Cemented bipolar radial head arthroplasty: midterm follow-up results

Background: Theoretical advantages of bipolar over monopolar radial head arthroplasty include better accommodation of radiocapitellar malalignment, reduction of capitellar abrasion, and reduction of stress at the bone-to-cement and cement-to-implant interfaces. Our purpose was to report the midterm results of cemented bipolar radial head arthroplasty. Methods: Twenty-five patients were treated by cemented bipolar radial head arthroplasty for acute fracture of the radial head, earlier treatment that had failed, or posttraumatic sequelae. One patient refused follow-up after surgery. Results are presented for the remaining 24 patients. Results: At a mean follow-up of 50 months (range, 24-72 months), 1 prosthesis (4%) had been removed 2 years after implantation for dissociation of the prosthesis due to failure of the snap-on mechanism. There were 2 (8%) additional radiologic failures in the subluxated position: 1 prosthesis due to malalignment of the radius onto the capitellum and another due to ulnohumeral erosion. The average flexion-extension arc was 129 degrees (range, 80 degrees-140 degrees), and the average pronation-supination arc was 131 degrees (range, 40 degrees-180 degrees). According to the Mayo Elbow Performance Score, the combined excellent and good results accounted for 83%. In 8 patients, the bipolar design compensated for radiocapitellar malalignment. Conclusions: The overall midterm outcome of this series of 25 cemented bipolar radial head arthroplasties can be considered favorable. There was 1 (4%) revision and 2 (8%) additional radiologic failures. The bipolar design was able to compensate for radiocapitellar malalignment. We suggest considering a cemented bipolar radial head prosthesis in case of concerns about radiocapitellar alignment. (C) 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.