[Surgical hip dislocation : Current status in the treatment of femoral acetabular impingement].

INTRODUCTION: Surgical hip dislocation (SHD) in the therapy of femoral acetabular impingement (FAI) has been mostly replaced by minimally invasive techniques. Nevertheless, in the circumstances of complex FAI types and combined impingement located in inaccessible areas of the hip, SHD is an option to reach those deformities. The advantage of the complete overview of the hip joint enables the circumferential therapy of bony deformity, but at the expense of higher invasivity. In the literature there is still a lack of mid to long-term studies of SHD to determine the overall treatment outcome. Therefore, the aim of this study is to evaluate the treatment outcome, risks and complications of SHD in FAI therapy within a mid-term follow-up.

METHODS: A total of 43 patients (mean follow-up 54 months.) with combined ventral and dorsal impingement who undertook SHD were retrospectively reviewed. Outcome parameters were range of motion (ROM), the Harris hip score (HHS), the hip outcome score (HOS), the activity level, pain, complications, conversion to total hip arthroplasty (THA) and patient specific surveys. Additionally, radiographs and the influence of preoperative osteoarthrosis were evaluated.

RESULTS: We were able to demonstrate a significant increase of ROM, HHS (69 → 80 Pkt.; p < 0.05), hip function and a decrease in pain level. The return to sport rate was 81%, but in most cases the patients had to reduce the intensity or change to a low impact sport activity. Overall, 75% were satisfied with the treatment outcome. The alpha angle improved from 70 to 45° (p < 0.05). Patients with preoperatively advanced hip osteoarthrosis showed no decent improvement of hip function. Conversion to THA was necessary in 36% of cases. The complication rate was about 13%.

CONCLUSION: SHD is successful in the treatment of combined ventral and dorsal impingement within a mid-term follow-up. The improvement of hip function and the reduction of pain symptoms is possible. In case of a manifest arthrosis an indication for SHD is no longer reasonable.