The gait variables most sensitive in giving evidence of a change in a patient's ambulatory status were maximal vertical force and average velocity followed by step rate, single limb support, and weight acceptance - all measurements of weight bearing capacity. Maximal vertical force and average velocity were the only gait variables that could distinguish the one type of THR from the other. In correlations between the clinical impression of gait function and its objective registration the strongest correlations were found in maximal vertical force and average velocity. Thus, gait analysis is considered a useful tool in the evaluation of locomotor function after surgical procedures.