The higher failure rate of total hip arthroplasty (THA) in young, active patients remains a challenge for surgeons. Recently, larger-diameter femoral heads combined with an alumina matrix composite ceramic (BIOLOX Delta; CeramTec AG, Plochingen, Germany) articulation was developed to improve implant longevity and meet patients' activity demands while reducing the risk of component-related complications. The purpose of this study was to determine whether this new device may provide advantages for young, active patients. A prospective, randomized, controlled trial was conducted on 93 patients (113 THAs) with more than 3 years of follow-up. Patients were randomly divided into a study group (51 THAs) with a 36-mm Delta ceramic-on-ceramic (COC) articulation and a control group (62 THAs) with a common-sized alumina ceramic head on polyethylene liner (COP) articulation. Clinical and radiographic results were collected to compare the outcomes and complications, including implant-related failures, osteolysis, and noises. The large-diameter Delta COC articulation provided greater range of motion improvement (6.1° more), similar Harris Hip Scores, and similar complication rates compared with the alumina COP articulation. This study suggests that in the short term, the large-diameter Delta COC articulation results in better range of motion with no higher complication rates; however, mid-term (8-10 years) or longer follow-up is necessary to determine its superiority in young, active patients.

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This study explored the surgical method and short-term clinical effect of a greater trochanter osteotomy along with cementless artificial total hip arthroplasty in the treatment of Crowe type IV developmental dysplasia of the hip. The authors conducted a retrospective analysis of 18 patients (22 hips) with Crowe type IV dysplasia who were seen between June 2008 and August 2010. After undergoing cementless artificial total hip arthroplasty using a posterolateral approach, a greater trochanter osteotomy was used to adjust the tension of the gluteal muscle, and an acetabular cup was placed. Average preoperative length shortening of the affected limb was 4.5 cm (range, 3.4-6 cm), and average postoperative length increase was 4.0 cm (range, 3.2-4.8 cm). Average postoperative Harris Hip Score was 87 (range, 79-91), which was higher than the average preoperative score of 38 (range, 32-51). Intraoperatively, 3 hips (3 patients) sustained a proximal femur fracture. Due to the stability of the femoral prosthesis, either no treatment or wire fixation only was given; by 2 months postoperatively, radiographs indicated that all fractures had healed. One patient had symptoms of sciatic nerve paralysis that resolved 3 months postoperatively. Performing a greater trochanter osteotomy after cementless artificial total hip arthroplasty is effective for the treatment of Crowe type IV dysplasia and can rebuild the complex biology and biomechanics of hip dysplasia without increasing the complication risk.