Cervical Spine Loads and Intervertebral Motions During Whiplash

Ivancic, Paul C.; Panjabi, Manohar M.; Ito, Shigeki

doi:10.1080/15389580600789127

Cited by 34 publications

(28 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Present peak canal narrowing was smaller (1.8 vs. 3.5 mm) and peak foraminal height and area narrowing were larger (3.9 vs. 1.8 mm; 6.5 vs. 4.5 mm 2 ) than the previously reported data, likely due to differences in neck loads. The headneck model, with its T1 vertebra fixed to a mini-sled which accelerated horizontally, experienced large shear and tensile neck loads [11] likely increasing canal narrowing. These loads are contrasted by large compressive neck loads of the present model due to straightening of the kyphotic thoracic curvature and upward torso ramping [9], which likely increased foraminal height and area narrowing.…”

Section: Discussionmentioning

confidence: 99%

“…Another cadaveric study demonstrated that physiologic extension can decrease the cervical foraminal area by as much as 20% [8]. Rear crashes simulated using osteoligamentous neck specimens have demonstrated nonphysiologic intervertebral extension and posterior translation of the lower cervical spine [9][10][11]. These motions may potentially cause transient neural tissue compression leading to injury and chronic radicular symptoms in whiplash patients.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Cervical neural space narrowing during simulated rear crashes with anti-whiplash systems

Ivancic

2012

Eur Spine J

Self Cite

View full text Add to dashboard Cite

Purpose Chronic radicular symptoms have been documented in whiplash patients, potentially caused by cervical neural tissue compression during an automobile rear crash. Our goals were to determine neural space narrowing of the lower cervical spine during simulated rear crashes with whiplash protection system (WHIPS) and active head restraint (AHR) and to compare these data to those obtained with no head restraint (NHR). We extrapolated our results to determine the potential for cord, ganglion, and nerve root compression. Methods Our model, consisting of a human neck specimen within a BioRID II crash dummy, was subjected to simulated rear crashes in a WHIPS seat (n = 6, peak 12.0 g and DV 11.4 kph) or AHR seat and subsequently with NHR (n = 6, peak 11.0 g and DV 10.2 kph with AHR; peak 11.5 g and DV 10.7 kph with NHR). Cervical canal and foraminal narrowing were computed and average peak values statistically compared (P \ 0.05) between WHIPS, AHR, and NHR. Results Average peak canal and foramen narrowing could not be statistically differentiated between WHIPS, AHR, or NHR. Peak narrowing with WHIPS or AHR was 2.7 mm for canal diameter and 1.6 mm, 2.7 mm, and 5.9 mm 2 for foraminal width, height and area, respectively. Conclusions While lower cervical spine cord compression during a rear crash is unlikely in those with normal canal diameters, our results demonstrated foraminal kinematics sufficient to compress spinal ganglia and nerve roots. Future anti-whiplash systems designed to reduce cervical neural space narrowing may lead to reduced radicular symptoms in whiplash patients.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Cervical neural space narrowing during simulated rear crashes with anti-whiplash systems

Ivancic

2012

Eur Spine J

Self Cite

View full text Add to dashboard Cite

show abstract

“…The same relations involving points B i and B i−1 can be specified simply by replacing A with B in formulae (45) and (46). As can be seen, the equations of motion (43) can be rearranged and presented in the matrix form (1), where (47) and the matrix M consists of the coefficients a i j .…”

Section: Multibody Model Of Cervical Spinementioning

confidence: 99%

“…6, shape representation of every body is based on eight characteristic points. Similar to the models described in [46,47], the center of mass is positioned at the center of the segment connecting the corners P 1 and P 6 of the vertebral body. It is assumed that point P 5 of the ith member and P 2 of the next one are coupled by a link rigidly connected with the lower body, and the pivot O i+1 is located in the point P 2 .…”

Section: Numerical Experimentsmentioning

confidence: 99%

See 1 more Smart Citation

Application of the MEBDFV solver to dynamic simulation of some specific multibody systems: an example of a cervical spine model

