Sage Journals: Discover world-class research

Abstract

Firefighters’ helmets were linked to increased neck muscle strain and potential cervical spine degeneration due primarily to their weight and inertial properties. This study investigated how helmet mass, center of mass (COM), and moment of inertia (MOI) affect cervical joint reaction forces (JRFs) during head-neck flexion-extension (FE) movements. Five male and five female firefighters performed dynamic flexion-extension and static flexion and extension tasks under three conditions: no-helmet, a US-style helmet, and a European (EU) helmet. Subject-specific OpenSim models were developed to estimate three-dimensional cervical JRFs from C0–C1 to C7–T1. Results showed that the US helmet, despite being lighter, induced higher compressive and shear forces than the EU helmet due to its superiorly shifted COM and higher MOI. These findings highlight the role of lowering the COM on the helmet design to reduce spinal loading and the injury risk. Future studies should incorporate lateral and rotational movements and sex-specific modeling.

Keywords

OpenSim cervical spine reaction forces firefighter helmet cervical injury

Get full access to this article

View all access options for this article.

References

Abolfotouh

S. M.

Alnori

Choma

Moore

Abolfotouh

M. A.

(2024). Epidemiology of work-related neck pain among spine surgeons. Global Spine Journal, 14(5), 1515–1523.

Adams

M. A.

Freeman

B. J.

Morrison

H. P.

Nelson

I. W.

Dolan

(2000). Mechanical initiation of intervertebral disc degeneration. Spine, 25(13), 1625–1636.

Adams

M. A.

Hutton

(1985). Gradual disc prolapse. Spine, 10(6), 524–531.

Barrett

J. M.

Healey

L. A.

Fischer

S. L.

Callaghan

J. P.

(2024). Cervical spine motion requirements from night vision goggles may play a greater role in chronic neck pain than helmet mass properties. Human Factors, 66(2), 363–376.

Barrett

J. M.

McKinnon

C. D.

Dickerson

C. R.

Laing

A. C.

Callaghan

J. P.

(2022). Posture and helmet configuration effects on joint reaction loads in the middle cervical spine. Aerospace Medicine and Human Performance, 93(5), 458–466.

Campbell

Molis

J. L.

(2022). Firefighter injuries on the fireground. National Fire Protection Association (NFPA).

Cazzola

Holsgrove

T. P.

Preatoni

Gill

H. S.

Trewartha

(2017). Cervical spine injuries: A whole-body musculoskeletal model for the analysis of spinal loading. PLoS One, 12(1), e0169329.

Mathys

Ferguson

(2012). Simulation of the effects of different pilot helmets on neck loading during air combat. Journal of Biomechanics, 45(14), 2362–2367.

McGill

S. M.

(1997). The biomechanics of low back injury: implications on current practice in industry and the clinic. Journal of Biomechanics, 30(5), 465–475.

10.

Mortensen

J. D.

Vasavada

A. N.

Merryweather

A. S.

(2018). The inclusion of hyoid muscles improve moment generating capacity and dynamic simulations in musculoskeletal models of the head and neck. PLoS One, 13(6), e0199912.

11.

Motiwale

Subramani

Kraft

R. H.

Zhou

(2018). A non-linear multiaxial fatigue damage model for the cervical intervertebral disc annulus. Advances in Mechanical Engineering, 10(6), 1687814018779494.

12.

Newman

Riches

Mara

Spratford

(2022). The effect of helmet mass and aircraft acceleration on cervical spine loads during typical fast jet aircraft pilot head motions. Journal of Science and Medicine in Sport, 25(10), 855–860.

13.

Paulon

G. M.

Sudeesh

Wei

Chowdhury

S. K.

(2024). Firefighter helmets and cervical intervertebral kinematics: An OpenSim-based biomechanical study. Journal of Biomechanics, 163, 112364.

14.

Solomonow

Zhou

B.-H.

Baratta

Harris

(1999). Biomechanics of increased exposure to lumbar injury caused by cyclic loading: Part 1. Loss of reflexive muscular stabilization. Spine, 24(23), 2426–2434.

15.

Valente

Crimi

Vanella

Schileo

Taddei

(2017). NmsBuilder: Freeware to create subject-specific musculoskeletal models for OpenSim. Computer Methods and Programs in Biomedicine, 152, 85–92.

16.

Vasavada

A. N.

Danaraj

Siegmund

G. P.

(2008). Head and neck anthropometry, vertebral geometry and neck strength in height-matched men and women. Journal of Biomechanics, 41(1), 114–121.

17.

Vicon. (2023). Plug-in gait reference guide. Vicon Motion Systems.

18.

Yin

N. H.

Giulio

I. D.

Hodkinson

P. D.

Formenti

Pollock

R. D.

(2024). Sex differences in cervical disc height and neck muscle activation during manipulation of external load from helmets. Experimental Physiology, 109(10), 1728–1738.

Static Optimization-Based Cervical Spine Load Estimation to Evaluate Firefighter Helmet Effects

Abstract

Keywords

Get full access to this article

References