Cementless Total Hip Arthroplasty using Metal on Metal Articulation

Kim, Shin Yoon; Oh, Chang Wug; Kim, Young Woo; Park, Il Hyung; Park, Byung Chul; Kim, Poong Taek; Ihn, Joo Chul

Abstract

PURPOSE
To evaluate the early midterm clinical and radiographic results of cementless total hip arthroplasty using Metasul metal-on-metal articulation. MATERIALS AND METHODS: Seventy-four (63 patients) of ninety three consecutive total hip arthroplasties (81 patients) using a metal on metal bearing surface and implanted from November, 1994 to April, 1998 with a minimum 3 year follow-up were analysed clinically and radiographically. The mean age at the time of index operation was 43.1 years (range; 17-65 years) and the mean follow up period was 61.2 months (range; 36-90 months). Clinical evaluation was performed by awarding Harris Hip scores (HHS). Radiographic evaluation was performed in terms of the stability of components, osteolysis, and wear rate. RESULTS: The average Harris hip score was 49.4 preoperatively and 91.4 at the most recent follow-up evaluation. Excellent or good results were found in 67 hips (90.5%). Two femoral components were loose radiographically, and one of the loose components was revised due to subsidence. Two acetabular components were revised (1 loosening and 1 continuous radiolucent line). One diffuse pelvic osteolysis was found around a stable component. Wear could not be measured radiographically. CONCLUSION: Compared to other bearing surface, total hip arthroplasty using a metal-on-metal bearing surface demonstrated very low wear rates and osteolysis at an average 5 year follow up results, however, a longer follow up is needed to evaluate wearinduced osteolysis.