Anterior Subluxation of the Lateral Tibial Plateau

Abstract

In our classification, anterolateral rotatory instability in the knee may occur either in flexion or as the knee approaches extension. The former condition, anterolateral rotatory instability in flexion, corresponds with its opposite number, the anteromedial rotatory instability that JAMES and SLOCUM have described so well. We do not think that anterolateral rotatory instability in flexion is an important instability. However, anterolateral rotatory instability as the knee approaches extension has been popularized in North America by McINTOSH with his description of the pivot shift test, by HUGHSTON with his so-called jerk test, and finally by ELLISON who devised his rather simple, ingenious operation of the fascia rerouting. I personally would like to pay tribute to Dr. McINTOSH of Toronto for his astute and original observation pertaining to the clinical entity of anterolateral rotatory instability as the knee approaches extension. However, in the United States there has certainly been a great deal of confusion as to the interpretation of the many features of anterior subluxation of the lateral tibial plateau. These include problems such as: What are the basic structural defects to produce this symptom? What are the specific clinical tests? When are they positive? And finally, what technique should you select to correct this disabling entity?