Clinical and radiographic follow-up study of the elbow and shoulder in 19 children and adults with Apert syndrome demonstrates that these two joints are affected to varying degrees. Shoulder motion is never normal and may be quite restricted, with the progression of growth abnormalities of the proximal humerus and accompanying glenoid dysplasia. Limitation of abduction is secondary to an impingement of an overgrown greater tuberosity upon the acromion. Clinically, these children appear to have anterior subluxations. Elbow motion is limited in a much smaller percentage of patients and was not a significant problem unless elbow fusion occurred. A radiocapitellar dysplasia was associated with a mean 30-degree extension loss in 7 of 19 patients. Two patients had no elbow motion.