Evaluation of a behind-remnant approach for femoral tunnel creation in remnant-preserving double-bundle anterior cruciate ligament reconstruction — Comparison with a standard approach

• Two approaches in remnant-preserving double-bundle ACL reconstruction were compared.
• A behind-remnant approach can be achieved without any removal of the remnant tissue.
• The behind-remnant approach can create femoral tunnels with high reproducibility.
• The behind-remnant approach shows equivalent tension curves between the bundles.

PurposeTo evaluate a novel approach for femoral tunnel creation, a behind-remnant approach, in remnant-preserving double-bundle anterior cruciate ligament (ACL) reconstruction through comparison with a standard approach.MethodsSixty patients who underwent remnant-preserving double-bundle ACL reconstruction were included. Thirty patients with a standard approach were classified as the standard group, and 30 patients with a behind-remnant approach as the behind-remnant (BR) group. The anteromedial bundle (AMB) and posterolateral bundle (PLB) were provisionally fixed at 20° and 45° of flexion to a graft tensioning system during surgery. Bundle tension was recorded during knee flexion–extension and in response to anterior or rotatory loads. Femoral tunnel positions were then assessed using the quadrant method.ResultsDuring flexion–extension, the BR group showed equivalent tension curves between AMB and PLB, while the standard group showed reciprocal tension curves. The tension on the PLB was lower than the AMB in response to anterior or rotatory loads in the BR group, while the AMB and PLB shared equivalent loads in the standard group. Tunnel position of the AMB in the BR group was lower and deeper, with smaller variances, than that in the standard group. Tunnel position of the PLB in the BR group was lower than that in the standard group.ConclusionsIn remnant-preserving double-bundle ACL reconstruction, a behind-remnant approach can be achieved without any removal of the remnant tissue, and could create a deeper and lower AMB tunnel and a lower PLB tunnel with higher reproducibility, showing equivalent tension curves between the AMB and PLB.