An integrated multiscale analysis of injury mechanisms in sport impacts: an application to cervical spine biomechanics in rugby union scrummaging

Research output: Chapter in Book/Report/Conference proceedingConference contribution

33 Downloads (Pure)

Abstract

Introduction and Objectives: By generating repetitive high-energy impacts (during the engagement phase) and intense
sustained loads (during the sustained push phase) under unstable conditions [1], the Rugby Union scrum has been
indicated as a possible risk factor for degenerative spinal injuries for forward players, and has been associated with
~40% of all catastrophic injuries in rugby [2]. However, little is known about how these external loading conditions
translate into internal stresses on the spinal structures. The aim of this study was to investigate the biomechanics of
cervical spine injury during rugby activities using an integrative approach: in-vivo and in-vitro experiments combined with
musculoskeletal modelling.
Methods: Three levels of analysis (Levels 1-3) were integrated. Level 1 was a biomechanical study of scrummaging (N=9
experienced rugby forwards) including motion capture (Oqus, Qualisys, Sweden), force measurement (force plates:
Kistler 92876BA, Switzerland; and instrumented scrum machine, [1]), and EMG of neck and trunk muscles (Delsys
Trigno, Delsys Inc, USA), carried out to assess the external kinematic and kinetic conditions acting on front row players.
The subsequent phases of scrummaging, initial engagament (impact and shock absorption) and sustained push, were
observed. Level 2 developed a bespoke musculoskeletal model (Rugby Model, [3]), consisting of 27 anatomical
segments, 26 joints, 78 cervical muscles, and 11 torque actuators, in OpenSim (OpenSim 3.2, SimTK, USA). The Rugby
Model was driven by the experimental data from Level 1 and was used to estimate joint dynamics, with a specific interest
in cervical joint motions and moments. Level 3 performed an in-vitro laboratory experiment to study the injury
mechanisms of porcine cervical spines subjected to impact loading conditions similar to those during scrummaging. Load
(2 load cells: SLC41/005000, RDP Electronics Ltd, UK) and deformations caused by impacts (mass of 12.86 kg dropped
from a height of 250 mm to give an impact velocity of ~2.2 m/s) were measured in a custom made impact rig, and highspeed
videos (2 Fastcam SA3, Photron Europe Ltd, UK) were used to investigate the mechanisms of injury through
digital image correlation (Vic-3D 2009.1.0, Correlated Solutions Inc, USA).
Results: Results from the biomechanical analysis confirmed that the load acting on the players, especially during the
initial engagement, was of a considerable magnitude (~2.8 kN compression force in single-player machine
scrummaging). Muscle activation patterns were affected by scrummaging conditions (e.g. machine vs. contested
scrummaging; ‘Crouch-touch-set’ vs. ‘Crouch-bind-set’ sequence) and phases of the scrum (e.g. pre-engagement vs.
engagement vs. sustaned push). For example, the activity of the erector spinae was significantly lower (in excess of 65%)
in machine scrummaging than in contested scrummaging, and the activation of sternocleidomastoid and upper trapezius
through pre-engagement and engagement were higher in the current ‘Crouch-bind-set’ technique than in the past ‘Crouchtouch-
set’ one. The computational musculoskeletal model highlighted an antiphase change in movement and loading
patterns between the upper and lower cervical levels (i.e. flexion load on the lower vertebrae and extension on the upper
vertebrae), and resulted in a “flattening” of the lordotic cervical curve during the impact phase. The present findings do
not provide direct evidence for injury mechanisms but seem in line with the patterns of injury that previous authors have
described in relation with scrum-related neck traumas [2]. The patterns of strain, load and resulting damages on the
cervical structures of the impacted porcine specimens were also similar to those clinically observed in injured players,
with the caudal vertebrae (C4-C6) more prone to damages (6 out of 8 specimens) as a consequence of the impact.
Fractures resulted from tension in the vertebral bodies due to first order buckling of the cervical spine in extension. The
mean maximum load in the cranial and caudal load cells was 5.8±2.0 kN and 6.0±2.1 kN and was reached at a time of
5.1±1.0 ms and 5.6±1.1 ms after impact, respectively.
Original languageEnglish
Title of host publicationAbstract Book of The 25th Congress of the International Society of Biomechanics
Pages10
Number of pages11
Publication statusPublished - 2015

Fingerprint

Football
Biomechanical Phenomena
Sports
Spine
Wounds and Injuries
Joints
Swine
Neck Muscles
Spinal Injuries
Muscles
Superficial Back Muscles
Touch
Torque
Switzerland
Sweden
Shock
Neck

