End-to-Side Nerve Repair: Current Concepts and Future Perspectives.

Area of Science:

• Neurosurgery
• Regenerative Medicine
• Microsurgery

Background:

• Peripheral nerve injuries present significant challenges for reconstructive surgeons.
• End-to-side (ETS) neurorrhaphy is a technique for nerve repair lacking a usable proximal nerve stump.
• Historically, ETS nerve repair was explored, then largely abandoned, before being revisited.

Purpose of the Study:

• To review experimental and clinical investigations of ETS nerve repair.
• To identify unanswered questions and advocate for further basic research in ETS nerve repair.

Main Methods:

• Review of historical and contemporary experimental studies on ETS nerve repair.
• Analysis of clinical case studies and applications of ETS neurorrhaphy.
• Examination of proposed mechanisms for axonal regeneration in ETS repair (terminal and collateral sprouting).

Main Results:

• ETS neurorrhaphy has demonstrated clinical utility in upper extremity injuries, facial reanimation, post-tumor ablation reconstruction, and neuroma prevention.
• Two primary mechanisms, terminal and collateral sprouting, are proposed for axonal regeneration following ETS repair.
• Despite historical and recent interest, fundamental questions regarding ETS nerve repair persist.

Conclusions:

• ETS neurorrhaphy is a viable strategy for peripheral nerve reconstruction in specific clinical scenarios.
• Further basic research is crucial to fully understand and optimize ETS nerve repair techniques.
• Addressing the remaining questions will advance the application of ETS neurorrhaphy in microsurgery.