Nguyen JC, et al. - In this retrospective study of 41 children with 43 osteochondritis dissecans (OCD) lesions of the elbow who underwent an MRI examination between April 1, 2010, and May 31, 2018, experts examined the performance of MRI criteria for prognosticating instability of OCD lesions of the elbow in children. A total of 20 stable and 23 unstable OCD lesions were there. In unstable vs stable OCD lesions, an osteochondral defect, intraarticular body, overlying cartilage changes, subchondral bone plate disruption, and hyperintense rim were significantly more prevalent. Nevertheless, for OCD instability, only osteochondral defect and intraarticular body were 100% specific. No important variation between stable and unstable OCD lesions in the presence of joint effusion, cysts, marginal sclerosis, or perilesional bone marrow edema was found. Hence, MRI findings of OCD instability of the elbow involve an osteochondral defect, intraarticular body, overlying cartilage changes, subchondral bone disruption, and rim of high signal intensity on T2-weighted MR images.