Cite this

Preatoni, E., Cazzola, D., Holsgrove, T., Gheduzzi, S., Miles, A., Stokes, K., ... Trewartha, G. (2015). An integrated multiscale analysis of injury mechanisms in sport impacts: an application to cervical spine biomechanics in rugby union scrummaging. In Abstract Book of The 25th Congress of the International Society of Biomechanics (pp. 10). [AS-0003]

An integrated multiscale analysis of injury mechanisms in sport impacts: an application to cervical spine biomechanics in rugby union scrummaging. / Preatoni, Ezio; Cazzola, Dario; Holsgrove, Timothy; Gheduzzi, Sabina; Miles, Anthony; Stokes, Keith; Gill, Harinderjit; Trewartha, Grant.

Abstract Book of The 25th Congress of the International Society of Biomechanics. 2015. p. 10 AS-0003.

Research output: Chapter in Book/Report/Conference proceedingConference contribution

@inproceedings{d97b3c94b4444428aabe45cb15f0fa75,
title = "An integrated multiscale analysis of injury mechanisms in sport impacts: an application to cervical spine biomechanics in rugby union scrummaging",
abstract = "Introduction and Objectives: By generating repetitive high-energy impacts (during the engagement phase) and intensesustained loads (during the sustained push phase) under unstable conditions [1], the Rugby Union scrum has beenindicated as a possible risk factor for degenerative spinal injuries for forward players, and has been associated with~40{\%} of all catastrophic injuries in rugby [2]. However, little is known about how these external loading conditionstranslate into internal stresses on the spinal structures. The aim of this study was to investigate the biomechanics ofcervical spine injury during rugby activities using an integrative approach: in-vivo and in-vitro experiments combined withmusculoskeletal modelling.Methods: Three levels of analysis (Levels 1-3) were integrated. Level 1 was a biomechanical study of scrummaging (N=9experienced rugby forwards) including motion capture (Oqus, Qualisys, Sweden), force measurement (force plates:Kistler 92876BA, Switzerland; and instrumented scrum machine, [1]), and EMG of neck and trunk muscles (DelsysTrigno, Delsys Inc, USA), carried out to assess the external kinematic and kinetic conditions acting on front row players.The subsequent phases of scrummaging, initial engagament (impact and shock absorption) and sustained push, wereobserved. Level 2 developed a bespoke musculoskeletal model (Rugby Model, [3]), consisting of 27 anatomicalsegments, 26 joints, 78 cervical muscles, and 11 torque actuators, in OpenSim (OpenSim 3.2, SimTK, USA). The RugbyModel was driven by the experimental data from Level 1 and was used to estimate joint dynamics, with a specific interestin cervical joint motions and moments. Level 3 performed an in-vitro laboratory experiment to study the injurymechanisms of porcine cervical spines subjected to impact loading conditions similar to those during scrummaging. Load(2 load cells: SLC41/005000, RDP Electronics Ltd, UK) and deformations caused by impacts (mass of 12.86 kg droppedfrom a height of 250 mm to give an impact velocity of ~2.2 m/s) were measured in a custom made impact rig, and highspeedvideos (2 Fastcam SA3, Photron Europe Ltd, UK) were used to investigate the mechanisms of injury throughdigital image correlation (Vic-3D 2009.1.0, Correlated Solutions Inc, USA).Results: Results from the biomechanical analysis confirmed that the load acting on the players, especially during theinitial engagement, was of a considerable magnitude (~2.8 kN compression force in single-player machinescrummaging). Muscle activation patterns were affected by scrummaging conditions (e.g. machine vs. contestedscrummaging; ‘Crouch-touch-set’ vs. ‘Crouch-bind-set’ sequence) and phases of the scrum (e.g. pre-engagement vs.engagement vs. sustaned push). For example, the activity of the erector spinae was significantly lower (in excess of 65{\%})in machine scrummaging than in contested scrummaging, and the activation of sternocleidomastoid and upper trapeziusthrough pre-engagement and engagement were higher in the current ‘Crouch-bind-set’ technique than in the past ‘Crouchtouch-set’ one. The computational musculoskeletal model highlighted an antiphase change in movement and loadingpatterns between the upper and lower cervical levels (i.e. flexion load on the lower vertebrae and extension on the uppervertebrae), and resulted in a “flattening” of the lordotic cervical curve during the impact phase. The present findings donot provide direct evidence for injury mechanisms but seem in line with the patterns of injury that previous authors havedescribed in relation with scrum-related neck traumas [2]. The patterns of strain, load and resulting damages on thecervical structures of the impacted porcine specimens were also similar to those clinically observed in injured players,with the caudal vertebrae (C4-C6) more prone to damages (6 out of 8 specimens) as a consequence of the impact.Fractures resulted from tension in the vertebral bodies due to first order buckling of the cervical spine in extension. Themean maximum load in the cranial and caudal load cells was 5.8±2.0 kN and 6.0±2.1 kN and was reached at a time of5.1±1.0 ms and 5.6±1.1 ms after impact, respectively.",
author = "Ezio Preatoni and Dario Cazzola and Timothy Holsgrove and Sabina Gheduzzi and Anthony Miles and Keith Stokes and Harinderjit Gill and Grant Trewartha",
year = "2015",
language = "English",
pages = "10",
booktitle = "Abstract Book of The 25th Congress of the International Society of Biomechanics",

