Short-term effects of two different orthosis in pain relief in patient with CMC joint OA. A prospective, randomized controlled trial.

Abstract

Study design Randomized controlled trial. Introduction Carpometacarpal (CMC) joint osteoarthritis critically impacts activities of daily living. Pain, is the main reason for a consultation to the hand therapy clinic as described in the literature and conservative treatment, typically an orthosis, is the first intervention of choice. A thumb orthosis is a specific non-operative palliative treatment for carpometacarpal joint osteoarthritis for improving function and comfort. A variety of thumb orthoses are described in the literature, but there is no supporting evidence highlighting the use of a specific orthotic design for a short time effect on pain and function. Purpose of the study The study was conducted to compare the short term effect of two different thumb CMC orthoses on pain reduction as a primary outcome and improved hand function as a secondary outcome. Methods A total of 66 subjects were included in the study. One group of 33 patients received a Hybrid orthosis, immobilizing only the CMC joint, and the other group of 33 patients received a thumb orthosis called the “whale” which immobilizes the CMC and metacarpophalangeal (MP) joints. Both orthotic designs were custom fabricated for each patient. Outcomes measures included the Visual Analog Scale (VAS) for pain and the Quick DASH (Spanish version) for function.

Results Differences in pain scores and functional scores were found in both groups after the one-week washout period compared with baseline, but did not differ significantly between the two groups. Outcome for functional score demonstrated both clinically and statistically significant differences between the baseline and 1 week for outcome score for the both groups (p=, 001). With respect to pain intensity, the mean pain score decreased from 7, 69 to 5, 51 for the CMC orthosis (p=, 001) and from 7, 78 to 5, 45 for the CMC/ MP “whale orthosis” (p=, 001). Conclusion The present study adds to our therapeutic knowledge base regarding the benefits of two different thumb orthotic designs on pain reduction and functional improvement in the first week using orthoses as an exclusive conservative treatment.