Abstract
Knee flexion and sagittal tibial translation were measured during stair ascent and descent as well as during maximal isokinetic concentric muscle work with an electrogoniometer chain in ten volunteers without previous knee injury. The tests were repeated 16 times for each knee on different occasions by two examiners. The standard deviation for repeated measurements was ± 1.3 mm and the 95% confidence interval for the difference between repeated measurements was ± 0.9 mm. The test-retest correlations were above 0.80 for the whole group of subjects. There were no significant differences between the right and left knee, different sessions or examiners. There was a wide range in the amount of translation between different individuals from 2.7 to 10.2 mm. The translations during stair walking were 30–50% smaller than during isokinetic muscle work and the coefficient of variation was therefore higher. There was no difference in translations between stair ascent and stair descent but the amount of translation was larger for cycles ending with both feet carrying body weight than for single support cycles. It is suggested that higher contact forces in the knee diminishes the amount of sagittal translation. This finding indicates that closed kinetic chain exercises may be preferable to minimize translatory forces in the rehabilitation after reconstruction of the cruciate ligaments.