Forty participants were enrolled in a randomized, controlled clinical trial to evaluate the effectiveness of a functional thumb splint for trapeziometacarpal OA in the dominant hand.

Treatment, Randomized, Single Blind, Placebo Control, Parallel Assignment, Efficacy Study

Inclusion Criteria:

• clinical and radiological diagnosis of idiopathic Grade II and III OA of the TMC joint on the dominant hand;
• either gender;
• over 40 years of age;
• pain in the base of the thumb of the dominant hand greater than three and less than or equal to seven on the 0 to 10-cm visual analogue scale (VAS) for pain.

Exclusion Criteria:

• severe deformities of the dominant hand that did not allow gripping between the first, second and third fingers;
• deformities of distal interphalangeal joint;
• use of a splint on the thumb in the previous six months;
• surgery on the hand under study in the previous six months or scheduled in the upcoming six months;
• allergy to the splint material;
• incapacity to respond to the questionnaire and perform the tests;
• geographic inaccessibility;
• injections in the hand under study in the previous six months;
• other associated diseases such as carpal tunnel syndrome, fractures in the carpus, tendonitis, chronic inflammatory arthropathy;
• alterations in the use of anti-inflammatory medication and analgesics in the previous three months.