ObjectiveTo investigate the clinical characteristic differences of cementless total hip arthroplasty (THA) between with and without subtrochanteric femoral shortening osteostomy in Crowe type IV developmental dysplasia of the hip (DDH). MethodsBetween January 2006 and March 2012, 21 patients (21 hips) with Crowe type IV DDH who underwent primary THA were enrolled according to inclusion criteria. According to whether subtrochanteric femoral shortening osteostomy was performed during THA or not, the patients were divided into 2 groups: THA with osteostomy group (n=9) and THA without osteotomy group (n=12). There was no significant difference in gender, age, body mass index, and hip Harris score between 2 groups (P>0.05) except leg length discrepancy (t=-3.170, P=0.005). The operation time, blood loss, postoperative drainage, complications, and radiography data were compared to evaluate the clinical characteristics. ResultsThe operation time, blood loss, and postoperative drainage of osteotomy group were all significantly greater than those of no osteotomy group (P<0.05). All patients achieved primary healing of incision; 1 patient (1 hip) had transient sciatic nerve symptom in osteotomy group. The average follow-up time was 53 months (range, 28-88 months). The X-ray films showed good fracture healing at 3-6 months after operation in osteostomy group. No prosthetic loosening or dislocation was found. The hip Harris score was 90.67±4.06 in osteostomy group and 92.17±3.27 in no osteostomy group, showing no significant difference between 2 groups (t=-0.938, P=0.360). The leg length discrepancy was (0.22±0.26) cm in osteostomy group and (0.18±0.27) cm in no osteostomy group, showing no significant difference (t=107.000, P=0.546). The leg length discrepancy was found in 6 patients of osteotomy group and 5 patients of no osteotomy group. One patient complained of thigh pain in osteotomy group; 2 patients had slight limp (Trendelenburg +) in no osteotomy group. ConclusionTHA can improve joint function and increase limb length in the treatment of Crowe type IV DDH. Subtrochanteric shortening osteotomy is an effective treatment which can be performed according to preoperative template measurement, leg length shortening, and the soft tissue tension.