Regeneration of cauda equina fibres after transsection and end-to-end suture. Light and electron microscopic study in the pig.

The regeneration of nerve fibres in pigs was studied three months after transection and end-to-end suture of the dorsal and ventral spinal nerve roots L5 and S1. Although no detailed quantitative analysis was performed, it was clearly evident that regeneration in motor roots is significantly more efficacious than in sensory roots. Probably as a reaction to Wallerian degeneration, an increase of histiocytes, fibroblasts and collagen fibrils, as well as a thickening of the sheaths was observed in the transected and sutured roots. Heterotopic glial bundles were found in the regenerated dorsal roots.