Single-bundle versus double-bundle posterior cruciate ligament reconstruction: scientific rationale and surgical technique.

Despite many recent advances in the understanding of the posterior cruciate ligament (PCL) and its function, the optimal treatment of PCL injuries remains controversial. Although it now is well known that the PCL is made up of two distinct bundles, each of which plays a vital role in achieving knee stability, questions abound regarding the need for double-bundle reconstruction rather than single-bundle techniques. Currently, the reconstruction technique is selected based on the injury pattern. In acute (< 3 weeks from the time of injury) combined PCL injuries (PCL/posterolateral corner, PCL/medial collateral ligament, and knee dislocations), a single-bundle reconstruction designed to replicate the anatomy of the anterolateral bundle is used. In acute or chronic PCL injuries in which both the posteromedial bundle of the PCL and the meniscofemoral ligaments remain intact, a single-bundle augmentation is used. A double-bundle reconstruction is performed when all three components of the PCL complex (anterolateral band, posteromedial band, and meniscofemoral ligaments) have been ruptured. These patterns are generally chronic, with severe knee laxity following a previous traumatic injury (PCL/posterolateral corner or knee dislocation). Tailoring the PCL reconstruction technique to the individual injury pattern will likely yield a reconstruction that better replicates the natural biomechanics of the native knee, thereby resulting in better functional outcomes.