[Advantages of minimal invasive total hip replacement in the early phase of rehabilitation].

UNLABELLED: In arthroplasty the term "minimal invasive" not only refers to the length of the skin incision but more so to its soft tissue and thereby muscle-protecting features.

STUDY AIM: The aim of this study is to compare the early postoperative mobilisation and rehabilitation of the different surgical approaches in cementless total hip arthroplasty.

METHODS: 27 patients underwent a total hip replacement (Trilogy cup, MAYO stem) via a ventral minimal invasive approach (one incision technique) (MIS group). 23 patients underwent a total hip replacement with the same implant via a anterolateral transgluteal approach (standard group). We evaluated the Harris Hip Score (HHS), the visual analogue scale (VAS) for pain and patient satisfaction preoperatively as well as 3 days, 10 days, 6 weeks and 3 months postoperatively.

RESULTS: After 3 and 10 days the MIS group showed better scores for pain, gait and mobilisation as well as for the overall HHS compared to the standard group. These differences could not be shown 6 weeks postoperatively. The MIS group had a significantly higher rate of complications with 22 % transient impairment of the lateral cutaneous nerve.

CONCLUSION: The patients of the MIS group showed a better mobilisation and rehabilitation during the early postoperative period. This can be attributed to the lessened intraoperative damage of to soft tissue and especially muscle damage. Due to the increased rate of nerve irritations, we modified our surgical approach. The minimal invasive approach to modern hip joint arthroplasty remains a non-standard technique. Compared to the standard approach it carries additional risks (like nerve damage and malpositioning of the implants and thus should remain in the hands of the experienced orthopaedic surgeon in specialised orthopaedic centres.