Currently, biomechanics has not been able to effectively predict when a mild traumatic brain injury may occur as a result of head impact. To improve prediction of brain trauma and the development of protective innovations, it is important to create an understanding of the relationship between the biomechanics of the head impact event and the structural damage incurred by the brain as a result of that event. The purpose of this research was to examine the relationship between diffusion tensor imaging measures and biomechanical characteristics of a head impact.
Methods
Diffusion tensor imaging was conducted on concussed subjects to identify regions of white matter structural differences. The injury event was reconstructed using physical and finite element methods to identify the biomechanical parameters of the impact as well as strain to the regions of the brain.
Results
A significant relationship was found between shear strain, rotational acceleration, and impact velocity on increases in radial diffusivity and mean diffusivity in the fornix. Linear acceleration was also found to have a weaker but significant relationship with a decrease in radial diffusivity in the cingulum hippocampus.
Conclusion
These results demonstrate that impacts resulting in high shear strains may affect radial diffusivity and mean diffusivity measures, and that impact mechanics likely have an important role in what regions may present differences in diffusion tensor imaging measures.
BrunsJJrHauserWA. The epidemiology of traumatic brain injury: a review. Epilepsia2003; 44: 2–10.
2.
KhongEOdenwaldNHashimE, et al.Diffusion tensor imaging findings in post-concussion syndrome patients after mild traumatic brain injury: a systematic review. Front Neurol2016; 7: 156–156.
3.
Gennarelli TA. The centripetal theory of concussion (CTC) revisited after 40 years and a proposed new symptomcentric concept of the concussions. International Research Council on the Biomechanics of Impact (IRCOBI). Lyon, France: IRCOBI, 2015.
4.
McCrory P, Meeuwisse W, Aubry M, et al. Consensus statement on Concussion in Sport – the 4th International Conference on Concussion in Sport held in Zurich, November 2012. Phys Ther Sport 2013; 14: e1–e13.
5.
HardyWNFosterCDMasonMJ, et al.Investigation of head injury mechanisms using neutral density technology and high-speed biplanar X-ray. Stapp Car Crash J2001; 45: 337–368.
6.
OmmayaAKGennarelliTA. Cerebral concussion and traumatic unconsciousness. Correlation of experimental and clinical observations of blunt head injuries. Brain1974; 97: 633–654.
7.
HashimECaverzasiEPapinuttoN, et al.Investigating microstructural abnormalities and neurocognition in sub-acute and chronic traumatic brain injury patients with normal-appearing white matter: a preliminary diffusion tensor imaging study. Front Neurol2017; 8: 97–97.
8.
IngleseMMakaniSJohnsonG, et al.Diffuse axonal injury in mild traumatic brain injury: a diffusion tensor imaging study. J Neurosurg2005; 103: 298–303.
9.
PolakPLeddyJJDwyerMG, et al.Diffusion tensor imaging alterations in patients with postconcussion syndrome undergoing exercise treatment: a pilot longitudinal study. J Head Trauma Rehab2015; 30: E32–E42.
10.
HulkowerMBPoliakDBRosenbaumSB, et al.A decade of DTI in traumatic brain injury: 10 years and 100 articles later. AJNR Am J Neuroradiol2013; 34: 2064–2074.
11.
Mac DonaldCLDikranianKBaylyP, et al.Diffusion tensor imaging reliably detects experimental traumatic axonal injury and indicates approximate time of injury. J Neurosci2007; 27: 11869–11876.
12.
MesseACaplainSParadotG, et al.Diffusion tensor imaging and white matter lesions at the subacute stage in mild traumatic brain injury with persistent neurobehavioral impairment. Hum Brain Mapp2011; 32: 999–1011.
13.
ChamardELassondeMHenryL, et al.Neurometabolic and microstructural alterations following a sports-related concussion in female athletes. Brain Inj2013; 27: 1038–1046.
14.
MultaniNGoswamiRKhodadadiM, et al.The association between white-matter tract abnormalities, and neuropsychiatric and cognitive symptoms in retired professional football players with multiple concussions. J Neurol2016; 263: 1332–1341.
