Innovations in the field of hip endoprostheses do not only require clinical examination and radiological control. Today an additional functional control of the hip replacement during walking is necessary. Purpose of the study is a comparison of a minimally invasive approach to a traditional approach by means of a biomechanical complex gait analysis. 21 patients (10 minimally invasive, 11 traditional) with a unilateral primary hip osteoarthritis are included in the study. The times of measuring - preoperatively (one day) and postoperatively (8, 14 and 27 weeks) - also show the rehabilitation in the course of time. A group of 20 healthy subjects serves as an age-matched control group. The relevance and novelty of this study lies in measuring the ground reaction forces and the electromyographical parameters after minimally invasive hip replacement at the same time. In addition, the instrumented treadmill allows recording all parameters under a standardized condition of a fixed treadmill speed. We also apply the short-form health survey SF-36 assessing the health-related quality of life. In the course of time both patient groups improve in gait velocity, in some temporal-spatial parameters, in some electromyographical parameters and in the health-related quality of life. Nevertheless, the level of the control group cannot be reached. The comparison of the different operation techniques shows slight advantages for the minimally invasive technique. However, these supposed advantages are not used to full capacity. After 27 weeks the patient groups do not show any significant differences anymore. Our results demonstrate that the potential benefit of the minimally invasive approach should receive more attention in the following rehabilitation process. Innovations in the medical field will only be successful in the long run, if communication and data networks between orthopaedic clinics, rehabilitation centres and gait laboratories improve in the future.