Subtrochanteric rotational osteotomy for young adults with hip pain due to femoral maltorsion.

Introduction: Femoral rotational osteotomies can be a treatment option for symptomatic femoral maltorsion. This study investigated the clinical and radiological results of subtrochanteric rotational osteotomy and its potential adverse effects, particularly on patellofemoral stability and geometry.

Methods: Retrospective consecutive series of patients undergoing subtrochanteric rotational osteotomy with hip arthroscopy. 25 hips, 18 with decreased (⩽4°), 7 with increased (⩾28°) femoral torsion (FT), were analysed. Mean follow-up was 37 months. Subjective Hip value (SHV), WOMAC and Harris Hip Score (HHS), hip range of motion, asymmetries in foot position during gait as well as patellofemoral instability were the outcome measures. Femoral and tibial torsion as well as morphological signs of patella maltracking (TTTG, patellar tilt and lateralisation) were measured on MRI.

Results: SHV improved from 52% to 72% ( = 0.002), WOMAC from 3 to 1 ( < 0.001) and HHS from 68 to 86 ( < 0.001). Hips treated for reduced FT showed better internal rotation and hips treated for excessive FT less internal rotation compared to the opposite side. 1 patient demonstrated asymptomatic minor in-toeing. Objective patellofemoral instability was not found except for in 1 patient with bilateral patellofemoral apprehension. FT was normalised (mean 16° ± 9°). Tibial torsion showed normal values. Compared to the opposite side TTTG ( > 0.08), patellar tilt ( > 0.09) and lateralisation ( > 0.26) did not differ. No complications occurred.

Conclusions: Subtrochanteric rotational osteotomy with hip arthroscopy improves the hip subjectively without leading to objective patellofemoral instability nor changes in the patellofemoral geometry compared to contralateral side. The technique of subtrochanteric rotational osteotomy is safe and reliable.