Comparison of Clinical Results of Anteromedial and Transtibial Femoral Tunnel Drilling in ACL Reconstruction

Abstract Background: This study compares long term results of two femoral bone tunnels in anterior cruciate ligament (ACL) reconstruction. The femoral tunnel can be drilled transtibially (TT) or through an anteromedial portal (AM). Methods: 300 patients with ACL reconstructions were chosen for this study. They were divided into two groups: 150 patients with anteromedial drilling (AM) and 150 with transtibial (TT) drilling. In the AM group the reconstructions were performed using semitendinosus graft with Tape Locking Screw (TLS™) technique (n=87) or Retrobutton™ femoral and BioScrew™ tibial fixation with a semitendinosus-gracilis graft (n=63). In the TT group the fixation method used was Rigidfix™ femoral and Intrafix tibial fixation. The evaluation methods were clinical examination, knee scores (Lysholm, Tegner, IKDC) and instrumented laxity measurements (KT-2000™). Our aim was to evaluate if there is a better rotational stability and therefore better clinical results when using AM drilling. Results: In the AM group there were 18 and in the TT group 17 revision procedures which were excluded from the study, leaving 132 patients in the AM group and 133 in the TT group for evaluation. In the one year follow-up there were 90 patients (68,2 %) in the AM group and 86 patients (64,7 %) in the TT group. In the two year follow-up there were 60 (45,5 %) and 58 (43,6 %) patients, respectively. The Tegner activity level was consistently higher in the TT group from preoperatively to two year follow-up postoperatively (p < 0.05). The IKDC score was better at two year follow-up in the TT group (p < 0.05). Statistical analysis was done using the BMDP Statistical Package (Statistical Solutions Ltd, Cork, Ireland). Conclusion: There was a statistically significant difference in IKDC score at two year follow-up, in favor of the TT drilling group compared with the AM group (p < 0.05). No other differences were found between these groups. Both drilling techniques resulted in improved patient performance and patient satisfaction. Also, we found no data supporting the hypothesis that AM drilling technique provides better rotational stability to the knee. Trial registration: ISRCTN16407730 Keywords: Anterior cruciate ligament reconstruction; clinical outcome; anteromedial; transtibial