Monthly Archives: June 2012

Does Chronic Neck Pain Lead to Other Pain?

In a recent study (1), patients with chronic neck pain experienced more somatosensory pain than patients with acute neck pain. The somatosensory system in the human body refers to sensations felt by sensory organs other than the eyes or ears. It is how we feel whether something is hot or cold, rough or smooth. It is how we sense our outside world whether we can see or hear.

As a child, you probably learned this 5th sense as “touch,” but the system is far more complicated. There are several different types of receptors that lie in the surface of the skin,
organs or muscle tissue. When stimulated by a physical cause (heat, pressure, injury etc.), the message is taken by the connecting sensory nerves, to the spinal cord and to a specific area in the brain that holds a sort of “map” of your body. The final sensation (pain, burn, sting etc.) is then “felt.”

Can you see why a person with chronic neck pain may “feel” more somatosensory pain? Though the system is vast and quite complicated, chronic problems with spinal alignment (as seen in patients with chronic neck pain) may cause communication problems between the outer branches of nerves, spinal cord and brain.

In fact, we often forget that the spine serves as the protector of the spinal cord, and that the spinal cord and the branching nerves are in charge of virtually every communication between the body and the brain. Back pain and neck pain can be indicators of spinal degeneration, inflammation and potentially, compression of nerves whose communication may be compromised.

(1) Journal of Manipulative and Physiological Therapeutics Khodabakhsh Javanshir,
Ricardo Ortega-Santiago, Mohammad Ali Mohseni-Bandpei, Juan C. Miangolarra-Page,
César Fernández-de-las-Peñas Exploration of Somatosensory Impairments in Subjects With
Mechanical Idiopathic Neck Pain: A Preliminary Study Volume 33, Issue 7, Pages 483-556
(September 2010) pages 493-499

Low-Impact Crashes Can Lead to Long-Term Jaw Pain

Low-impact crashes can lead to jaw painAdults who suffer whiplash trauma in motor vehicle collisions often experience a range of head and neck symptoms that linger long after the collision. However, the connection between whiplash and jaw symptoms, including temporomandibular joint disorder (TMD), is a subject of ongoing research and some controversy. Although some studies have shown that whiplash can increase the risk of jaw disorders by 3.4%, other researchers have discounted this finding.1

One difficulty in understanding this relationship arises because people involved in a collision may not report jaw pain or masticatory problems until some time after the original incident. This may be because patients do not recognize jaw pain as a serious issue in the acute aftermath of a crash or because the symptoms do not manifest until some weeks after the incident. Either way, the delay makes it difficult to directly attribute jaw symptoms to a collision. Additionally, research into psychological factors like post-traumatic stress has shown that a patient’s mental health can impact physical symptoms over time.

Researchers based at the Universityof Gothenburgin Sweden2 set out to help define the prevalence of jaw problems in whiplash patients by tracking symptoms in 128 patients over the course of a year after their initial trauma. They also sought to find out whether jaw symptoms may be connected to a particular location of neck injury. This study is part of a longitudinal study of collision survivors in the Gothenburg region, aged 18 years and older, who were diagnosed with whiplash-associated neck problems and who had entered the study within 5 weeks of the accident.

The participants completed an initial assessment that analyzed a long list of crash conditions, including impact direction, subject’s posture at the time of the crash, trajectory, and the participant’s reactions during the crash. They also underwent an initial physical examination that assessed their cervical range of motion, the presence or absence of jaw signs (asymmetrical jaw opening, reduced mouth opening, and associated pain), as well as a psychological examination for post-traumatic stress. A number of participants who were in crashes involving Volvos had additional information provided by the company’s crash investigation team. The participants then completed a follow-up questionnaire and physical examination after one year.

During the initial examinations, jaw signs were noted in 36% of men and 37% of women. After a year, examiners found jaw signs in 23% of men and 24% of women. For around 10% of the women, these signs had developed over the course of the year. Women with jaw signs during the first exam were more likely to also report experiencing headaches (93%) than those without (75%), but this divergence was not significant among the men. Over half of patients with cranial symptoms reported headache after one year, while only one of those with caudal symptoms did so. Patients with cranial neck symptoms were significantly more likely to manifest jaw signs than those with caudal symptoms.

