外側関節外腱結合症を伴うオーバーザトップ ACLR と前内側 ACLR

Anterior cruciate ligament reconstruction (ACLR) is one of the most commonly performed procedures in orthopedic sports medicine, aimed at restoring knee stability, facilitating return to activities, and preventing secondary injuries to the cartilage and menisci. Improved understanding of knee joint anatomy and biomechanics has led to advancements in surgical techniques, and modern 'anatomic' techniques have shown favorable outcomes in most patients. However, despite technical advancements, ACL reconstruction techniques still fail to fully restore normal knee biomechanics, particularly with regard to tibial rotation, leaving some patients with residual instability. Additionally, the rate of return to high-level sports has been reported as low as 63% at two years.

Residual anterolateral subluxation, as measured by the pivot shift test, is a clinical indicator of internal rotation laxity and is associated with poor outcomes and low patient satisfaction. Such altered kinematics may contribute further to the development of osteoarthritis (OA). The inability of traditional ACLR to reliably restore normal tibial rotational kinematics could be one reason for this outcome.

Lateral extra-articular tenodesis (LET) is performed alongside ACLR to control anterolateral rotational instability in knees with ACL deficiency. Recent studies have shown that this procedure reduces the risk of ACL graft re-rupture, better restores knee joint kinematics, and improves return-to-sport rates. ACLR and LET procedures are now routinely performed in many centers.

The over-the-top (OTT) ACL reconstruction technique involves passing the graft over the superomedial edge of the lateral femoral condyle and securing it to the lateral femoral cortex. The proposed advantages of this technique include its safety, ease of use, reproducibility, low cost, and compatibility with all graft types and fixation methods. Additionally, the OTT technique can be used to reinforce ACL remnants, thus minimizing technical challenges encountered during anatomic reconstruction procedures. These challenges include difficulty visualizing the femoral placement, mismatches between tibial and femoral tunnels, reliance on clock-face systems for femoral tunnel positioning, and instrument impingement during excessive knee flexion.

Currently, there is limited literature comparing the outcomes of OTT and anatomic ACLR techniques, and no studies compare the OTT and ACLR + LET procedures.

The aim of this study is to compare the clinical and radiological outcomes, as well as return-to-sport rates, between patients undergoing the Over-the-Top ACL Reconstruction technique and those undergoing the Anteromedial ACL Reconstruction technique with Lateral Extra-Articular Tenodesis.