Inferior functional sensory regeneration after suture of sciatic neurotomy in newborns compared with mature rats.

It is generally believed that nerve injuries in children regenerate better than those which occur in adults. However, there are no functional experimental studies that support this belief. This study evaluates the functional regeneration of polymodal C-fibres after nerve regeneration in newborn and mature rats 3 months after unilateral sciatic nerve neurotomy and suture. The distribution of polymodal C-fibres was tested by measuring the Evans blue-stained area in the skin after antidromic nerve stimulation. In the newborn group of regenerated animals showed that functional C-fibres were present in a significantly (P < 0.05) smaller area than found in the adult group. We conclude that the functional regeneration of C-fibres is superior in mature rats compared with newborns, 3 months after regeneration.