Posterolateral knee instability: an alternative proposal for surgical treatment.

In spite of the low incidence of posterolateral instability of the knee, its recognition has become highly important, because lack of diagnosis leads to severe sequelae, mainly when associated with anterior and/or posterior cruciate ligament injuries, evolving to varus deformity, hyperextension, and failure of the primary ligament reconstructions of this joint in those cases where they are performed. Observing the evolution of reconstructive surgeries for knee ligament injuries, we found that improvement is still needed, since some of the performed procedures show sequelae, and we noticed the failure of primary reconstructions secondary to lack of early recognition of other peripheral failures such as posterolateral corner instability. In the knee with a chronically affected posterolateral corner, the main objective is to restore the biomechanical stability so that the patient can attain the same level of activity enjoyed before the injury. However, it is very difficult to reach this desirable level, mainly because these injuries are very complex. A variety of surgical techniques have been described, although often with moderate results. Several studies on anatomical structures to be repaired, plus the determination of dynamic isometric points on the femur and head of the fibula, promote an increased opportunity to obtain stable knees. There is no consensus on the best technique to use for repairing injured lateral and posterolateral structures of the knee, since this instability involves many anatomical factors as well as the determination of static and dynamic isometric points to be adopted for these reconstructions. SURGICAL TECHNIQUE