Functional evaluation in total hip replacement patients.

An evaluation of total hip replacement patients requires objective criteria that allow for the measurement of any changes in the biomechanics of the prosthesis and the effects of these changes on clinical findings. An evaluation of loading and joint movement during walking in these patients has been dealt with by many authors. In this study 15 patients who had undergone total hip replacement for coxarthrosis primary or secondary to congenital dysplasia were examined by kinematic and kinetic gait analysis, clinical evaluation, and radiographic evaluation of the position of the neocenter of prosthetic joint rotation. The patients with prostheses in congenital dysplasia presented with a pattern of walking that was significantly modified. In agreement with what is reported in the literature proximal positioning had less influence on gait parameters as compared to lateral dislocation. Furthermore, changes in positioning observed did not seem to have negative effects on joint loading, measured indirectly by the calculation of joint moments.