Biomechanical analysis of experimental spinal cord injury and functional loss.

Spinal cord injury was studied using a drop-weight technique in a rat model. A constant weight of 10 g was dropped from 2.5, 5.0 and 17.5 cm heights. The trauma delivered was quantified by biomechanical parameters of weight drop height, maximum force, and impulse, while the functional deficit produced by injury was quantified in terms of the maximum inclined plane score, hindlimb motor score, and combined behavioral score. Highly significant (P = 0.0001) relationships were found within the biomechanical parameters of trauma as well as between the trauma and the functional parameters at 4 weeks after injury. The impulse was found to be the best predictor of the functional loss (r = 0.79, P = 0.0001).