Patterns and natural history of hand pain in individuals with symptomatic hand osteoarthritis in a prospective cohort study: A post-hoc analysis of a randomised controlled trial

Objective: To investigate the variation in the distribution and the natural history of hand pain over 6 weeks in individuals with symptomatic hand osteoarthritis. Design: Patient-reported outcome data were collected at baseline and weekly for 6 weeks from community-based participants enrolled in a randomised controlled trial. Participants were grouped based on location of significant pain (Visual Analogue Scale, VAS >= 40/100 mm) (both carpometacarpal (CMC) and interphalangeal (IP), CMC only, and IP only). Results: At baseline, of the 106 participants, 55(51.9 %) had pain in both CMC and IP joints, 28(26.4 %) in IP joints only, and 16(15.1 %) in CMC joint only. Those with CMC and IP pain had significantly higher VAS pain [68.1 (2.6) vs 59.3 (3.5) vs 51.2 (4.7)]; Australian Canadian Osteoarthritis Hand Index, (AUSCAN) pain [290.1 (15.7) vs 225.3 (21.2) vs 237.9 (28.4)], stiffness [57.1 (3.7) vs 44.6 (5.0) vs 32.2 (6.7)] and functional limitation [527.5 (30.9) vs 356.0 (41.7) vs 433.3 (55.7)]; and pain sensitization [PainDETECT score 11.1 (1.1) vs 8.1 (1.8) vs 5.8 (1.9)] compared to those with IP or CMC only pain, respectively. All groups showed improvement in outcomes over 6 weeks without significant inter-group differences. Conclusion: In a population with significant hand pain, pain in both CMC and IP joints was most common and identified a more severe phenotype than pain in IP or CMC only with higher pain, more functional limitation and pain sensitization. These data have the potential to inform clinical management of patients with hand pain and patient selection in clinical trials.