}

TY - GEN

T1 - An integrated multiscale analysis of injury mechanisms in sport impacts: an application to cervical spine biomechanics in rugby union scrummaging

AU - Preatoni, Ezio

AU - Cazzola, Dario

AU - Holsgrove, Timothy

AU - Gheduzzi, Sabina

AU - Miles, Anthony

AU - Stokes, Keith

AU - Gill, Harinderjit

AU - Trewartha, Grant

PY - 2015

Y1 - 2015

N2 - Introduction and Objectives: By generating repetitive high-energy impacts (during the engagement phase) and intensesustained loads (during the sustained push phase) under unstable conditions [1], the Rugby Union scrum has beenindicated as a possible risk factor for degenerative spinal injuries for forward players, and has been associated with~40% of all catastrophic injuries in rugby [2]. However, little is known about how these external loading conditionstranslate into internal stresses on the spinal structures. The aim of this study was to investigate the biomechanics ofcervical spine injury during rugby activities using an integrative approach: in-vivo and in-vitro experiments combined withmusculoskeletal modelling.Methods: Three levels of analysis (Levels 1-3) were integrated. Level 1 was a biomechanical study of scrummaging (N=9experienced rugby forwards) including motion capture (Oqus, Qualisys, Sweden), force measurement (force plates:Kistler 92876BA, Switzerland; and instrumented scrum machine, [1]), and EMG of neck and trunk muscles (DelsysTrigno, Delsys Inc, USA), carried out to assess the external kinematic and kinetic conditions acting on front row players.The subsequent phases of scrummaging, initial engagament (impact and shock absorption) and sustained push, wereobserved. Level 2 developed a bespoke musculoskeletal model (Rugby Model, [3]), consisting of 27 anatomicalsegments, 26 joints, 78 cervical muscles, and 11 torque actuators, in OpenSim (OpenSim 3.2, SimTK, USA). The RugbyModel was driven by the experimental data from Level 1 and was used to estimate joint dynamics, with a specific interestin cervical joint motions and moments. Level 3 performed an in-vitro laboratory experiment to study the injurymechanisms of porcine cervical spines subjected to impact loading conditions similar to those during scrummaging. Load(2 load cells: SLC41/005000, RDP Electronics Ltd, UK) and deformations caused by impacts (mass of 12.86 kg droppedfrom a height of 250 mm to give an impact velocity of ~2.2 m/s) were measured in a custom made impact rig, and highspeedvideos (2 Fastcam SA3, Photron Europe Ltd, UK) were used to investigate the mechanisms of injury throughdigital image correlation (Vic-3D 2009.1.0, Correlated Solutions Inc, USA).Results: Results from the biomechanical analysis confirmed that the load acting on the players, especially during theinitial engagement, was of a considerable magnitude (~2.8 kN compression force in single-player machinescrummaging). Muscle activation patterns were affected by scrummaging conditions (e.g. machine vs. contestedscrummaging; ‘Crouch-touch-set’ vs. ‘Crouch-bind-set’ sequence) and phases of the scrum (e.g. pre-engagement vs.engagement vs. sustaned push). For example, the activity of the erector spinae was significantly lower (in excess of 65%)in machine scrummaging than in contested scrummaging, and the activation of sternocleidomastoid and upper trapeziusthrough pre-engagement and engagement were higher in the current ‘Crouch-bind-set’ technique than in the past ‘Crouchtouch-set’ one. The computational musculoskeletal model highlighted an antiphase change in movement and loadingpatterns between the upper and lower cervical levels (i.e. flexion load on the lower vertebrae and extension on the uppervertebrae), and resulted in a “flattening” of the lordotic cervical curve during the impact phase. The present findings donot provide direct evidence for injury mechanisms but seem in line with the patterns of injury that previous authors havedescribed in relation with scrum-related neck traumas [2]. The patterns of strain, load and resulting damages on thecervical structures of the impacted porcine specimens were also similar to those clinically observed in injured players,with the caudal vertebrae (C4-C6) more prone to damages (6 out of 8 specimens) as a consequence of the impact.Fractures resulted from tension in the vertebral bodies due to first order buckling of the cervical spine in extension. Themean maximum load in the cranial and caudal load cells was 5.8±2.0 kN and 6.0±2.1 kN and was reached at a time of5.1±1.0 ms and 5.6±1.1 ms after impact, respectively.

