good predictor of femoral and tibial tunnel widening. In the receiver operating characteristic (ROC) analysis, it was determined that lateral posterior tibial slope, especially above 6°, significantly affected both femoral and tibial tunnel widening after anterior cruciate ligament reconstruction. The present study showed that increased lateral posterior tibial slope was an independent factor predicting tibial and femoral tunnel widening following single-bundle anatomical anterior cruciate ligament reconstruction using hamstring autograft, but these tunnel widenings had no significant effect on clinical outcomes.

Key words: Tunnel widening, lateral posterior tibial slope, anterior cruciate ligament