Knee dislocations: is reconstruction of the posterior cruciate ligament crucial?

The purpose of the present study was to investigate our 6-10 year results for knee dislocations with posterolateral corner (PLC) involvement, where a primary repair was performed laterally, the anterior cruciate ligament (ACL) reconstructed, but the posterior cruciate ligament (PCL) was left without surgery. Four consecutive patients with knee dislocation with complete rupture of the ACL, the PCL and the PLC were operated on by the same surgeon with similar technique. There were no other major injuries. We used strict inclusion criteria to get as homogenous population as possible. The ACL injuries were reconstructed and the PLC primary repaired, but the PCLs were not reconstructed. After 1-5 years, KOOS, EQ5D and work performance were recorded. Five years later these scores were repeated, with addition of the Lysholms and Tegners, standing radiographs and posterior stress radiographs. All patients were working fulltime from 1 year postoperatively onwards. One patient had returned to high-level sports activities, but the other three had lowered their activity. One patient had slight joint space narrowing at standing radiographs, but the other three appeared normal. All patients had increased posterior laxity with stress radiographs, and the tibiae were positioned more posterior with standard standing radiographs. Patients with knee dislocations where the PCL had not been reconstructed performed fairly good after more than 6 years. This study does not show that leaving the PCL in a dislocated knee is better than reconstructing it, but it may be an acceptable option.