OBJECTIVETo study the characteristics and clinical effect of total hip arthroplasty(THA) for osteoarthritis and (or) avascular necrosis of femoral head after failure of internal fixation of acetabular fracture.

METHODSFrom February 2009 to October 2014, 31 patients (31 hips) with hip traumatic osteoarthritis and (or) femoral head avascular necrosis after failure of internal fixation of acetabular fracture were treated with THA including 26 males and 5 females, who injured when the average age of(41±12) years. THA were performed, and the duration ranged from 3 to 132 months with a mean of(20.6±26.9) months secondary to traumatic osteoarthritis and(or) femoral head avascular necrosis. All THA were performed with posterior-lateral approach. The postoperative complications were observed. VAS and Harris hip scores were compared pre-operation and post-operation.

RESULTSTwenty-seven cases were followed up, and the duration ranged from 12 to 80 months with a mean of (43.2±11.7) months. One patient had infection around prosthesis. Aseptic loosening occurred in 1 patient, dislocation of prosthesis in 1 patient. No sciatic nerve injury occurred. Hip function and gaits were obviously improved. To the last follow-up, VAS score was decreased from 7.6±1.2 pre-operatively to 1.2±0.9 post-operatively, while the Harris score was improved from 45.5±13.6 pre-operatively to 88.5±7.8 post-operatively, both differences were statistically significant(<0.01). The post-operative ROM of hip was significantly improved compared to pre-operative ROM(<0.05), in addition to extension motion. X-ray showed all the acetabular cups were stable, one femur stem subsided 3 mm. Heterotopic ossification occurred in 2 cases.

CONCLUSIONSCorrect dealing with of internal fixation implants, looking out potential infection and reasonable reconstruction of acetabular bone deficiency were the key to the success of THA for osteoarthritis and(or) avascular necrosis of femoral head after failure of internal fixation of acetabular fracture.