AB - Introduction and Objectives: By generating repetitive high-energy impacts (during the engagement phase) and intensesustained loads (during the sustained push phase) under unstable conditions [1], the Rugby Union scrum has beenindicated as a possible risk factor for degenerative spinal injuries for forward players, and has been associated with~40% of all catastrophic injuries in rugby [2]. However, little is known about how these external loading conditionstranslate into internal stresses on the spinal structures. The aim of this study was to investigate the biomechanics ofcervical spine injury during rugby activities using an integrative approach: in-vivo and in-vitro experiments combined withmusculoskeletal modelling.Methods: Three levels of analysis (Levels 1-3) were integrated. Level 1 was a biomechanical study of scrummaging (N=9experienced rugby forwards) including motion capture (Oqus, Qualisys, Sweden), force measurement (force plates:Kistler 92876BA, Switzerland; and instrumented scrum machine, [1]), and EMG of neck and trunk muscles (DelsysTrigno, Delsys Inc, USA), carried out to assess the external kinematic and kinetic conditions acting on front row players.The subsequent phases of scrummaging, initial engagament (impact and shock absorption) and sustained push, wereobserved. Level 2 developed a bespoke musculoskeletal model (Rugby Model, [3]), consisting of 27 anatomicalsegments, 26 joints, 78 cervical muscles, and 11 torque actuators, in OpenSim (OpenSim 3.2, SimTK, USA). The RugbyModel was driven by the experimental data from Level 1 and was used to estimate joint dynamics, with a specific interestin cervical joint motions and moments. Level 3 performed an in-vitro laboratory experiment to study the injurymechanisms of porcine cervical spines subjected to impact loading conditions similar to those during scrummaging. Load(2 load cells: SLC41/005000, RDP Electronics Ltd, UK) and deformations caused by impacts (mass of 12.86 kg droppedfrom a height of 250 mm to give an impact velocity of ~2.2 m/s) were measured in a custom made impact rig, and highspeedvideos (2 Fastcam SA3, Photron Europe Ltd, UK) were used to investigate the mechanisms of injury throughdigital image correlation (Vic-3D 2009.1.0, Correlated Solutions Inc, USA).Results: Results from the biomechanical analysis confirmed that the load acting on the players, especially during theinitial engagement, was of a considerable magnitude (~2.8 kN compression force in single-player machinescrummaging). Muscle activation patterns were affected by scrummaging conditions (e.g. machine vs. contestedscrummaging; ‘Crouch-touch-set’ vs. ‘Crouch-bind-set’ sequence) and phases of the scrum (e.g. pre-engagement vs.engagement vs. sustaned push). For example, the activity of the erector spinae was significantly lower (in excess of 65%)in machine scrummaging than in contested scrummaging, and the activation of sternocleidomastoid and upper trapeziusthrough pre-engagement and engagement were higher in the current ‘Crouch-bind-set’ technique than in the past ‘Crouchtouch-set’ one. The computational musculoskeletal model highlighted an antiphase change in movement and loadingpatterns between the upper and lower cervical levels (i.e. flexion load on the lower vertebrae and extension on the uppervertebrae), and resulted in a “flattening” of the lordotic cervical curve during the impact phase. The present findings donot provide direct evidence for injury mechanisms but seem in line with the patterns of injury that previous authors havedescribed in relation with scrum-related neck traumas [2]. The patterns of strain, load and resulting damages on thecervical structures of the impacted porcine specimens were also similar to those clinically observed in injured players,with the caudal vertebrae (C4-C6) more prone to damages (6 out of 8 specimens) as a consequence of the impact.Fractures resulted from tension in the vertebral bodies due to first order buckling of the cervical spine in extension. Themean maximum load in the cranial and caudal load cells was 5.8±2.0 kN and 6.0±2.1 kN and was reached at a time of5.1±1.0 ms and 5.6±1.1 ms after impact, respectively.

UR - http://www.isbglasgow.com/index.php/scientific-information/isb-2015-programme

M3 - Conference contribution

SP - 10

BT - Abstract Book of The 25th Congress of the International Society of Biomechanics

ER -