Avoiding tunnel collisions between fibular collateral ligament and ACL posterolateral bundle reconstruction

Area of Science:

• Orthopedic surgery
• Biomechanics
• Anatomy

Background:

• Combined anterior cruciate ligament (ACL) reconstruction with fibular collateral ligament (FCL) repair presents challenges.
• Tunnel placement is critical to avoid collisions between the FCL and posterolateral bundle anterior cruciate ligament (PLB-ACL) tunnels.

Purpose of the Study:

• To evaluate the risk of tunnel collisions between FCL and PLB-ACL tunnels during combined ACL reconstruction.
• To identify optimal tunnel positioning to prevent intraoperative complications.

Main Methods:

• Thirty-six synthetic femurs were used to ream FCL and PLB-ACL tunnels.
• Tunnels were evaluated for collisions using radiographic and Multidetector CT imaging after filling non-collided tunnels with epoxy resin.

Main Results:

• Tunnel collision rates were 75% at 30mm depth and 69.4% at 25mm depth for the FCL tunnel.
• Proximal reaming of the FCL tunnel with coronal angulations of 20° and 40° significantly increased collision risk.
• No collisions occurred when the FCL tunnel was reamed parallel to the distal condylar line with axial angulations of 20° and 40°.

Conclusions:

• A concomitant FCL injury is not a contraindication for double-bundle ACL reconstruction.
• Optimal FCL tunnel reaming involves no proximal angulation and anterior direction with axial angulation between 20° and 40°.
• This technique minimizes the risk of tunnel collisions, ensuring successful combined reconstruction.