A new test--the posteromedial pivot-shift test--was used to demonstrate
a rupture of the posterior cruciate ligament of the knee in six patients.
An anatomical study of seventeen specimens showed that in order for the
posteromedial pivot shift to occur, the posterior collateral ligament, the
medial collateral ligament, and the posterior oblique ligament must be cut;
if one of these three ligaments is intact, the subluxation will not
occur.