Sensory nerve function and auto-mutilation after reconstruction of various gap lengths with nerve guides and autologous nerve grafts.

The aim of this study was to evaluate sensory nerve recovery and auto-mutilation after reconstruction of various lengths of nerve gaps in the sciatic nerve of the rat, using different techniques. Group 4, in which the longest nerve gap (15 mm) was reconstructed with a thin-walled p(DL-lactide-gamma-caprolactone) nerve guide filled with modified denatured muscle tissue, showed the best results in the electro-stimulation tests and signs of severe auto-mutilation were not observed. Even in the control group, in which a 10 mm nerve gap was left open, in two of the five rats improvement of the sensory nerve function was observed, which was caused by re-innervation of the sciatic nerve and not by expansion of the neighboring saphenous nerve. It is hypothesized that a better quality of nerve reconstruction/guidance channel/support results in faster regeneration and hence re-innervation, thereby, preventing auto-mutilation. A thin red glabrous skin, anhydrosis (dryness of the skin), short nails and edema were interpreted as signs of autonomic dysfunction.