Cross-sectional and longitudinal associations between radiographic features and measures of pain and physical function in hand osteoarthritis.

OBJECTIVE: Previous longitudinal studies have shown no associations between increasing amount of radiographic hand osteoarthritis (OA) and levels of hand pain/disability. In this longitudinal study, we aimed to study whether radiographic hand OA was related to pain/disability in cross-sectional and longitudinal settings focusing on joint-specific analyses.

METHODS: We included 190 patients (173 women, mean (standard deviation, SD) age 61.5 (5.7) years) from the Oslo hand OA cohort, of whom 112 had 7-year follow-up data. Finger joints were scored for radiographic OA according to the Kellgren-Lawrence scale and Osteoarthritis Research Society International (OARSI) atlas. Pain and function were assessed by clinical examination (joint tenderness), grip strength and the Australian/Canadian (AUSCAN) questionnaire. Associations between radiographic hand OA and tenderness in the same joint were examined by logistic regression analyses with Generalized Estimating Equations, whereas associations between overall amount of radiographic OA and hand pain/disability were assessed by linear regression (adjusted for age and sex).

RESULTS: A dose-dependent association was found between the severity of radiographic OA and tenderness in the same joint. Joints that progressed into severe radiographic OA during follow-up had the highest odds of developing tenderness (OR = 11, 95% confidence interval (CI) 4.0-33). Incident erosions seemed to be the most important individual feature associated with incident tenderness (OR = 6.2, 95% CI 3.2-12). Weak associations were found between the amount of radiographic hand OA and overall hand pain/disability.

CONCLUSION: Radiographic hand OA is associated with tenderness in the same joint, and erosive development strongly predicts future joint tenderness independent of other radiographic features.