Functional Splint for Osteoarthritis of the Trapeziometacarpal Joint

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.