Objective: To discuss the diagnosis and treatment of posterolateral corner injury of the knee joint, and to evaluate the clinical results after anatomical reconstruction.
Methods: Sixteen cases of posterolateral corner injury of the knee were treated, being accompanied with grade II or above existing serious varus or external rotation. At a mean follow-up of 13 months (7 to 18 months), we evaluate the clinical results using Lysholm and IKDC (international knee documentation committee) scoring systems. Among them, there were 14 males and 2 females aging 19-46 years (mean 38 years). It was 4-12 d from injury to operation. On conditions of anesthesia, varus stress test (VST) showed that instability of varus was more than 10 degrees under the 30 degrees and 0 degrees of genuflexion respectively and external rotation test showed that instability of external rotation was more than 10 degrees when compared with normal side. Five cases complicated by rupture of anterior cruciate ligament, 8 cases by rupture of posterior cruciate ligament and 3 cases by rupture of both ligaments.
Results: All patients were followed 7 to 18 months and no patients had instability of the knee. The VST showed that no abnormal lateral instability was found at 0 degrees of flexion except 3 cases at 30 degrees with less than 5 degrees. Cooper test showed that no rotational instability at 90 degrees except 1 cases at 30 degrees with less than 5 degrees. The range of motion of the knee was from 75 degrees to 130 degrees of flexion(mean 118 degrees)and from 0 degrees to 5 degrees of extension. Posteroperative scores were from 54 to 96 according to Lysholm scoring systems and from 46 to 94 according to IKDC scoring systems.
Conclusion: Although the overall incidence of posterolateral corner injury is less than that of other ligament injuries of the knee, we should pay much attention to posterolateral corner injury because of its important role in resisting posterior tibia translation, external rotation and varus of knee. This injury can result in a significant degree of disability for patients.