In this study, cementless THA was performed for RA patients, and its clinical outcomes, as well as radiographic findings and implant survival rates, were examined more than 10 years after surgery in comparison with the outcomes of the same procedure performed for patients with hip osteoarthritis (OA) during the same period.
We studied 28 cases of THA for RA clinically and radiologically at a minimum follow-up duration of 10 years. The patients consisted of 4 males and 22 females, with a mean age at the time of surgery of 53.1. The clinical and radiographic results were compared with an age-matched and sex-matched group of patients who had undergone THA for the diagnosis of primary or secondary OA.
In the RA group, the mean Harris hip score was 48.3 before surgery, and improved to 76.8 at the time of the final survey. In the control group, the score also improved from 46.8 before to 86.5 after surgery, while revealing significant differences between the groups (p = 0.0002). In the RA group, 2 joints required revision THA on the acetabular side due to aseptic loosening, while such revision was not performed on the femoral side despite the presence of more than 2 mm of subsidence in 2 joints. The implant survival rate was 92.9 and 100 % in the RA and control groups, respectively, without significant differences (p = 0.493).
Although its clinical outcomes were significantly different from those for OA, a satisfactory implant survival rate was achieved, at 92.9 % in RA patients.