Functional recovery after total joint replacement in hip osteoarthritis: comparison between anterolateral mini-invasive versus posterior approach

Abstract

Purposes. One of the difficulties in evaluating functional recovery after total hip replacement (THR) in hip osteoarthritis lies in the fact that surgical assessment is mostly subjective. The aim of the study was to compare functional recovery after THR according to two different surgical approaches not only from a conventional clinical perspective but also with regard to a quantified gait analysis. Methods. Prospective pilot study comparing two THR approaches at short and medium terms: mini-invasive antero-lateral Rottinger approach vs. posterior ‘Moore’ approach in 25 patients suffering from hip osteoarthritis. Functional evaluation were performed using WOMAC questionnaire, Harris Hip Score and the Postel Merle d'Aubigne scores and 3D gait analysis including standard gait parameters, hip kinematics angles and postural analysis. Results. The effect size (>1) was high for both surgical approaches but statistically greater improvement in PMA was noted at D45 and D180 in favour of the RoA group. The 3D gait analysis at D180 did not reveal any difference between groups for the standard gait parameters. All of the patients had significantly increased their gait speed at 6 months (v0.9 m/s after THR). This improvement was induced by increased stride length, since step frequency was identical (data not shown). The only significant difference between groups for kinematics angles was greater hip abduction in the MoA group at 6 months (p= 0.024), which was not noted at baseline (p=0.14). Maximal hip extension seemed to be greater in both groups after THR, but the difference did not reach statistical significance. . A greater improvement in postural stability was also detected in this group . Conclusion. This study is the first to compare two specific references surgical approaches in term of functional recovery using validated subjective questionnaires and innovative 3D gait parameters. These results suggested that the Rottinger approach procured in terms of effect size faster clinical recovery than the Moore approach and better postural stability at 6 months for hip osteoarthritis patients. This postural gain might be explained by better preservation of the muscles involved in the pelvis stability in the standing position.