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bioRxiv · 10.1101/2022.02.18.481008

Hyperflexion is unlikely to be the primary cervical spine injury mechanism in accidental head-on rugby tackling

Silvestros, P.·Preatoni, E.·Gill, H. S.·Cazzola, D.
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Abstract

In Rugby a high proportion of catastrophic cervical spine injuries occur during tackling. In the injury prevention literature, there is still an open debate on the injury mechanisms related to such injuries, with hyperflexion and buckling being under scrutiny. The aims of this study were to determine the primary cervical spine injury mechanism during head-on rugby tackling, and evaluate the effect of tackling technique on cervical spine intervertebral loading. We conducted an in silico study to examine the dynamic response of the cervical spine under loading conditions representative of accidental head-on rugby tackles by using a subject-specific musculoskeletal model of a rugby player. The computer simulations were driven by experimental in vivo data of an academy rugby player tackling a punchbag, and in vitro data of head-first impacts using a dummy head. Results showed that: i) the earlier generation of high compression and anterior shear loads with low values of flexion moments provides evidence that hyperflexion is unlikely to be the primary injury mechanism in the sub-axial cervical spine (C3-C7) during central and posterior head impact locations; ii) a higher degree of neck flexion at impact poses the cervical spine in a more hazardous position. These findings provide objective evidence to inform injury prevention strategies or rugby law changes, with the final view of improving the safety of the game of rugby.

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Silvestros, P., Preatoni, E., Gill, H. S., Cazzola, D.. 2022-02-20. Hyperflexion is unlikely to be the primary cervical spine injury mechanism in accidental head-on rugby tackling. https://doi.org/10.1101/2022.02.18.481008

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