Accuracy of positioning of tibial tunnel in Anterior Cruciate Ligament reconstruction using multiple intra-operative landmarks

Background: Anterior cruciate ligament reconstruction (ACLR) aims to restore knee stability and function by accurately positioning the tibial tunnel. Previous studies have indicated variability in tibial tunnel placement, often based on data from Western populations. This study aims to evaluate the accuracy of post-operative radiographs in replicating intraoperative tibial tunnel positions based on anatomical landmarks specific to the Indian population.

Methods: This prospective observational cross-sectional study was conducted over 18 months, involving 74 patients (18-40 years old) undergoing single-bundle anatomical ACLR. The surgeries were performed by six experienced surgeons at RG Kar Medical College, Kolkata. Post-operative anteroposterior (AP) and lateral (Lat) radiographs were used to assess the coronal and sagittal positions and angles of the tibial tunnels. The positions were calculated as percentages from specific anatomical landmarks, with coronal and sagittal tunnel angles measured accordingly.

Results: The study analyzed mean values and statistical tests for tunnel positions and angles. Significant differences were observed among different anatomical landmarks. The ACL footprint and the posterior border of the anterior horn of the lateral meniscus (PBoAHoLM) were the most accurate for coronal plane tunnel positioning (Z = 7.98). For sagittal alignment, PBoAHoLM was the most reliable (Z = 7.24). The study highlighted that native footprints and specific landmarks effectively replicated tibial tunnel angles in both planes.

Conclusion: Tibial tunnel position was most accurately reproduced when surgeons used both Footprint of ACL & Posterior border of ARLM as landmarks. As a single landmark, the surgeons operating with the footprint of ACL produced the most accurate Tibial Tunnel. Shaving off the remnant footprint of ACL is not necessary to create the ideal tibial tunnel position