First carpometacarpal joint arthritis is a common condition encountered by hand surgeons. Traditionally, surgical approaches have included arthrodesis, trapeziectomy or reconstructive arthroplasty techniques. Previously, we described a technique for arthroscopic debridement and interposition arthroplasty of the first carpometacarpal joint. Patients with Eaton stages II and III symptomatic first carpometacarpal joint arthritis recalcitrant to >6 months of non-operative therapy underwent arthroscopic debridement of the first carpometacarpal joint with interposition of an acellular dermal matrix allograft (GRAFTJACKET). In this paper, we describe outcomes following this procedure. Postoperatively, all patients reported symptomatic relief and 94% stated that they were partially, or completely, satisfied. More than 70% of patients reported no to mild difficulty in performing activities of daily living (average grip strength = 18.5 kg, pinch strength = 3.9kg). Complications were minimal. Outcomes from this study compare favourably to those of other series, demonstrating that this technique is a viable option for treatment of Eaton stages II and III first carpometacarpal arthritis.