Most of patients with femoral derotation osteotomy for posterior extraarticular hip impingement and high femoral version would do surgery again.

AIMS To assess (1) hip pain and function and ROM; (2) subsequent surgeries, complications; and (3) subjective satisfaction and PROMs in patients undergoing femoral derotation osteotomies. METHODS Femoral derotation subtrochanteric osteotomies to treat symptomatic posterior extraarticular ischiofemoral hip impingement were performed in 23 patients (25 hips) between 2013 and 2017. The mean age was 26 ± 8 years (96% female) with a minimum 2-year follow-up (mean follow-up of 4 ± 1 years). Surgical indication was a positive posterior impingement test and limited external rotation (mean 16° ± 8°) in extension in patients with abnormal high femoral version (mean 46° ± 9, measured on CT scans with the Murphy method) and high McKibbin instability index (mean 67°). Femoral osteotomies were combined with a surgical hip dislocation in 96% for cam resection and labrum or cartilage treatment. Preoperative MRI and 3D-CT with dynamic impingement simulation were evaluated. RESULTS (1) The posterior impingement test decreased significantly from preoperatively 100% to 4% (p < 0.001). External rotation in extension increased significantly (p < 0.001) from preoperative 16° ± 8 to 44° ± 16°. The MdA score increased significantly from 14 ± 1 to 16 ± 2 (p < 0.001) points.(2) At follow-up, all 25 hips were preserved. No conversion to THA and no revision osteosynthesis was performed. 64% underwent complete hardware removal.(3) 80% of the patients reported at follow-up that they would undergo surgery again. Subjective satisfaction (SHV) increased significantly (p < 0.001) from preoperatively 24% to 84% postoperatively. CONCLUSIONS Femoral derotation subtrochanteric osteotomies for the treatment of posterior extraarticular ischiofemoral hip impingement are safe and improve posterior hip pain and function and external rotation in mostly female patients with high femoral version and a high McKibbin instability index.