Association between pain catastrophizing and disability in thumb carpometacarpal osteoarthritis: a cross-sectional register-based study

The aim of this study was to evaluate association between pain catastrophizing and disability in patients with carpometacarpal osteoarthritis of thumb. In this cross-sectional register-based study, main methods were Spearman correlation and linear regression. Main outcome measures were the Pain Catastrophizing Scale (PCS) and the Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH). Of 113 patients, 64 (57%) were women and mean age was 54.0 (16.4 SD) years. The total PCS score was 14.0 (11.0 SD) points. The total QuickDASH score was 41.0 (22.4 SD) points. There was a moderate positive association between the total scores of the PCS and the QuickDASH (ρ = 0.57). Most of the items of both scales demonstrated a moderate positive association with each other. Rumination and helplessness subscales associated moderately with each QuickDASH items as well as with the QuickDASH total score. Although magnification subscale scores associated moderately with the QuickDASH total score, there was only weak association with some of the individual QuickDASH items. The regression coefficient for total scores was 1.09 (95% CI 0.77 to 1.41). This cross-sectional register-based study demonstrated a moderate positive association between pain catastrophizing and self-reported disability among patients with carpometacarpal osteoarthritis of thumb (thumb CMC OA). Among the PCS subscales, helplessness showed the strongest association with disability. Although causality cannot be inferred from the present findings, assessment of pain catastrophizing may help clinicians interpret patient-reported disability more comprehensively in patients with thumb CMC OA.