ACL reconstruction: correlation of the functional outcome with the position of femoral and tibial tunnels

Introduction The anterior cruciate ligament (ACL) is the main ligament that stabilizes the knee and stops anterior translation. It is also essential to the screw-home mechanism and helps resist valgus and rotational stress. For ACL reconstruction, autograft arthroscopic single-bundle surgery is regarded as the "gold standard" procedure. Joint laxity is enhanced and cartilage degradation is avoided with anatomical ACL restoration. Negative results are frequently caused by technical surgical errors, such as improper tunnel placement.

This study aims to evaluate the functional outcome in ACL-reconstructed patients when a graft is placed in an anatomical position, as well as to compare it with when a graft is placed in a non-anatomical place.

Methodology This is a 24-month prospective observational study conducted on 44 patients who underwent arthroscopic ACL reconstruction, with post-op CT scans performed after permission from the institutional review board (IRB). The most common mode of injury was sports-related. Thirty patients belonged to the  anatomical group, and 14 patients belonged to the non-anatomical group based on inclusion and exclusion criteria. The Lysholm scoring system was used for functional evaluation on follow-up at three, six, and 12 months.

Results The mean Lysholm score was 41.24 before surgery for the entire sample. In the anatomical group, the score improved to 80.91 at three months, 85.91 at six months, and 89.23 at twelve months. In the non‑anatomical group, the score was 58.58 at three months, 65.13 at six months, and 58.58 at twelve months. The improvement in Lysholm scores in the anatomical group was statistically significant.

Conclusion This study concludes that the functional outcome of ACL reconstruction is better when the graft is placed in anatomical footprints than when it is placed in non-anatomical footprints.

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