Primary nerve repair by muscle autografts prepared with local anesthetic.

We evaluated the usefulness of muscle autografts obtained immediately after graft preparation with lidocaine injections for primary nerve repair. The right sciatic nerve of adult Wistar rats was sectioned, and muscle grafts obtained 15 min or 24 h after lidocaine injection were used to repair a gap 1.5 cm long. Axon and fiber diameters, as well as myelin thickness, decreased to similar extents for grafts of both time intervals. The G-ratios in the distal stumps of both groups were not different from controls, indicating that regenerated axons had a proper level of myelination. The ultrastructural appearance of the neuromuscular junctions was similar to that of normal samples. These results indicate that there are no restrictions to the use of a muscle graft for primary nerve repair, immediately after lidocaine injection, since the nerve regeneration was comparable to that observed with this type of graft used 24 h after being prepared.