Ceramic-on-Ceramic Bearing Total Hip Arthroplasty: Five-Year Midterm Follow-up Results

Purpose: We believe that cemented femoral stems will relieve the stiffness of ceramic-based bearings, resulting in reduced complication of ceramic-on-ceramic bearing total hip arthroplasty (THA). The purpose of this study was to evaluate the midterm effect of ceramic-on-ceramic bearing THA using cemented femoral stems. Materials and Methods: We studied 32cases (30 patients) of THA using ceramic-on-ceramic bearing cemented femoral stems and 33 cases (31 patients) of THA using ceramic-on-ceramic bearing cementless femoral stems. All total hip arthroplasties were performed between January 2004 and December 2005 and were followed up for more than 5 years. The clinical results and radiographic results were evaluated. Results: The mean HHS improved from points pre-operatively to points at the last follow-up in both the cemented and cementless stem groups (P<0.05). The mean WOMAC score also improved from points pre-operatively to points at the last follow-up in both the cemented and cementless stem groups (P<0.05). But no statistically significant difference was noted between the cemented and cementless stem groups in HHS and WOMAC scores (P=0.304, P=0.769). There were 3 patients with a sense of discomfort on ambulation and 5 patients with thigh pain in the cementless stem group and no cases in the cemented stem group. There was no instance of acetabular loosening in either group. Subsidenc of the cemented femoral stem was less than 1mm in 30 cases and less than 2 mm in 2 cases. All cementless femoral stems acquired firm bony union. Conclusion: Midterm results showed no statistical links between ceramicon-ceramic-bearing THA using cemented femoral stems or cementless femoral stems.