Selection of Interferential Screw for Fixation of Graft in Tibial Tunnel during Anterior Cruciate Ligament Reconstruction by Novel Probe Test

J Orthop Case Rep. 2024 Jul;14(7):172-178. doi: 10.13107/jocr.2024.v14.i07.4618.

Abstract

Introduction: Anterior cruciate ligament (ACL) reconstruction is a common orthopedic procedure, employing various grafts such as the hamstring tendon, bone-patellar bone, and quadriceps tendon. Fixation methods include suspensory loop with button, interferential screw, and cortical fixation. The optimal screw diameter for tibial tunnel fixation remains undefined, with choices ranging from 1mm smaller to 1-2 mm larger than the tunnel diameter. Screw-related complications such as breakage and thread flattening are concerns. This study was to determine the ideal screw diameter for secure graft fixation in the tibial tunnel during ACL reconstruction.

Materials and methods: A novel arthroscopic probe technique was utilized to assess tibial tunnel bone integrity. Bone quality was categorized into weak, strong, and very strong. Screw size selection, either equal to or 1-2 mm larger than the tunnel diameter, was based on bone quality. Screw lengths varied from 25 mm to 35 mm.

Results: The novel technique significantly reduced screw-related complications, from 9.6% (24 out of 248 patients) to 0.5% (l out of 187 patients). The need for additional cortical stabilization decreased from 14.5% (36 out of248 patients) to 1.6% (3 out of 187 patients).

Conclusion: The low-cost, efficient 2-min probe test is a secure and effective method for selecting interferential screws in ACL reconstruction, minimizing complications, and additional stabilization needs.

Keywords: Anterior cruciate ligament; biodegradable screw; graft fixation; tibial tunnel.