Fritzkowski

Walczak

2014

Int. J. Dynam. Control

View full text Add to dashboard Cite

Application of the MEBDFV code in multibody dynamics is discussed. The solver is based on the modified extended backward differentiation formulae of Cash. It is especially suited for the solution of differential-algebraic equations with time-and state-dependent mass matrix. Such a case can occur when motion of a multibody open-chain system is described within the classical Lagrangian formalism, which still has some advantages. An outline of the numerical algorithm is given. As an example, a simplified mathematical model of the human head-cervical spine system is presented. In a numerical experiment the model is used to analyze motion of the head-neck during rear-end impact which may lead to whiplash injury. The obtained results are compared to literature data. Performance of the MEBDFV solver is examined in terms of algorithmic energy conservation. The test is based on an appropriately formulated 'kinetic energy-work' relation.

show abstract

Whiplash injuries and associated disorders: new insights into an old problem

Rydevik¹,

Szpalski²,

Aebi³

et al. 2008

Eur Spine J

View full text Add to dashboard Cite

SummaryThe Medical Task Force of the Swedish Society of Medicine and the Whiplash Commission has come to the following main conclusions:The term ''whiplash'' is so generally accepted that it should continue to be used, but the term ''whiplash trauma'' should only be used to refer to indirect cervical spine trauma. By deleting WAD grades 0 and IV from the classification system introduced in 1995 by the Quebec Task Force (QTF), the diagnosis of whiplash injury will be more exact and more realistically defined, which will reduce the risk of misunderstanding.The reported incidence of whiplash injuries in Sweden varies depending on the particular investigation cited, and ranges between 1.0 and 3.2/1000 per year. Whiplash injuries represent approximately 1/3 of all claims submitted after traffic injuries to insurance companies in Sweden, and give rise to a medical disability rate of 10% or more. Various studies of how the possibility of an insurance claim influences the course of a whiplash injury have produced quite different results, but generally there is no evidence of significant differences in outcome between those who have and have not sought claim.Ligament injuries can rarely be demonstrated acutely after whiplash trauma, and radiologically verified instability later in the course of the injury is also rare. Experimental studies have shown that whiplash trauma can lead to loads on discs and facet joints that might result in injury of these structures, but there is no scientific evidence to verify such injuries in patients with whiplash injury. Certain studies indicate that a dysfunction in the nervous system may exist in a small proportion of patients with whiplash injury.A series of physiological changes occurs in both the peripheral and the central nervous systems after whiplash injury, comprising peripheral as well as central sensitisation. There is no scientific evidence that such physiological changes are specific to the pain associated with whiplash injury; similar changes have been shown to occur in association with various other pain conditions, acute as well as long-term.It is likely that any previous mental ill-health and the patient's current mental state are both important for the clinical development and course of whiplash injury. To minimise the risk of long-term problems among people with acute whiplash injury, concurrently occurring acute stress disorder (ASD) and/or post-traumatic stress disorder (PTSD) should be diagnosed and treated. It is also important to diagnose and adequately treat possible sleep disorder, depression, or anxiety among people with whiplash injury.Neck problems in terms of pain and stiffness, either with or without objective clinical findings such as decreased range of motion and tenderness at palpation (WAD grades I and II), are most common. Symptoms usually appear within the first day and up to a few days after whiplash trauma. Headache commonly occurs, along with pain in the shoulders and the thoracic spine. Neurological symptoms are present in approximately 20% of pat...

show abstract

Cervical Spine Loads and Intervertebral Motions During Whiplash

Abstract: During whiplash, the cervical spine is subjected to not only bending moments, but also axial and shear forces. These combined loads caused both intervertebral rotations and translations.

Cited by 34 publications

References 35 publications

Cervical neural space narrowing during simulated rear crashes with anti-whiplash systems

Cervical neural space narrowing during simulated rear crashes with anti-whiplash systems

Application of the MEBDFV solver to dynamic simulation of some specific multibody systems: an example of a cervical spine model

Whiplash injuries and associated disorders: new insights into an old problem

Contact Info

Product

Resources

About