CC BY 4.0 · J Brachial Plex Peripher Nerve Inj 2018; 13(01): e8-e14
DOI: 10.1055/s-0038-1669405
Original Article
Georg Thieme Verlag KG Stuttgart · New York

Biomechanical Responses of Neonatal Brachial Plexus to Mechanical Stretch

Anita Singh
1   School of Engineering, Widener University, Chester, Pennsylvania, United States
,
Shania Shaji
1   School of Engineering, Widener University, Chester, Pennsylvania, United States
,
Maria Delivoria-Papadopoulos
2   Department of Pediatrics, Drexel University College of Medicine, Philadelphia, Pennsylvania, United States
,
Sriram Balasubramanian
3   School of Biomedical Engineering, Sciences and Health Systems, Drexel University, Philadelphia, Pennsylvania, United States
› Author Affiliations
Further Information

Publication History

12 February 2018

18 July 2018

Publication Date:
03 September 2018 (online)

Abstract

This study investigated the biomechanical responses of neonatal piglet brachial plexus (BP) segments—root/trunk, chord, and nerve at two different rates, 0.01 mm/second (quasistatic) and 10 mm/second (dynamic)—and compared their response to another peripheral nerve (tibial). Comparisons of mechanical responses at two different rates reported a significantly higher maximum load, maximum stress, and Young's modulus (E) values when subjected to dynamic rate. Among various BP segments, maximum stress was significantly higher in the nerve segments, followed by chord and then the root/trunk segments except no differences between chord and root/trunk segments at quasistatic rate. E values exhibited similar behavior except no differences between the chord and root/trunk segments at both rates and no differences between chord and nerve segments at quasistatic rate. No differences were observed in the strain values. When compared with the tibial nerve, only mechanical properties of BP nerves were similar to the tibial nerve. Mechanical stresses and E values reported in BP root/trunk and chord segments were significantly lower than tibial nerve at both rates. When comparing the failure pattern, at quasistatic rate, necking was observed at maximum load, before a complete rupture occurred. At dynamic rate, partial rupture at maximum load, followed by a full rupture, was observed. Occurrence of the rate-dependent failure phenomenon was highest in the root/trunk segments followed by chord and nerve segments. Differences in the maximum stress, E values, and failure pattern of BP segments confirm variability in their anatomical structure and warrant future histological studies to better understand their stretch responses.