After big loos of substances of peripheral nerves, in order to connect proximal with distal stump, it is possible to use, in alternative to autologous grafting, different kind of conduits. The chitosan conduit and the muscle in vein technique showed very good results in pre clinical and clinical settings. We compared in this study the efficacy of empty chitosan conduit versus chitosan conduit enriched with fresh muscle fibbers (MIT) to improve peripheral nerve regeneration. The median nerve of rat was repaired by means of empty chitosan conduit or MIT (nerve gam 6mm, conduit length 10 mm). As control group we used auto grafting technique. We performed analysis at short term (7,14,28 days) and at long term (12 weeks) in order to register bimolecular modification ( Bimolecular analysis showed that muscle fibbers produced and released Neuregulin1, needed for regeneration and activity of Schwann cells. Otherwise also the autograft product Neuregulin1, instead no production was observed in empty conduit. So muscle fibbers compensate this fact. Morphological analysis showed that the first myelinc fibbers appear in MIT after 14 days, but not in empty tube. The results of our work are very interesting because can merge the easiness of the implantation of chitosan tube and the efficacy of fresh muscle fibbers, as previously demonstrated by muscle in vein technique. From a clinical point of view this procedure could be an alternative to auto grafting that is nowadays the gold standard for nerve repair, but present soma disadvantages.
Scar tissue formation between nerve and surrounding muscle is one of the most undesired occurrence in nerve surgery In order to prevent scar tissue apposition after surgery, a lot of biocompatible products have been developed and tested first of all on animal models and then in surgical practice. we tested the efficacy of a CMC-PEO gel in reduction of perineural scar tissue formation in a mice model and in a small group of patients We performed surgical procedures on 26 male mices The animals were randomized into three groups. In each group the muscular bed of sciatic nerve was burned with diathermocoagulator. In treated group we applied the tested gel in order to reduce the post surgical scar. After 3 weeks the strenght of the scar was studied using a specific tool. Also histologic analysis was performed. We also reported the results of CMC-PEO gel on 8 patients who underwent surgical decompression of peripheral nerves affected by recurrent compressive syndrome The biomechanical analysis showed that gel application strongly reduces scar tissue. The difference between not treated and treated group was statistically significative. The histological analysis confirmed this data showing a cleavage plan between scar tissue and sciatic nerve. In patients we monitored VAS pre and post operative and we described reduction from 8 to 1 in 6 patients and from 6 to 1 in two patients. In conclusion, our study proves the efficacy in animal models of Dynavisc in scar tissue formation prevention and discloses the absolute security and biocompatibility of this products. Moreover also the small sample of patients showed the safety of this product on human, and proved its efficacy on recurrent nerve compression syndrome associated with neurolysis.
