Combined chronic posterior cruciate and posterolateral corner ligamentous injuries: a comparison of posterior cruciate ligament reconstruction with and without reconstruction of the posterolateral corner.

Many have advocated the importance of correcting posterolateral rotatory instability (PLRI) in injuries causing rupture of the posterior cruciate ligament (PCL) and posterolateral corner. However, there have been few studies directly comparing the results of reconstructing the PCL in isolation with PCL reconstruction combined with stabilisation of the posterolateral corner. We report on a retrospective study into 17 consecutive patients with chronic combined posterior cruciate and posterolateral corner ligamentous injuries. The mean follow-up was 35 months (range 14-74 months). All patients had unstable knees, with significant PLRI. In 12 cases the PCL alone was reconstructed, in 5 cases a combined PCL and posterolateral corner reconstruction was performed. At a mean follow-up of 35 months, both groups had significantly improved compared to their pre-operative status, as measured by Lysholm and Tegner scores and clinical examination (P<0.01). The group in which only the PCL was reconstructed had significantly lower scores compared to those who had the additional posterolateral corner reconstruction (Tegner P<0.04, Lysholm P<0.02).