BACKGROUND Between 1994 and 1999, 837 flexion-extension cervical spine films (F/E) were ordered as part of a protocol to evaluate cervical stability in blunt trauma victims, particularly obtunded patients with otherwise normal films. After 5 years' experience with this protocol, a review of its efficiency and cost-effectiveness was performed. METHODS The radiology reports and charts were reviewed for positive or suggestive F/E series. RESULTS Nearly a third of all series were inadequate to rule out instability. Only four patients were identified who had decreased admission Glasgow Coma Scale score, normal plain films and/or CT, and positive or suggestive findings on F/E. One was felt to be a false positive, and the others had minor or borderline findings; all were treated with continuation of the cervical collar. Although one patient was lost to follow-up, none of the other three required subsequent surgery or developed deformity or neurologic injury. CONCLUSIONS Flexion-extension studies were not a cost-effective part of the protocol, and they were dropped.