Rotational motion of the knee: a comparison of normal and pronating subjects.

The existence of excessive subtalar joint pronation has been found to be common in the American population. Pronation has been shown to cause obligatory internal rotation of the tibia, placing stress on the knee joint. The purpose of this study was to investigate the effect of the excessive pronation on transverse rotational motion of the knee. Fifteen normal and 15 pronating subjects were tested for the total range of passive transverse rotatory movement of the knee. All subjects were tested for knee rotation on the Cybex II(R) isokinetic dynamometer with the knee flexed 90 degrees , 15 degrees and 5 degrees .Data analysis demonstrated that tibial rotation was significantly greater in the pronating group in comparison to the normal group at 5 degrees of knee flexion. The results suggest that further study be undertaken to examine the possibility of excessive pronation causing increased transverse rotational motion of the knee joint. J Orthop Sports Phys Ther 1989;10(9):366-369.