Symptoms and jaw signs were more common after a year in patients involved in rear-end collisions, and were significantly more common in patients still experiencing neck pain. According to the researchers, “The odds for having jaw signs after one year in subjects with residual neck problems of any grade was 4.8 times that of participants without residual neck problems.”

One of the most interesting findings was that there was no correlation between the severity of the initial crash or impact speed and the prevalence of jaw symptoms. This conclusion contradicts the assumption that the change in speed at the time of the crash can predict the severity of injuries. Participants involved in slower crashes were just as likely to experience longer-term jaw problems, although the direction of the impact (rear, front, or side) and the sex of the vehicle occupant did seem to be significant factors.

These results suggest that the long-term risk of jaw problems following a collision many be sex-specific, with women at greater risk of developing symptoms. Such findings are in line with other research3 that suggests women are at a physiological disadvantage in crash situations. The researchers conclude that jaw problems may be easily overlooked in the acute phase of a crash and discounted over the long term. Health professionals should evaluate patients over the long term to catch the full range of symptoms that may crop up after a motor vehicle collision.

  1. Carroll LJ, Ferrari R, Cassidy JD. Reduced or painful jaw movement after collision-related injuries: a population-based study. Journal of the American Dental Association. 2007; 138:86-93.
  2. Severinsson Y, Bunketorp O, Wenneberg B. Jaw Symptoms and signs and the connection to cranial cervical symptoms and post-traumatic stress during the first year after a whiplash trauma. Disability and Rehabilitation. 2010. 32(24).
  3. Vasavada AN, Danaraj J, Siegmund GP. Head and neck anthropometry, vertebral geometry and neck strength in height-matched men and women. Journal of Biomechanics 2007.

Spinal Manipulation and Whiplash

Whiplash accounts for at least 30% of injuries reported following a traffic accident. Fortunately, whiplash is not usually a serious injury and certainly, one should be grateful for the ability to walk away from an accident.

However, the mere fact that it is not regarded as a serious injury by many people who shrug off the post-accident aches and pains may lead to lack of treatment. A few days of over-the-counter pain medications may be the only treatment many seek.

Unfortunately, the longer whiplash is left untreated, the more damage could occur. Whiplash occurs as a result of the neck being thrust forward past its intended range of motion. When this happens, inflammation causes pain and over time, left untreated, degenerative changes in the cervical spinal region. All of this can lead to further degeneration, partial immobility, shoulder pain and cervicogenic headaches.

Many people who have neck problems later in life could attribute their neck problems to a past injury of the neck that was not treated properly.

Fortunately, the treatment for whiplash is noninvasive and quite successful. Chiropractic care for whiplash is often covered under insurance policies, if treatment is sought soon after the accident.

In a recent study, it was shown that spinal manipulation of the spine may benefit patients with whiplash. A 37-year-old woman was followed for 12 months to see if manual therapy would reduce her pain following a whiplash injury that included pain in the neck and shoulder area.

The patient was treated over six weeks with 11 visits. Treatment consisted of manipulation and specific exercises. The authors found:

“Her pain decreased from 9/10 to 2/10 by the end of treatment and remained improved at 1/10 at the 6-month follow-up. Her Copenhagen Neck Functional Disability Scale decreased from 23/30 to 4/30 by the 11th visit. In addition, she demonstrated clinically significant increases in cervical active range of motion and normal somatosensation.”

Lowry CD, O’Hearn MA, Courtney CA. Resolution of whiplash-associated allodynia following cervicothoracic thrust and non-thrust manipulation. Physiotherapy Theory and Practice 2010;October 5.

10 Year Follow-Up of Whiplash Patients

Whiplash injuries are a common consequence of rear-end collisions, and insurance claims related to neck pain from collisions may cost over $8 billion per year, according to the Insurance Institute for Highway Safety. Whiplash-associated disorders (WAD) can encompass a wide range of symptoms, including neck pain, shoulder stiffness, headaches, and back pain. However, little is yet understood about the long-term impacts of whiplash.

