Combined PCL and PLC reconstruction in chronic posterolateral instability.

PURPOSE: The posterolateral corner (PLC) is more likely to be injured in combination with the posterior cruciate ligament (PCL) or the anterior cruciate ligament than in isolation. This leads to instability of the knee and loss of function. We hypothesised that combined PCL and PLC reconstruction would restore sufficient stability to allow improvement in patient symptoms and function. METHODS: 19 patients who underwent arthroscopic-assisted single-bundle PCL and PLC reconstruction by a single surgeon were analysed retrospectively. The PLC reconstruction was a modified Larson reconstruction of the lateral collateral ligament and the popliteofibular ligament. The IKDC and Tegner scores were used to assess outcome. Dial test and varus laxity were used to assess improvements in clinical laxity. Posterior laxity was tested using the KT-1000. RESULTS: The mean follow-up was 38 months (±(2× standard deviations), ±12.3). There were no postoperative complications. All patients had less than 5 mm posterior step-off. 17 of 19 patients had negative dial and varus stress tests. Measured range of motion was reduced by a mean of 10°, but patients did not report any daily activities restrictions. Tegner scores improved from a median pre-operative value of 2 (range 1-4) to 6 (4-9) at final follow-up. The mean postoperative IKDC score was 86 (±11). CONCLUSIONS: Subjectively, the knee stability achieved allowed daily activities. However, there were remaining abnormalities in range of motion, posterior drawer and rotational laxity, suggesting that normal knee laxity was not restored. LEVEL OF EVIDENCE: IV.