Ten cadaveric human upper cervical spine specimens were subjected to a high speed axial impact. Injuries to the atlas consisted of bursting fractures, ruptures of the transverse ligament, and posterior arch fracture. The major soft tissue injury involved the transverse ligament:​ 5 bony avulsions and 3 mid-substance tears. CT examination clearly demonstrated the sites of fracture and bony avulsions of the transverse ligament. The best diagnostic tool for function of the transverse ligament was the Atlanto-Dental Interval on x-ray. Our in vitro atlas injury model gives useful information for clinical diagnosis and treatment.