Knowledge of the distributions of cervical-spine curvature is needed for computational studies of cervical-spine injury in motor-vehicle crashes. Many methods of specifying spinal curvature have been proposed, but they often involve qualitative assessment or a large number of parameters. The objective of this study was to develop a quantitative method of characterizing cervical-spine curvature using a small number of parameters. 180 sagittal X-rays of subjects seated in automotive posture with their necks in neutral, flexed, and extended postures were collected in the early 1970s. Subjects were selected to represent a range of statures and ages for each gender. X-rays were reanalyzed using advanced technology and statistical methods. Coordinates of the posterior margins of the vertebral bodies and dens were digitized. Bézier splines were fit through the coordinates of these points. The interior control points that define the spline curvature were parameterized as a vector angle and length. By defining the length as a function of the angle, cervical-spine curvature was defined with just two parameters: superior and inferior Bézier angles. A classification scheme was derived to sort each curvature by magnitude and type of curvature (lordosis versus S-shaped versus kyphosis; inferior or superior location). Cervical-spine curvature in an automotive seated posture varies with gender and age but not stature. Average values of superior and inferior Bézier angles for cervical spines in flexion, neutral, and extension automotive postures are presented for each gender and age group. Use of Bézier splines fit through posterior margins offers a quantitative method of characterizing cervical-spine curvature using two parameters: superior and inferior Bézier angles.
Issue Section:
Technical Briefs
References
1.
Mertz
, H.
, Jr., and Patrick
, L.
, 1967, “Investigation of the Kinematics and Kinetics of Whiplash
,” Proc. 11th Stapp Car Crash Conference, Paper No. 670919, Society of Automotive Engineers
, Warrendale, PA
.2.
Mertz
, H.
, Jr., and Patrick
, L.
, 1972, “Strength and Response of the Human Neck
,” Proc. 15th Stapp Car Crash Conference, Paper No. 710855, Society of Automotive Engineers
, Warrendale, PA
.3.
Ewing
, C.
, and Thomas
, D.
, 1973, “Torque Versus Angular Displacement Response of Human Head To – Gx Impact Acceleration
,” Proc. 17th Stapp Car Crash Conference, pp. 309
–342
, Society of Automotive Engineers
, Warrendale, PA
.4.
Winkelstein
, B.
, and Myers
, B.
, 1997, “The Biomechanics of Cervical Spine Injury and Implications for Injury Prevention
,” Med. Sci. Sports Exerc.
, 29
(7 Suppl
), pp. S246
–S255
.5.
Nightingale
, R.
, Camacho
, D.
, Armstrong
, A.
, Robinette
, J.
, and Myers
, B.
, 2000, “Inertial Properties and Loading Rates Affect Buckling Modes and Injury Mechanisms in the Cervical Spine
,” J. Biomech.
, 33
(2
), pp. 191
–197
.6.
Luan
, F.
, Yang
, K.
, Deng
, B.
, Begeman
, P.
, Tashman
, S.
, and King
, A.
, 2000, “Qualitative Analysis of Neck Kinematics During Low-Speed Rear-End Impact
,” Clin. Biomech.
, 15
(9
), pp. 649
–657
.7.
Van Ee
, C.
, Nightingale
, R.
, Camacho
, D.
, Chancey
, V.
, Knaub
, K.
, Sun
, E.
, and Myers
, B.
, 2000, “Tensile Properties of the Human Muscular and Ligamentous Cervical Spine
,” Stapp Car Crash J.
, 44
, pp. 85
–102
.8.
Ching
, R.
, Watson
, N.
, Carter
, J.
, and Tencer
, A.
, 1997, “The Effect of Post-Injury Spinal Position on Canal Occlusion in a Cervical Spine Burst Fracture Model
,” Spine
, 22
(15
), pp. 1710
–1715
.9.
McElhaney
, J.
, Doherty
, B.
, Paver
, J.
, Myers
, B.
, and Gray
, L.
, 1988, “Combined Bending and Axial Loading Responses of the Human Cervical Spine
,” Proc. 32nd Stapp Car Crash Conference, Paper No. 881709, pp. 21
–28
, Society of Automotive Engineers
, Warrendale, PA
.10.
McElhaney
, J.
, Paver
, J.
, McCrackin
, H.
, and Maxwell
, G.
, 1983, “Cervical Spine Compression Responses
,” Proc. 27th Stapp Car Crash Conference, pp. 163
–177
, Society of Automotive Engineers
, Warrendale, PA
.11.
Yoganandan
, N.
, Sances
, A.
, Jr., and Pintar
, F.
, 1989, “Biomechanical Evaluation of the Axial Compressive Responses of the Human Cadaveric and Manikin Necks
,” J. Biomech. Eng.
, 11
(3
), pp. 250
–255
.12.
Panjabi
, M.
, and White
, A.
III, 1971, “A Mathematical Approach for Three-Dimensional Analysis of the Mechanics of the Spine
,” J. Biomech.
