Popliteofibular ligament reconstruction for posterolateral external rotation instability of the knee

Abstract

The aim of this study was to assess the clinical outcome of popliteofibular ligament (PFL) reconstruction for posterolateral external rotation instability of the knee. PFL reconstruction was performed consecutively in 22 patients with chronic external rotation instability of the knee. The inclusion criterion for surgery was tibial external rotation of 10 degrees more than the contralateral uninjured knee without varus laxity. A double bone tunnel was created at the PFL insertion of the fibular head through the lateral incision of the knee joint and a single bone tunnel at the popliteus tendon insertion on the femoral side. A semitendinosus autograft tendon or tibialis anterior allograft tendon was introduced through the fibular tunnel as a loop, then both free ends of the graft were introduced through the femoral tunnel and a bioabsorbable interference screw was used to fix the graft. The minimum follow-up was 2 years. Clinical review included the International Knee Documentation Committee (IKDC) scale and tibial external rotation assessment. All patients' preoperational tibial external rotation averaged 15 degrees more than the contralateral uninjured knee. operatively the tibial external rotation was decreased, average -3 degrees compared with the contralateral side. This difference was statistically significant. The final IKDC grades were: 22 cases with grade D preoperatively, and 6 were grade A, 8 were grade B, 7 were grade C and 1 was grade D postoperatively. In this small clinical series, PFL reconstruction technique was shown to correct pathological excessive tibial external rotation.