Overview of the short- and long-term quantitative outcomes following end-to-side neurorrhaphy in a rat model

• Published in: Injury Vol. 51; no. 12; pp. 2874 - 2878
• Main Authors: Zigie, Zhang, Johnson Elizabeth, O., Soucacos Panayotis, N.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01.12.2020
• Subjects: Coaptation axons; Collateral sprouting; Nerve repair; Coaptation axons; Collateral sprouting; Nerve repair
• ISSN: 0020-1383; 1879-0267
• DOI: 10.1016/j.injury.2020.02.052

•Findings indicate that end-to-side neurorrhaphy is associated with time-dependent results.•At three months, nerve conduction velocity recovered to 70%, while at 12 months it was 94% normal.•Although no differences were observed between fresh and delayed repair, the presence of a perineurotomy window significantly improved recovery.•While end-to-side coaptation had some negative impact on the donor nerve early on, donor nerve activity returned to normal at long-term follow-up.•End-to-side coaptation opens a promising perspectives in the clinical setting, especially in the cases when the proximal nerve segment unavailable, such as in facial palsy and global brachial plexus avulsion injuries. The time course of events following end-to-side nerve coaptation remains unclear. Re-innervation and effects on the donor nerve were assessed following short- and long-term end-to-side neurorrhaphy were investigated in a rat model. One hundred and our Sprague-Dawley female rats were randomized to fresh and pre degenerated repair groups with or without perineurotomy. The right peroneal nerve was sutured to the tibial nerve in an end-to-side manner. Histological and electro-physiological assessment of re-innervation and of the donor nerve was performed at two-three months and at nine-twelve months, post-operatively. The results demonstrated that end-to-side neurorrhaphy could attract axonal sprouts and successfully re-innervate the target muscles. The influence on donor nerve was minimal in late stages, although it did have early negative effect. Double labeling provided evidence that one of the mechanisms of this procedure is probably by collateral sprouting.