Anatomic Posterolateral Corner Reconstruction Using a Fibula Cross-Tunnel Technique: A Cadaveric Biomechanical Study.

Purpose: To compare the biomechanical properties of a fibula cross-tunnel technique for posterolateral corner (PLC) reconstruction with those of intact knees.

Methods: Seven fresh-frozen cadaveric knees were tested while intact, after PLC tear, and after reconstruction. Testing of the parameters listed above was performed at 0°, 30°, 60°, and 90° of knee flexion. Reconstruction was performed using 2 independent tendon autografts. Afterward, the fibula and graft were loaded to failure.

Results: Reconstruction restored external rotation (0°: 11.75° ± 2.02° to 9.81° ± 1.81°, P = .57; 30°: 17.91° ± 1.32° to 13.96° ± 2.84°, P = .12; 60°: 15.86° ± 1.68° to 13.26° ± 3.58°, P = .41; 90°: 15.53° ± 1.62° to 14.07° ± 2.95°, P = .54) to the intact state, and posterior translation (0°: 3.66 ± 0.85 mm to 3.31 ± 0.89 mm, P = .87; 60°: 3.15 ± 0.45 mm to 2.96 ± 0.45 mm, P = .73; 90°: 2.74 ± 0.33 mm to 3.05 ± 0.41 mm, P = .41) and varus angulation (0°: 0.92° ± 0.35° to 1.98° ± 0.42°, P = .55; 30°: 2.65° ± 0.27° to 1.09° ± 0.90°, P = .37; 90°: 4.29° ± 0.44° to 2.53° ± 1.13°, P = .19) under most conditions. During load to failure testing, the construct revealed properties similar to those of native structures (yield load: 330.4 ± 45.8 N; ultimate load: 420.9 ± 37.4 N).

Conclusions: This technique restored external rotation to the intact state after PLC injury in all testing conditions, as well as posterior translation at 0°, 60°, and 90° of flexion, and varus angulation under all conditions tested except 60° of flexion.

Clinical Relevance: Clinically, this surgical technique may eliminate the need for a tibial tunnel for posterolateral corner reconstruction.