Introduction: The Universal 2 total wrist system (KMI, San Diego) has been designed for completely uncemented implantation when indicated by the surgeon. The prosthesis has a stable articulation that allows immediate active motion through a functional arc. Minimal bone is resected and the distal ulna can be retained when suitable. The purpose of this prospective study was to review the early results of this prosthesis, with emphasis on complications, functional outcome, and implant fixation.

Materials and Methods: The first 25 patients treated for severe wrist arthritis by three surgeons using the Universal 2 prosthesis were reviewed. 20 patients had rheumatoid arthritis, 2 post-traumatic arthritis, and 3 osteoarthritis. 20 were women and 5 were men. All prostheses were implanted uncemented. The distal ulna was preserved in 7 patients. Minimum follow-up was one year, with a range of 12 to 20 months. Average patient age was 55 years, with a range of 18 to 75. Pre and serial postoperative assessments included outcome surveys (DASH, PRWE, Arthritis Impact, and study-specific), range of motion measurements, functional assessments including the Jebsen’s test, and standard radiographs.

Results: Average postoperative flexion was 38°, extension 32°, radial deviation 7°, ulnar deviation 12°, pronation 80°, and supination 73°. Pain relief was rated very good by all patients but mild ulnar sided wrist discomfort persisted in 5. Pain relief and motion often did not reach their maximums for six months. There were no major peri-operative complications, including fractures, infections or prosthetic dislocations, and there were no revisions. Average DASH scores improved 20% and PRWE scores improved 35%. Functional performance was retained or improved in all cases. No cases showed implant subsidence or loosening on radiographs.

Summary: The Universal 2 prosthesis has shown excellent early results, providing very good pain relief, a functional arc of motion, and improved hand function. Its uncemented fixation has been reliable in patients performing low to moderately demanding activities.