Neck-Injuries in Rear-End Car Collisions: Sites and Biomechanical Causes of the Injuries, Test Methods and Preventive Measures

The present work addresses the problem of neck injuries following rear-end car collisions. Biomechanics and sites of the injuries have been investigated. A new dummy neck has been developed and used to study the influence of different seat properties on occupant kinematics. Anaesthetised pigs were exposed to swift extension-flexion motions of the cervical spine. Pressure pulses in the central nervous system with magnitudes of up to about 150 mmHg (2.0 kPa) were registered during these neck motions. These pressure magnitudes seem to depend on the velocity and direction of the angular motion between adjacent vertebrae. Evans Blue dye conjugated to albumin was injected into the blood system and injuries to the spinal ganglia, particularly in the lower cervical region were found at histopathological examination. These injuries could explain many of the symptoms that are typical for patients with an AIS 1 neck injury sustained in rear-end collisions. The measured pressures are believed to be a possible cause of these injuries. In order to enable better assessment of the neck motion during staged rear-end collisions at low impact-velocities