Acetabular dysplasia predicts incident osteoarthritis of the hip: The Rotterdam study

OBJECTIVE: To investigate the association between acetabular dysplasia and the incidence of radiographic osteoarthritis (OA) of the hip in a population-based sample of elderly subjects. METHODS: Radiographs of the hip at baseline and at followup (mean followup time 6.6 years) were evaluated in 835 men and women (age >or=55 years) from the Rotterdam Study. Subjects with a baseline Kellgren/Lawrence grade of 0 or 1 in both hips were included in the study. Incident radiographic OA of the hip was defined as a decrease of joint space width of the hip (>or=1.0 mm) at followup. Acetabular dysplasia was assessed using the center-edge angle and the acetabular depth. The association between acetabular dysplasia and incident radiographic hip OA was assessed by calculating odds ratios using multivariate regression analysis. RESULTS: In this study population with a mean +/- SD age of 65.6 +/- 6.5 years, 9.3% developed incident radiographic hip OA. Subjects with acetabular dysplasia (center-edge angle or=55 years, acetabular dysplasia is still a strong independent determinant of incident radiographic hip OA.