End-to-End Versus End-to-Side Motor and Sensory Neurorrhaphy in the Repair of the Acute Muscle Denervation

The aim of this study was to experimentally compare end-to-end and end-to-side neurorrhaphy in perineural window model after motor nerve lesion, evaluating which one was the most effective to preserve nerves. Also, differences in motor and sensorial nerve regeneration were tested to verify differences in nerve regeneration. A total of 20 adult male Wistar rats were randomly assigned to 5 groups, and, in each one, a different treatment was performed: besides the control group, and end-to-end or end-to-side graft with motor or sensorial nerves was performed. Silastic sheet was used as a mechanical barrier to prevent innervation from adjacent nerves. After 16 weeks, the specimens were histologically assessed and wet weight was evaluated as a direct parameter of atrophy. The end-to-end neurorrhaphy group presented the best results in terms of mass preservation, but it did not differ significantly from the control group. Motor nerves presented similar results in muscular atrophy. The end-to-side neurorrhaphy group with sensory nerve as donor showed the worst results. The use of sensory nerves to preserve skeletal muscle trophism is not justified, since, according to our model, it affects 50% to 80% of the muscle mass in a period of 16 weeks. End-to-side neurorrhaphy was demonstrated to be an option for re-enervation of a nerve-deprived motor muscle in selected cases.