A prospective cohort study on cam morphology and its role in progression of osteoarthritis

Abstract

Background: Cam morphology contributes to the development of hip osteoarthritis (OA) but is less studied in the general population. This study describes its associations with clinical and imaging features of hip OA. Methods: Anteroposterior hip radiographs of 1019 participants from the Tasmanian Older Adult Cohort (TASOAC) were scored at baseline for α angle (cam morphology) in both hips. Using the Altman's atlas, radiographic hip OA (ROA) was assessed at baseline. Hip pain and right hip structural changes were assessed on a subset of 245 magnetic resonance images (MRI) at 5 years. Joint registry data for total hip replacement (THR) was acquired 14 years from baseline. Results: Of 1906 images, cam morphology was assessed in 1016 right and 890 left hips. Cross-sectionally, cam morphology modestly associated with age (prevalence ratio [PR]: 1.02 P =.03) and body mass index (BMI) (PR: 1.03-1.07, P =.03) and strongly related to male gender (PR: 2.96, P