Mid- To Long-Term Results of Radiocapitellar Arthroplasty of the Elbow: A Prospective Study

The aim of the study was to analyze the results of two radiocapitellar prostheses in a large case series followed prospectively in the medium to long term and to discuss the indications and results of each prosthesis. In the last two decades, radiocapitellar arthroplasty (RCA) has been introduced to treat post-traumatic and degenerative conditions of the elbow. Two implants were used: the resurfacing replacement for the lateral compartment of the joint, called the "Lateral Resurfacing Elbow (LRE), and the “Uni-Elbow Radio Capitellum Implant” (UNI-E). There are few case series on RCA, and the majority of those that do exist are based on small groups of patients and a short- to medium-term follow-up. Thirty-one patients with a mean age of 54 years were analyzed. There were 9 primary and 17 cases of post-traumatic osteoarthritis, 3 of capitellum necrosis and 2 of acute fractures. Seventeen Lateral Resurfacing Elbow (LRE) and 14 Uni-Elbow Radio-Capitellum Implant (UNI-E) arthroplasties were performed. Pre- and postoperative evaluations were based on the Mayo Elbow Performance Score (MEPS), the Quick Disabilities of the Arm, Shoulder and Hand score (Quick-DASH) and the modified American Shoulder Elbow Surgeons score (m-ASES). The mean follow-up was 6.8 years (3.8 to 11.5). Overall, the MEPS, m-ASES and Quick DASH scores improved significantly by 50, 55 and 54 points, respectively. No differences emerged between the two implants, with the exception of worse preoperative pronation-supination values in the UNI-E group; at the last follow-up, pronation was better in the LRE group. Radiocapitellar arthroplasty yielded a significant and long-lasting improvement in elbow function with a 100% implant survival. The LRE appears to be more suitable for primary osteoarthritis while the UNI-E appears to be more suitable for post-traumatic conditions associated with radial head deformities or capitellum necrosis.