Novel methods for diagnosis and treatment of posterolateral rotatory instability of the knee

Abstract

Injury to the posterolateral corner structures of the knee can cause posterolateral rotatory instability, a condition that has attracted increased attention over recent years1. This injury is often associated with cruciate ligament injury, and its diagnosis can be difficult unless one has a high degree of clinical suspicion for an injury to the posterolateral corner structures2,3. Although a number of treatment methods have been proposed over the past twenty years2,4-12, there has been considerable controversy regarding the optimal method of surgical treatment for this injury. The consequences of missed or unsuccessfully treated posterolateral rotatory instability can be profound: reconstructed anterior or posterior cruciate ligaments can fail, and persistent posterolateral rotatory instability may eventually cause pain, instability, and even degenerative changes13-17. In this report, we describe the use of an external rotationvalgus stress radiograph for the evaluation and diagnosis of posterolateral rotatory instability, and we describe a new anatomical reconstruction procedure involving use of a split Achilles tendon allograft for its treatment.