, 4
(3
), pp. 203
–211
.13.
de Jager
, M.
, Sauren
, A.
, Thunnissen
, J.
, and Wismans
, J.
, 1996, “A Global and a Detailed Mathematical Model for Head-Neck Dynamics
,” Proc. 40th Stapp Car Crash Conference, Paper No. 962430, pp. 269
–281
, Society of Automotive Engineering
, Warrendale, PA
.14.
van der Horst
, M.
, Bovendeerd
, P.
, Happee
, R.
, Wismans
, J.
, and Kingman
, H.
, 2001, “Simulation of Rear End Impact With a Full Body Human Male With a Detailed Neck: Role of Passive Muscle Properties and Initial Seating Posture
,” Proc. 17th International Technical Conference on the Enhanced Safety of Vehicles, National Highway Traffic Safety Administration
, Washington, D.C
.15.
Ono
, K.
, Inami
, S.
, Kaneoka
, K.
, Gotou
, T.
, Kisanuki
, Y.
, Sakuma
, S.
, and Miki
, K.
, 1999, “Relationship Between Localized Spine Deformation and Cervical Vertebral Motions for Low Speed Rear Impacts Using Human Volunteers
,” Proc. of the International IRCOBI Conference on the Biomechanics of Impacts, pp. 149
–164
. IRCOBI
, Bron, France
.16.
Zhang
, Q.
, Tan
, S.
, and Teo
, E.
, 2008, “Finite Element Analysis of Head-Neck Kinematics Under Simulated Rear Impact at Different Accelerations
,” Proc. Inst. Mech. Eng.
, 222
(5
), pp. 781
–790
.17.
Teo
, E.
, Zhang
, Q.
, and Huang
, R.
, 2006, “Finite Element Analysis of Head-Neck Kinematics During Motor-Vehicle Accidents: Analysis in Multiple Planes
,” Med. Eng. Phys.
, 29
(1
), pp. 54
–60
.18.
Brolin
, K.
, and Halldin
, P.
, 2004, “Development of a Finite Element Model of the Upper Cervical Spine and a Parameter Study of Ligament Characteristics
,” Spine
, 29
(4
), pp. 376
–385
.19.
Tropiano
, P.
, Thollon
, L.
, Arnoux
, P.
, Huang
, R.
, Kayvantash
, K.
, Poitout
, D.
, and Brunet
, C.
, 2004, “Using a Finite Element Model to Evaluate Human Injuries Application to the HUMOS Model in Whiplash Situation
,” Spine
, 29
(16
), pp. 1709
–1716
.20.
Frechede
, B.
, Saillant
, G.
, Lavaste
, F.
, and Skalli
, W.
, 2003, “Relationship Between Cervical Spine Curvature and Risk of Injury in the Case of Sagittal Impact: A Finite Element Analysis
,” Proc. of the International IRCOBI Conference on the Biomechanics of Impact, Bron, France
.21.
Yoshida
, H.
, and Tsutsumi
, S.
, 2002, “Finite Element Analysis Using Muscles Elements and Experimental Analysis With a New Flexible Neck Model of Whiplash Injuries in Read-End Collisions
,” SAE 2002-01-0021.22.
Deng
, Y.-C.
, and Fu
, J.
, 2001, “Simulation and Identification of the Neck Muscle Activities During Head and Neck Flexion Whiplash
,” Impact Biomechanics
, pp. 13
–24
, Society of Automotive Engineers
, Warrendale, PA
.23.
Jost
, R.
, and Nurick
, G.
, 2001, “Finite Element Simulation of the Biomechanical Response of the Human Body
,” Proc. of the International IRCOBI Conference on the Biomechanics of Impact, pp. 255
–268
, Bron, France
.24.
Wittek
, A.
, Ono
, K.
, and Kajzer
, J.
, 2000, “Finite Element Model for Simulation of Muscle Effects on Kinematic Responses of Cervical Spine in Low-Speed Rear-End Impacts
,” JARI Res. J.
, 22
(5
), pp. 224
–227
.25.
Stemper
, B.
, Kumaresan
, S.
, Yoganandan
, N.
, and Pintar
, F.
, 2000, “Head-Neck Finite Element Model for Motor Vehicle Inertial Impact: Material Sensitivity Analysis
,” Biomed. Sci. Instrum.
, 36
, pp. 331
–335
.26.
Linder
, A.
, Schmitt
, K.-U.
, Walz
, F.
, and Ono
, K.
, 2000, “Neck Modeling for Rear-End Impact Simulations—A Comparison Between a Multi Body System (MBS) and a Finite Element (FE) Model
,” Proceedings of the International IRCOBI Conference on the Biomechanics of Impacts, pp. 491
–494
, Bron, France
.27.
Yoganandan
, N.
, Pintar
, F.
, Gennarelli
, T.
, Eppinger
, R.
, and Voo
, L.
