Splint for base-of-thumb osteoarthritis: a randomized trial

Background: Some guidelines recommend splinting for base-of-thumb osteoarthritis, despite lack of evidence of efficacy.

Objective: To assess the efficacy and acceptability of a splint for base-of-thumb osteoarthritis.

Design: Multicenter, randomized trial. Randomization was computer-generated, and allocation was concealed by faxing centralized treatment assignment to investigators at the time of enrollment. Patients and investigators were not blinded to assignment, and patients self-reported outcomes.

Setting: 2 tertiary care hospitals in France.

Patients: 112 patients (101 women) with base-of-thumb osteoarthritis.

Intervention: Custom-made neoprene splint (n = 57) or usual care (n = 55).

Measurements: Primary outcome was change in pain level assessed on a visual analogue scale (VAS) (range, 0 to 100 mm) from baseline to 1 month. Secondary outcomes were change in measures of hand disability at 1 month and change in pain level and measures of disability at 12 months. Tolerance and adherence with the splint were recorded.

Results: At 1 month, no difference in change occurred in pain level from baseline in the intervention and control groups (adjusted mean change, -10.1 vs. -10.7; between-group difference, 0.6 [95% CI, -7.9 to 9.1]; P = 0.89). Disability was assessed by the Cochin Hand Function Scale score (range, 0 to 90) or patient-perceived disability (VAS, 0 to 100 mm). At 12 months, change in pain from baseline was greater in the intervention group than in the control group (adjusted mean change, -22.2 vs. -7.9; between-group difference, -14.3 [CI, -23.4 to -5.2]; P = 0.002). The Cochin Hand Function Scale score was -1.9 versus 4.3 (between-group difference, -6.3 [CI, -10.9 to -1.7]; P = 0.008) and patient-perceived disability was -11.6 versus 1.5 (between-group difference, -13.1 [CI, -21.8 to -4.4]; P = 0.003). At 12 months, 86% of the intervention group had worn the splint for more than 5 nights a week, and no adverse effects were observed.

Limitation: Patients, health care providers, and outcome assessors were not blinded.

Conclusion: For patients with base-of-thumb osteoarthritis, wearing a splint had no effect on pain at 1 month but improved pain and disability at 12 months.

Primary funding source: Programme Hospitalier de Recherche Clinique National.