The patient is unable to stop flexion of the arm on sudden release so the arm may strike the chest and doesn't recoil to the initial position. This is most likely due to failure of timely triceps contraction. NeuroLogic Exam has been supported by a grant from the Slice of Life Development Fund at the University of Utah, the Department of Pediatrics and the Office of Education at the University of Nebraska Medical Center. Viewing the video requires installation of the free QuickTime Plug-in. Both English & Spanish audio & captions are available in this video.