15.
TremblaySHenryLCBedettiC, et al.Diffuse white matter tract abnormalities in clinically normal ageing retired athletes with a history of sports-related concussions. Brain2014; 137: 2997–3011.
16.
Lao Y, Law M, Shi J, et al. A T1 and DTI fused 3D corpus callosum analysis in pre- vs. post-season contact sports players. Proceedings of SPIE – the International Society for Optical Engineering 2015; 9287: 1–6.
17.
PostAHoshizakiTBGilchristMD, et al.Traumatic brain injuries: the influence of the direction of impact. Neurosurgery2015; 76: 81–91.
18.
PostAKendallMKoncanD, et al.Characterization of persistent concussive syndrome using injury reconstruction and finite element modelling. J Mech Behav Biomed Mater2015; 41: 325–335.
19.
PadgaonkarAJKriegerKWKingAI. Measurement of angular acceleration of a rigid body using linear accelerometers. J Appl Mech1975; 42: 552–556.
20.
O’RiordainKThomasPMPhillipsJP, et al.Reconstruction of real world head injury accidents resulting from falls using multibody dynamics. Clin Biomech (Bristol, Avon)2003; 18: 590–600.
21.
HorganTJGilchristMD. Influence of FE model variability in predicting brain motion and intracranial pressure changes in head impact simulations. Int J Crashworthiness2004; 9: 401–418.
22.
HorganTJGilchristMD. The creation of three-dimensional finite element models for simulating head impact biomechanics. Int J Crashworthiness2003; 8: 353–366.
23.
Nahum A, Smith R and Ward C. Intracranial pressure dynamics during head impact. In: 21st Stapp Car Crash Conference, New Orleans, 19–21 October 1977.
24.
PostAHoshizakiTBZemekR, et al.Pediatric concussion: biomechanical differences between outcomes of transient and persistent (> 4 weeks) postconcussion symptoms. J Neurosurg Pediatr2017; 19: 641–651.
25.
GurdjianESRobertsVLThomasLM. Tolerance curves of acceleration and intracranial pressure and protective index in experimental head injury. J Trauma1966; 6: 600–604.
26.
HolbournAHS. Mechanics of head injuries. Lancet1943; 242: 438–441.
27.
PostABlaine HoshizakiT. Rotational acceleration, brain tissue strain, and the relationship to concussion. J Biomech Eng2015, pp. 137: 1–8–137: 1–8.
28.
MeaneyDFSmithDH. Biomechanics of concussion. Clin Sports Med2011; 30: 19–31, vii.
29.
KleivenS. Predictors for traumatic brain injuries evaluated through accident reconstructions. Stapp Car Crash J2007; 51: 81–114.
30.
Patton DA, McIntosh AS and Kleiven S. The biomechanical determinants of concussion: Finite element simulations to investigate brain tissue deformations during sporting impacts to the unprotected head. J Appl Biomech 2013: 29: 721–730.
31.
Peerless SJ and Rewcastle NB. Shear injuries of the brain. Can Med Assoc J 1967; 96: 577–582.
32.
KleivenS. Why most traumatic brain injuries are not caused by linear acceleration but skull fractures are. Front Bioeng Biotechnol2013; 1: 15–15.
33.
BainACMeaneyDF. Tissue-level thresholds for axonal damage in an experimental model of central nervous system white matter injury. J Biomech Eng2000; 122: 615–622.
34.
Gennarelli TA, Thibault L and Ommaya AK. Pathophysiological responses to rotational and translational accelerations of the head. SAE. 1972; Paper No 720970.
35.
HoshizakiTBPostAKendallM, et al.The relationship between head impact and brain trauma. J Neurol Neurophysiol2014; 5: 1–8.
36.
PostAKendallMCournoyerJ, et al.Falls resulting in mild traumatic brain injury and focal traumatic brain injury: a biomechanical analysis. Int J Crashworthiness2017; 23: 278–289.
