The role of lateral extra-articular procedures for anterolateral rotatory instability.

The goal of any surgical procedure to correct the instability caused by loss of the ACL is to control the abnormal anterior excursion of the tibia on the femur. Because the main problem is loss of the ACL, it would seem most reasonable to approach this problem by performing an intra-articular reconstruction of the ACL, thus approximating as closely as possible the normal anatomy of the ACL. The classic open intra-articular ACL reconstructions are technically demanding surgical procedures that usually require a significant "learning curve" to achieve a level of technical expertise and confidence. In addition, postoperative complications such as adhesions, loss of motion, prolonged muscle atrophy, and a long rehabilitation period are well known. Thus, it would appear that the extra-articular reconstructive procedures for the anterior cruciate-deficient knee would offer some advantage over these more formidable surgical procedures. Whereas the main problem is certainly the loss of the ACL, the extra-articular procedures are directed more toward the most symptomatic anterior excursion of the tibia on the femur, the pivot shift phenomenon, where the anterolateral portion of the tibia moves anterior in relation to the femur. Thus, the goal of the extra-articular reconstructive procedures for anterolateral rotatory instability is to eliminate functional instability. These goals are most readily achieved by positioning some portion of the iliotibial tract posterior to the transverse center of rotation of the knee to provide a reinforcement for the lateral tibial plateau as the knee approaches terminal extension. All of the extra-articular procedures discussed in this article have been used successfully as reported by the various authors. There are many technical details inherent in each of these surgical procedures, and the reader is referred to the original articles for a more explicit description of these surgical procedures. For the individual surgeon to participate in and view the actual surgical procedure that he or she intends to perform would be the ideal situation. Various workshops where surgical procedures of the knee are actually performed and studied are currently available and are of great value to the surgeon. Of equal importance to the technical demands of the various surgical procedures is selection of the appropriate procedure for each patient. The selection must be based on many factors. The most important factor is the identification of the patient with a high level of athletic activity who is unwilling to modify his or her activity level to compensate for a deficient ACL.(ABSTRACT TRUNCATED AT 400 WORDS)