Related Experiment Video
Updated: Jun 3, 2026

Modified Spared Nerve Injury Surgery Model of Neuropathic Pain in Mice
Published on: January 25, 2022
Forced needle advancement during needle-nerve contact in a porcine model: histological outcome
Thorsten Steinfeldt1, Sabine Poeschl, Wilhelm Nimphius
1Philipps University, Department of Anaesthesiology and Intensive Care Therapy, University Hospital Giessen-Marburg, Campus Marburg, Baldingerstrasse, 35032 Marburg, Germany. steinfeldt@gmx.de
Background:
In this study, we determined whether needle advancement during needle-nerve contact (forced needle-nerve contact) is associated with a higher risk of nerve injury compared with needle-nerve contact without needle advancement (nonforced needle-nerve contact).
Methods:
In 8 anesthetized pigs, the brachial plexus nerves underwent forced (0.15 Newton) or nonforced (0.0 Newton) needle-nerve contact without nerve penetration. The grade of nerve injury was histologically assessed using an objective score ranging from 0 (no injury) to 4 (severe injury).
Results:
Sixty-nine nerves, including controls, were examined. Histology revealed a significant difference between forced and nonforced needle-nerve contact (median [interquartile range] 3 [2-4] vs 2 [1-2]; P = 0.004). Myelin damage and intraneural hematoma occurred only after forced needle-nerve contact.
Conclusions:
The severity of structural nerve injury after needle-nerve contact was directly related to force exposure via needle advancement.

