Seventy-seven patients receiving either unilateral or bilateral total
hip replacement were studied before and for as long as four years after
operation. Their walking velocity and efficiency (the latter determined by
measuring oxygen consumption) improved after operation. Total hip
replacement allowed relatively equal postoperative efficiency and velocity
for patients with unilateral and bilateral disease. While no consistent
relationships were found between the components of the Iowa hip-rating
scale, significant correlations were found between the composite Iowa
hip-rating score and oxygen consumption. Data indicate that measurement of
self-selected velocity in patients with hip disease is a satisfactory
indicator of walking efficiency.