Video Gallery

Avoiding Femoral Tunnel Convergence During Single-Bundle Anterior Cruciate Ligament and Fibular Collateral Ligament Reconstruction

March 01, 2019

Contributors: Jorge Chahla Jr, MD; Alexander S. Kuczmarski, MSc; Robert F LaPrade, MD, PhD; BURU GILBERT MOATSHE; Mitchell Iung Kennedy, BS; Mitchell Iung Kennedy, BS

Tunnel convergence may occur on failure to adapt isolated knee ligament reconstruction techniques to account for the multiple tunnels used for multiligament reconstruction. Tunnel integrity is maintained with a bone bridge of at least 2 mm present between tunnels. Tunnel convergence can result in graft damage or reduced ability to fix grafts because of limited bone mass, which may lead to reconstruction failure. Tunnel convergence in the distal femur is guaranteed to occur during single-bundle anatomic anterior cruciate ligament (ACL) and fibular collateral ligament (FCL) reconstruction if the FCL femoral tunnel is drilled at 0° in the axial and coronal planes (the manner in which it is done during isolated FCL reconstruction). This video demonstrates the technique for correctly orienting femoral tunnels in three dimensions to avoid tunnel convergence during single-bundle anatomic ACL and FCL reconstruction. The risk of tunnel convergence between the ACL and FCL femoral tunnels is eliminated if the FCL femoral tunnel is oriented 35° to 40° anterior in the axial plane. A randomized controlled trial followed 36 patients with an FCL tear, 31 of whom also had an ACL tear, for 6 months after reconstruction. At 6 months postoperatively, varus stress radiographs revealed considerably decreased lateral compartment gapping in the reconstruction group compared with the control (nonsurgical) group. A retrospective case series followed 43 patients with an FCL tear, 31 of whom also had an ACL tear, for 2 years after reconstruction. Considerable improvements in all patient-reported outcomes were observed 2 years postoperatively, with no differences reported between the isolated FCL reconstruction group and combined FCL-ACL reconstruction group. In any complex knee reconstruction procedure, preoperative planning and intraoperative verification of tunnel orientation in three dimensions are essential to clinical success. The modification of tunnel orientations used for isolated knee ligament reconstruction prevents tunnel convergence during multiligament reconstruction without negatively affecting clinical outcomes.