Thumb carpometacarpal osteoarthritis is common and may cause severe pain and functional limitation. Trapeziectomy is widely used, whereas prosthetic arthroplasty may offer faster early recovery. However, detailed information on early postoperative and long-term radiological outcomes remains limited.
This is a single-centre, blinded randomised controlled trial at Sahlgrenska University Hospital, Gothenburg, Sweden. Adults aged 18-69 years with symptomatic thumb carpometacarpal osteoarthritis (Eaton grade 2-3) refractory to at least 3 months of non-operative treatment will be randomised 1:1 to trapeziometacarpal prosthetic arthroplasty or trapeziectomy. The primary outcome is day-by-day pain (registration on a numeric rating scale NRS, 0-10). Secondary outcomes include day-by-day analgesic consumption for 90 days, orthosis use after cast removal, patient-reported function (HQ-8, QuickDASH, and Nelson score) at 30, 45, 60, 75 and 90 days, assessor-measured range of motion and strength at 45 and 90 days, and long-term clinical follow-up at 6 months and 1, 2, 5 and 10 years. Cone beam computed tomography will be obtained in the arthroplasty group at 1 week postoperatively as reference and at 6 months and 1, 2, 5 and 10 years to assess implant position, migration and loosening. The target sample size is 64 participants (32 per group), providing 95% power to detect a 1-point between-group difference on the pain scale. Analyses will follow the intention-to-treat principle.