Exposure to pulsed magnetic fields enhances motor recovery in cats after spinal cord injury.

Abstract

Animal model study of eight healthy commercial cats was conducted. To determine whether pulsed electromagnetic field (PMF) stimulation results in improvement of function after contusive spinal cord injury in cats. PMF stimulation has been shown to enhance nerve growth, regeneration, and functional recovery of peripheral nerves. Little research has been performed examining the effects of PMF stimulation on the central nervous system and no studies of PMF effects on in vivo spinal cord injury (SCI) models have been reported. PMF stimulation was noninvasively applied for up to 12 weeks to the midthoracic spine of cats with acute contusive spinal cord injury. The injury was produced using a weight-drop apparatus. Motor functions were evaluated with the modified Tarlov assessment scale. Morphologic analyses of the injury sites and somatosensory-evoked potential measurements were conducted to compare results between PMF-stimulated and control groups. There was a significant difference in locomotor recovery between the PMF-stimulated and control groups. Although not statistically significant, PMF-stimulated spinal cords demonstrated greater sparing of peripheral white matter and smaller lesion volumes compared to controls. Somatosensory-evoked potential measurements indicated that the PMF-stimulated group had better recovery of preinjury waveforms than the control group; however, this observation also was not statistically significant because of the small sample size. This preliminary study indicates that pulsed magnetic fields may have beneficial effects on motor function recovery and lesion volume size after acute spinal cord injury.