Motion analysis as an outcome measure for hip arthroplasty.

We review the available literature on the use of motion analysis as an outcome measure following total hip arthroplasty. Several studies have investigated spatio-temporal parameters of gait, kinematics, kinetics and electromyographic outputs following hip arthroplasty. We undertook to review all these studies to evaluate the value of motion analysis as an outcome measure. The search of the literature yielded eight studies. Motion analysis demonstrates functional improvement in patients post-operatively, but the values of the variables measured do not reach the same levels as control subjects. Motion analysis does not show much difference post-operatively between patients operated on by different technique or incision. Furthermore, motion analysis can identify subtle functional limitations which may not be detectable with conventional outcome measures.