Comparison of a distal end-to-side neurorrhaphy with a proximal-distal end-to-side neurorrhaphy: in a rat model.

Background: Peripheral nerve injuries have severe consequences on quality of life, especially in cases with extensive or old injuries when standard nerve repair is impossible and proposed repair methods are not completely satisfactory. Terminolateral neurorrhaphy is a practical and advantageous technique for nerve repair; therefore, we developed a nerve function study to evaluate advantages of proximal stump coaptation in end-to-side nerve repair method.

Methods: Three experimental groups were studied: In group A, the proximal and distal stumps of the transected peroneal nerve were sutured to the posterior tibialis nerve in left side and right side left intact; in group B, a classic end-to-side neurorrhaphy was performed; and group C was without neurorrhaphy as the control group. Five months later, visual functional assessment of sciatic nerves was performed to assess the statistic sciatic index (SSI).

Results: The surgical procedures caused an ipsilateral rehabilitation in groups A and B compared with the control group (p < 0.05). Although comparison of intermediate toe spread factor of distal-proximal nerve repair and distal nerve repair (DNR) was not statistically significant, toe spread factor and subsequently SSI comparisons showed significant statistical difference (p < 0.05).

Discussion: Contribution of proximal nerve stump to DNR improved functional recovery of motor neurons in an end-to-side cooptation method in rat lower extremity. Some of possible explanations for positive results could be the presence of more neuroattractive substances and use of donor nerve epineurium as a neuropermissive bridge for the regenerated axons.