Background: To study if patients that have a second radiograph 2 or more years after nonoperative treatment of an isolated radial head fracture have radiocapitellar osteoarthritis (RC OA). Methods: We used the database of 3 academic hospitals in one health system from 1988 to 2013 to find patients with isolated radial head fractures (no associated ligament injury or fracture) that had a second elbow radiograph after more than 2 years from the initial injury. Of 887 patients with isolated radial head fractures, 54 (6%) had an accessible second radiograph for reasons of a second injury (57%), pain (30%), or follow-up visit (13%). Two orthopedic surgeons independently classified the radial head fractures on the initial radiographs using the Broberg and Morrey modified Mason classification, and assessed the development of RC OA on the final radiograph using a binary system (yes/no). Results: Four out of 54 (7.5%) patients had RC OA, one with isolated RC arthrosis that seemed related to capitellar cartilage injury, and 3 that presented with pain and had global OA (likely primary osteoarthritis). Conclusion: With the caveat that some percentage of patients may have left our health system during the study period, about 1 in 887 patients (0.1%) returns with isolated radiocapitellar arthritis after an isolated radial head fracture, and this may relate to capitellar injury rather than attrition. Patients with isolated radial head fractures can consider post-traumatic radiocapitellar arthritis a negligible risk.