This critical review examines the several models which have been proposed to study mechanisms of acute spinal cord injury. From a physiologic point of view, each model offers particular advantages and is useful to address specific questions about the pathophysiology. From a biomechanics point of view, however, adequate simulation of clinically occurring spinal cord injuries requires control of impact parameters which are important to injury outcome, such as amount of compression and velocity of loading. A controlled contusion technique developed by the authors provides this control and results in clinically relevant experimental injury. Both transient and maintained compression are important in determining the neurologic outcome of injury. When combined with an improved understanding of vertebral failure kinematics, neurologic injury potential may be estimated for specific vertebral loading (and failure) parameters. failure) parameters.

Beyond the biomechanics of injury, physiology must be carefully considered in the experimental protocol. The effects of alternative anesthetics, respiratory parameters, adjunctive agents and laminectomy will be reviewed. Standardized protocol would facilitate communication and comparability between laboratories. Also, the severity and outcome of clinical injury may be affected by factors such as high blood alcohol and hemorrhagic shock. Experimental study of these factors requires particular attention to baseline physiologic parameters in the experimental setting.