Patients who have juvenile rheumatoid arthritis often are seen at a very young age because of severe stiffness and pain in several joints. While total elbow replacement may be indicated in these patients, this procedure is difficult to perform because of contracture of the soft tissues and the extremely small bones and intramedullary cavities in these patients. As there is little information in the literature regarding this procedure, we attempted to learn about the long-term results by evaluating nineteen patients (twenty-four elbows) with juvenile rheumatoid arthritis who had been managed with total elbow arthroplasty. At an average of 7.4 years (range, two to fourteen years) after the operation, there was an improvement in the average Mayo elbow performance score from 31 points (range, 5 to 55 points) preoperatively to 90 points (range, 55 to 100 points). Twenty-two (96 per cent) of the twenty-three elbows available at the most recent follow-up evaluation caused little or no pain, but the improvement in the range of motion was not as reliable. The average arc of flexion improved from only 63 degrees preoperatively to 90 degrees postoperatively; the average postoperative arc of flexion began at 35 degrees, with additional flexion to 125 degrees. Examination of the four elbows that had been ankylosed before the procedure revealed an average arc of 73 degrees after the operation, and evaluation of the twenty ipsilateral wrists that were not limited by disease revealed that pronation and supination had been maintained. The average functional score improved from 9 points (range, 0 to 25 points) preoperatively to 23 points (range, 15 to 25 points) postoperatively (p < 0.001). The function of eighteen elbows (78 per cent) did not adversely affect the ability to perform activities of daily living. There were thirteen complications, including one perioperative death, that affected twelve of the twenty-four elbows. Seven of the nine early complications, including a fracture of the olecranon, subluxation of the prosthesis, stiffness of the elbow, and problems with wound-healing, led to an additional operative procedure but did not adversely affect the long-term outcome after appropriate diagnosis and treatment. Late complications (aseptic loosening, instability, and worn bushings) led to three poor results. None of the eighteen semiconstrained prostheses had radiographic evidence of loosening at the most recent follow-up evaluation. Of the twenty-three elbows that had been followed for at least two years, twelve (52 per cent) had an excellent result, eight (35 per cent) had a good result, and three (13 per cent) had a poor result.