9. Impact Injuries of the Thoracolumbar Spine

Impact injuries to the thoracolumbar spine are rare in automotive crashes. They take the form of vertebral body wedge fractures and, at times, burst fractures, particularly among the elderly. The cause is not vertical acceleration of the vehicle but is instead the straightening effect of the thoracic spine when the shoulder belt restraint is used. However, impact injuries due to vertical acceleration do occur in other environments, especially in the military environment. One of the first military problems is that of seat ejection – the emergency exit of a pilot from a disabled military jet aircraft. Some pilots sustain anterior wedge fractures of the thoracolumbar spine due to the 20 g acceleration of the seat. The injury was first recognized by the Luftwaffe or the German air force during World War II and was studied intensely in Britain and the USA for several decades after the war. The current problem is injury to the spine, pelvis, and lower extremities sustained by mounted soldiers whose vehicle they are riding in encounters an improvised explosive device. In this book, the seat ejection problem will be addressed, but blast-related injuries will not. Civilian injuries to the thoracolumbar spine due to falls also produce similar injuries. Falling from a height and landing on one’s buttocks generate wedge-type vertebral injuries. Fracture-dislocations can occur in more severe impacts. Such injuries are catastrophic because they can result in damage to the spinal cord and paralysis from the waist down. Ejection from a moving automobile or rollover of a vehicle can also cause these injuries.