Postoperative Therapy After Interposition Arthroplasty in CMC1

In this randomized controlled trial the investigators want to investigate whether early versus late mobilisation after surgery in the first carpometacarpal joint (CMC1) leads to a faster recovery of hand function. The investigators also want to explore patients' satisfaction with the two different treatment regimes. The participants in the control group will receive the standard treatment at Diakonhjemmet hospital: immobilisation of the thumb in a splint for six weeks. The participants in the intervention group will use a soft splint for six weeks, but will be instructed to remove the splint daily to perform exercises for the thumb. A total of 70 patients will be included in the study.