Short-term results of total hip replacement with metal-on-metal bearings and a large diameter femoral head

Abstract

Objective To evaluate the short-term results of total hip replacement with metal-on-metal bearings and a large diameter femoral head. Methods From January 2007 to July 2008, we treated 55 patients (60 hips) with large-diameter metal-on-metal bearings. They were 30 males and 25 females, with an average age of 48.1 years (range, 18 to 69 years). 60.0% of the patients were younger than 50 years old. Five cases underwent double hip replacement and 50 single hip replacement. The preoperative diagnoses included avascular necrosis of femoral head in 31, femoral neck fracture in 7, hip osteoarthrosis in 12, and ankylosing spondylitis in 5 cases. The Durom acetabulum and Metasul LDH large-diameter metal-on-metal bearings used were of non-cement type. Results For this series, the mean operation time was 70 min (50 to 85 min), mean blood loss 750 mL (450 to 1120 mL), and mean hospital stay 9.6 d (7 to 12 d). All the patients were followed up, with an average duration of 8.7 months (range, 3 to 19 months) . The mean Harris Hip Score improved from the preoperative 41 (15 to 82) to the operative 94. 7 (91 to 97) points. X-ray revealed fine position of the protheses without any loosening. Heterotopic ossification was not observed. Conclusions Metal-on-metal bearings with a large-diameter femoral heads can decrease the risk of dislocations and wear of the joint but increase joint range of motion. It is a good choice for young and active patients. Key words: Arthroplsty, replacement, hip; Hip prosthesis