Elbow stiffness is a well-recognized complication following elbow trauma, but little information is available regarding the surgical treatment of elbow stiffness in children and adolescents. This article presents the results of open arthrolysis with twin incisions and a hinged external fixator to treat severe elbow contracture in children and adolescents. Twenty-one patients (mean age, 14.9 years; range, 7-19 years) were evaluated. All patients underwent surgery using a hinged external fixator and a combined mediolateral approach to address the elbow contracture. Mayo elbow score and range of motion (ROM) were measured preoperatively and at 3, 12, and 24 months postoperatively. All but 1 patient achieved a functional ROM of 100 degrees. Preoperatively, mean flexion was 70.2 degrees (range, 30 degrees-100 degrees), extension was 42.6 degrees (range, 0 degrees-80 degrees), and total ROM was 28.5 degrees (range, 0 degrees to 80 degrees); postoperatively, mean flexion improved to 122.8 degrees (range, 90 degrees-140 degrees), extension to 10 degrees (range, 0 degrees-30 degrees), and total ROM to 114.5 degrees (range, 60 degrees-140 degrees). The Mayo elbow score improved from a mean of 48 points (range, 35-65 points) to 90 points (range, 75-100 points), and 9 patients had excellent results, 7 had good results, 4 had fair results, and 1 had a poor result. No significant differences existed between postoperative measurements at 3, 12, and 24 months. No pin-tract infections or deep infections occurred, and no vascular or neurological complications were noted. Surgical treatment of elbow stiffness using a hinged external fixator and open arthrolysis is an effective procedure in children and adolescents.