The "jump sign" of the cadaver knees after the transection of the superficial medial collateral ligament.
We present a new test for the examination of the external rotatory instability of the knee caused by the section of the superficial medial collateral ligament. The test consists in a manoeuvre by which the proximal end of the tibia is pushed laterally and the medial femorotibial compartment is exposed to varus rotation stress. In the majority of cases, this causes an abrupt anterior slip of the medial tibial plateau accompanied by a click. The test was verified on 33 cadaver knees. It may be helpful in the differencial diagnosis of knee instability and intraarticular disorders. Key words: knee instability, medial collateral ligament.
Vanek
J
J
Service de Chirurgie Orthopédique, Centre Hospitalier Louis Pasteur, Cherbourg, Francie.