Polyethylene glycol-induced motor recovery after total spinal transection in rats.

Aims: Despite more than a century of research, spinal paralysis remains untreatable via biological means. A new understanding of spinal cord physiology and the introduction of membrane fusogens have provided new hope that a biological cure may soon become available. However, proof is needed from adequately powered animal studies. Methods and results: Two groups of rats (n=9, study group, n=6 controls) were submitted to complete transection of the dorsal cord at T10. The animals were randomized to receive either saline or polyethylene glycol (PEG) in situ. After 4 weeks, the treated group had recovered ambulation vs none in the control group (BBB scores; P=.0145). One control died. All animals were studied with somatosensory-evoked potentials (SSEP) and diffusion tensor imaging (DTI). SSEP recovered postoperatively only in PEG-treated rats. At study end, DTI showed disappearance of the transection gap in the treated animals vs an enduring gap in controls (fractional anisotropy/FA at level: P=.0008). Conclusions: We show for the first time in an adequately powered study that the paralysis attendant to a complete transection of the spinal cord can be reversed. This opens the path to a severance-reapposition cure of spinal paralysis, in which the injured segment is excised and the two stumps approximated after vertebrectomy/diskectomies.