INTRODUCTION: Prehospital spinal immobilization (PSI) for patients with suspected spinal injury has been the universal standard of practice for emergency medical services (EMS) in the United States since the early 1970s. PSI research has faced numerous methodological difficulties, including an inability to evaluate whether the immobilizations being studied were carried out appropriately. The purpose of this study was to assess the quality of spinal immobilization to a long spine board in patients presenting via EMS to an emergency department (ED). METHODS: All noncritically ill patients presenting to a tertiary care academic trauma center who had been immobilized on a long spine board for EMS transport were approached for enrollment. Each subject was evaluated for the number and location of restraining straps and their degree of tightness. RESULTS: Of 50 consenting subjects, 15 (30%) had at least one unattached strap or piece of tape that should have attached their head to the board. Of 50 subjects, 44 (88%) were found to have greater than 2 cm of slack between their body and at least one strap. Among those with any straps looser than 2 cm, the average number of loose straps was 3.4. CONCLUSIONS: This study suggests that many patients are not well immobilized on arrival at the Emergency department.