Towards treating spinal cord injury in 'patients': one step at a time

Abstract

For many years, there has been an expectation that developments in neurobiology and work on regeneration of the CNS will have early applications in the area of spinal cord injury. Now, a study by Granger et al . (2012) published in this issue of Brain reports a clinical trial in adult dogs with chronic spinal cord injury caused by an acute event, such as disk herniation. These injuries are common in veterinary practice, and studying therapeutics in this clinical population is sensible. The experimental therapeutic intervention was intraspinal transplantation of cultured autologous cells derived from the olfactory mucosa of the frontal sinus, whereas the control group received injections of cell culture medium only. The data analysis indicated a significant difference between the transplanted and control groups in forelimb–hindlimb coordination measured using kinematic analysis of locomotion on a treadmill during partial weight support. No difference in long tract functional recovery was detected between the groups using motor- and somatosensory-evoked potentials. This veterinary study has relevance to human clinical trial designs in several ways. For example, as the authors point out, the external validity is higher with this heterogeneous dog population than with a genetically homogeneous laboratory animal study. In addition, the cell therapy study had a relevant control group that was injected with cell culture medium and was blinded. Careful reading of the study discloses several interesting points for consideration. It is not clear from the inclusion and exclusion criteria whether the enrolled dogs had undergone decompressive surgery at the time of their index paraplegia. Lack of surgical decompression might mitigate against recovery independent of a transplant effect. At study entry, there was a clinical examination, MRI, measurement of somatosensory-evoked potentials and motor-evoked potentials and urodynamic evaluation. The results of the MRI are not described. Motor-evoked potentials were recorded from one lower …