, 1999, “Geometrical Effects on the Mechanism of Cervical Spine Injury Due to Head Impact
,” Proc. of the International IRCOBI Conference on the Biomechanics of Impacts, pp. 261
–270
, Bron, France
.28.
Pintar
, F.
, Yoganandan
, N.
, Voo
, L.
, Cusick
, J.
, Maiman
, D.
, and Sances
, A.
, Jr., 1995, “Dynamic Characteristics of the Human Cervical Spine
,” Proc. of the 39th Stapp Car Crash Conference, pp. 195
–202
, SAE
, Warrendale, PA
.29.
Black
, K.
, McClure
, P.
, and Polansky
, M.
, 1996, “The Influence of Different Sitting Positions on Cervical and Lumbar Posture
,” Spine
, 21
(1
), pp. 65
–70
.30.
Gay
, R.
, 1993, “The Curve of the Cervical Spine: Variations and Significance
,” J. Manipulative Physiolog. Therapeutics
, 16
(9
), pp. 591
–594
.31.
Hardacker
, J.
, Shuford
, R.
, Capicotto
, P.
, and Pryor
, P.
, 1997, “Radiographic Standing Cervical Segmental Alignment in Adult Volunteers Without Neck Symptoms
,” Spine
, 22
(13
), pp. 1472
–1480
.32.
Helliwell
, P.
, Evans
, P.
, and Wright
, V.
, 1994, “The Straight Cervical Spine: Does It Indicate Muscle Spasm?
,” J. Bone Joint Surg. Br. Vol.
, 76
(1
), pp. 103
–106
.33.
Matsumoto
, M.
, Fujimura
, Y.
, Suzuki
, N.
, Toyama
, Y.
, and Shiga
, H.
, 1998, “Cervical Curvature in Acute Whiplash Injuries: Prospective Comparative Study With Asymptomatic Subjects
,” Injury
, 29
(10
), pp. 775
–778
.34.
Spitzer
, V.
, Ackerman
, M.
, Scherzinger
, A.
, and Whitlock
D.
, 1996, “The Visible Human Male: A Technical Report
,” J. Am. Med. Inform. Assoc.
, 3
(2
), pp. 118
–130
.35.
Visscher
, C.
, de Boer
, W.
, and Naeije
, M.
, 1998, “The Relationship Between Posture and Curvature of the Cervical Spine
,” J. Manipulative Physiolog. Therapeutics
, 21
(6
), pp. 388
–391
.36.
Snyder
, R.
, Chaffin
, D.
, and Foust
, D.
, 1975, “Bioengineering Study of Basic Physical Measurements Related to Susceptibility of Cervical Hyperextension-Hyperflexion Injury
,” UM-HSRI-BI-75-6, University of Michigan Highway Safety Research Institute, Ann Arbor.37.
Foust
, D.
, Chaffin
, D.
, Snyder
, R.
, and Baum
, J.
, 1973, “Cervical Range of Motion and Dynamic Response and Strength of Cervical Muscles
,” Proc. of the 17th Stapp Car Crash Conference, pp. 28
–308
, Society of Automotive Engineers
, New York
.38.
Garg
, M.
, Yaparpalvi
, R.
, and Beitler
, J.
, 2004, “Loss of Cervical Spinal Curvature During Radiotherapy for Head-and-Neck Cancers: The Neck Moves, Too
,” Int. J. Radiat. Oncol. Biol. Phys.
, 58
(1
), pp. 185
–188
.39.
Panjabi
, M.
, Pearson
, A.
, Ito
, S.
, Ivancic
, P.
, and Wang
, J.
, 2004, “Cervical Spine Curvature During Simulated Whiplash
,” Clin. Biomech.
, 19
(1
), pp. 1
–9
.40.
Harrison
, D.
, Harrison
, D.
, Janik
, T.
, Jones
, E.
, Cailliet
, R.
, and Normand
, M.
, 2001, “Comparison of Axial and Flexural Stresses in Lordosis and Three Buckled Configurations of the Cervical Spine
,” Clin. Biomech.
, 16
, pp. 276
–284
.41.
Takeshita
, K.
, Murakami
, M.
, Kobayashi
, A.
, and Nakamura
, C.
, 2001, “Relationship Between Cervical Curvature Index (Ishihara) and Cervical Spine Angle (C2-7)
,” J. Orthop. Sci.
, 6
(3
), pp. 223
–226
.42.
Voutsinas
, S.
, and MacEwan
, G.
, 1986, “Sagittal Profiles of the Spine
,” Clin. Orthop. Relat. Res.
, 210
, pp. 235
–242
.43.
Harrison
, D.
, Harrison
, D.
, Cailliet
, R.
, Troyanovich
, S.
, Janik
, T.
, and Holland
, B.
, 2000, “Cobb Method or Harrison Posterior Tangent Method: Which to Choose for Lateral Cervical Readiographic Analysis
,” Spine
, 25
(16
), pp. 2072
–2078
.Copyright © 2012
by American Society of Mechanical Engineers
You do not currently have access to this content.
