Total hip arthroplasty (S-ROM stem) and subtrochanteric osteotomy for Crowe type IV developmental dysplasia of the hip

Background: Developmental dysplasia of the hip (DDH) in adults with severe pain and disability is best treated by total hip arthroplasty (THA). The purpose of this study was to retrospectively evaluate the outcomes of subtrochanteric shortening osteotomy combined with THA using S-ROM stem for those severe patients with a special focus on the effect of two shapes in the subtrochanteric osteotomy ends: Oblique and transverse. Materials and Methods: Twenty one cases with mean age of 43.6 years who met inclusion criteria and were operated between February 2007 and February 2012 were included in the study. Those cases had been divided into two groups (oblique vs. transverse) and all records between the two groups were analyzed. Results: The Harris hip score significantly improved from 30.6 (range 18u59) preoperatively to 91.2 (range 87u98) postoperatively by the latest followup. Complications including one deep venous thrombosis, one intraoperative fracture of femur and two dislocations occurred while they were addressed properly afterward. The oblique group showed significant advantages in operative time, union time and additional fixation in comparison with the transverse group. Conclusions: In the primary THA for the treatment of irreducible DDH, subtrochanteric oblique osteotomy combined with the freely-rotatable S-ROM stem provided favorable short term outcomes by affording both morphological and functional advantages.