A new behind-remnant approach for remnant-preserving double-bundle anterior cruciate ligament reconstruction compared with a standard approach

To introduce a new behind-remnant approach for double-bundle (DB) anterior cruciate ligament (ACL) reconstruction and to compare the femoral tunnel positions of anteromedial (AM) and posterolateral (PL) bundles between the new and standard procedures by a three-dimensional computed tomography (3D-CT). During DB ACL reconstruction, two approaches for femoral tunnel creation were consecutively practiced from 2010 to 2012. The patients were evaluated retrospectively as a cohort study. A total of 200 primary ACL reconstructions have been performed using a transtibial approach. One approach was a standard approach from the front in which the ACL remnant was peeled off from the attachment, and two guide wires were inserted based on anatomic bony landmarks (standard group). The other approach was a new behind-remnant approach in which the ACL remnant was kept untouched and two guide wires were inserted at the posterior margin of the direct ACL insertion (behind-remnant group). The position of the AM and PL femoral tunnels was expressed on a 3D-CT reconstructive image using the quadrant method with a statistical analysis. The depth of the AM center was 24 +/- A 6 % (mean and standard deviation) in the standard group and 22 +/- A 5 % in the behind-remnant group. The height of the AM tunnel center was 22 +/- A 8 % in the standard group and 31 +/- A 8 % in the behind-remnant group. The depth of the PL tunnel center was 32 +/- A 6 % in the standard group and 35 +/- A 5 % in the behind-remnant group. The height of the PL tunnel center was 47 +/- A 9 % in the standard group and 55 +/- A 7 % in the behind-remnant group. The AM and PL femoral tunnels in both groups were created within the normal anatomic footprint of the previous studies. The behind-remnant approach created a significantly lower femoral tunnel for both AM (p = 0.000) and PL tunnels (p = 0.000). The depth of both AM and PL tunnels was not significantly different between the two groups (n.s.). The new behind-remnant procedure is technically simple and reproducible as a remnant-preserving ACL reconstruction. Cohort study, Level III.