Exercise Therapy in Addition to an Orthosis Reduces Pain More Than an Orthosis Alone in Patients With Thumb Base Osteoarthritis: A Propensity Score Matching Study

Abstract

Objective: To compare the effect of exercises and orthotics with orthotics alone on pain and hand function in patients with first carpometacarpal joint (CMC-1) osteoarthritis (OA) and to predict outcomes on pain and hand function of exercises and orthotics.

Design: Prospective cohort study with propensity score matching.

Setting: Data collection took place in 13 outpatient clinics for hand surgery and hand therapy in The Netherlands.

Participants: A consecutive, population-based sample of patients with CMC-1 OA (N=173) was included in this study, of which 84 were matched on baseline demographics and baseline primary outcomes.

Interventions: Exercises and orthotics versus orthotics alone.

Main outcome measures: Primary outcomes included pain and hand function at 3 months, measured using visual analog scale (VAS, 0-100) and the Michigan Hand Outcomes Questionnaire (MHQ, 0-100).

Results: A larger decrease in VAS pain at rest (11.1 points difference; 95% confidence interval, 1.9-20.3; P=.002) and during physical load (22.7 points difference; 95% confidence interval, 13.6-31.0; P<.001) was found in the exercise + orthotic group compared to the orthotic group. In addition, larger improvement was found for the MHQ subscales pain, work performance, aesthetics, and satisfaction in the exercise + orthotic group. No differences were found on other outcomes. Baseline scores of metacarpophalangeal flexion, presence of scaphotrapeziotrapezoid OA, VAS pain at rest, heavy physical labor, and MHQ total predicted primary outcomes for the total exercise + orthotic group (N=131).

Conclusions: Non-surgical treatment of patients with CMC-1 OA should include exercises, since there is a relatively large treatment effect compared to using an orthosis alone. Future research should study exercises and predictors in a more standardized setting to confirm this finding.

Keywords: Carpometacarpal joint; Exercise therapy; Osteoarthritis; Propensity score; Rehabilitation; Thumb.