SAFETYLIT WEEKLY UPDATE

We compile citations and summaries of about 400 new articles every week.
RSS Feed

HELP: Tutorials | FAQ
CONTACT US: Contact info

Search Results

Journal Article

Citation

Kent RW, Bass CR, Woods W, Sherwood CP, Madeley NJ, Salzar R, Kitagawa Y. Traffic Injury Prev. 2003; 4(4): 297-314.

Affiliation

University of Virginia, Charlottesville, Virginia, USA. rwk3c@virginia.edu

Copyright

(Copyright © 2003, Informa - Taylor and Francis Group)

DOI

unavailable

PMID

14630579

Abstract

Thoracic deformation under an applied load is an

established indicator of injury risk, but the force required to achieve an

injurious level of deformation currently is not understood adequately. This

article evaluates how two potentially important factors, loading condition and

muscle tensing, affect the structural response of the dynamically loaded thorax.

Structural models of two human cadaver thoraxes and two porcine thoraxes were

used to quantify the effects. The human cadavers, which represent anthropometric

extremes, were subjected to anterior loading from (1) a 5.1-cm-wide belt

oriented diagonally (i.e., seatbelt-like loading), (2) a 15.2-cm-diameter rigid

hub, and (3) a 20.3-cm-wide belt oriented laterally (i.e., a distributed load).

A structural model having the mathematical formulation of a quasilinear

viscoelastic material model was used to model the elastic and viscous response,

with ramp-hold tests used to determine the model coefficients. The effect of

thoracic musculature was assessed using similar ramp-hold tests on the porcine

subjects, each with and without forced muscle contraction. Even maximally

contracted thoracic musculature is shown to have a minimal effect on the

response, with similar elastic and viscous characteristics exhibited by each

subject regardless of muscle tone. The elastic response is shown to be

approximately a factor of three stiffer for diagonal belt loading and for this

distributed loading condition than for the hub loading, indicating that the

response is influenced most by the particular anatomical structures that are

engaged and, secondarily, by the area of load application. Specifically,

shoulder involvement is shown to have a strong influence. The force relaxation

is found to be pronounced, but insensitive to the loading condition, with

long-time force relaxation coefficients (G( infinity )) in the range of 0.1 to

0.3. The findings of this study provide restraint-specific guidelines for the

force-deflection characteristics of both physical and computational thoracic

models.

NEW SEARCH


All SafetyLit records are available for automatic download to Zotero & Mendeley
Print