One outstanding question has been whether whiplash injuries accelerate the natural degeneration of the spine. Researchers inJapanrecently published the first long-term follow up of whiplash-associated disorder (WAD) patients that compared their MRI results with a control group. They found that while whiplash-related pain symptoms could linger for over a decade, this did not seem to correlate to increasing rates of spinal degeneration.

Between 2005 and 2007, 133 WAD patients and 223 people with no history of symptoms were recruited from among those who had participated in an acute whiplash study 10 years prior. Participants from both groups completed a physical examination and were questioned about any neck or spine-related issues. WAD patients also reported whether their whiplash symptoms had improved since the initial study. All patients were given an MRI examination of the cervical spine. Two neurologists, who were unaware of the patient group assignments, evaluated the images for decreases in signal intensities, disc protusions, and foraminal stenosis.

A significant number of the patients reported continuing symptoms, even ten years after the crash:


After Crash




Neck Pain





Stiff Shoulder










Arm Pain





While the majority of WAD patients reported that their symptoms had improved over 10-years after the initial injury, when compared to the control group, they still suffered from increased rates of

neck pain, shoulder stiffness, headaches, and arm numbness. The researchers suggest that, “WAD patients may have long-lasting clinical symptoms for as long as 10 years after their initial injuries in

addition to the natural aging process.” Over a quarter of WAD patients reported neck pain, compared to just 10% of control subjects, and they were nearly four times more likely to experience headaches.

When the MRIs were examined, a progressive decrease in signal intensity was noted in both WAD patients and the control group, but the rate was much higher for WAD patients (82% versus 59%). Other progressive degenerative indicators were observed in both groups, but there was no significant difference in the rates of degeneration between the two groups. Women from both patient groups exhibited more cervical-spine conditions over the long-term than men, but female WAD patients were no more likely to exhibit deterioration than control subjects.

These findings bolster the case that accidents involving whiplash can have a long-term impact on patient health and comfort, even though, as the study authors conclude, “whiplash injury may not accelerate the structural deterioration of the cervical spine during 10 years after the injury.”

Matsumoto M, Okada E, Ichihara D, Chiba K, Toyama Y, Fujiwara H, Momoshima S, Nishiwaki Y, Hashimoto T, Inoue T, Watanabe M, Takahata T. Prospective ten-year follow-up study comparing patients with whiplash-associated disorders and asymptomatic subjects using magnetic resonance imaging. Spine. 2010. 34:18. pp. 1684-1690.

Whiplash Causes Brain Injury in 23% of Cases

Whiplash causes brain injuryPeople who experience whiplash during a motor vehicle accident can suffer from a variety of short- and long-term symptoms, including neck and back pain, headaches, and injury to the spine. While some in the medical profession have suggested that whiplash may also cause injuries to the brain, few studies have looked directly at this connection. Without scientific evidence that whiplash can lead to brain injury, it is difficult to attribute changes in the brain to trauma incurred during a collision.

A study published in the July 2010 issue of Brain Injury investigates the connection between whiplash and Chiari Type I malformation, a condition in which the cerebellar tonsils at the base of the brain become herniated, pushing through an opening in the bottom of the skull. This condition—also called cerebellar tonsillar ectopia (CTE)—can cause headaches, numbness, weakness, and brain disorders. The findings of this study indicate that whiplash may indeed cause this type of brain injury in more than a fifth of cases. The study also suggests that traditional MRIs, administered with the patient laying down, are less effective at revealing this damage than MRIs conducted on patients who are upright.

A team of researchers led by Michael Freeman of the Oregon Health and Science University School of Medicine and Ezriel Kornel of Columbia University’s Department of Neurological Surgery compared cervical MRI scans from a total of 1200 patients with neck pain. Half of the study participants attributed their neck pain to a motor vehicle accident, while the other half did not have a recent history of trauma. For each group of patients, half of the MRIs were administered with study participants in an upright position, and the remaining were performed with patients in a recumbent position.

After comparing the MRI scans, the researchers found that patients with a history of trauma from a motor vehicle accident had a much higher rate of CTE than patients with neck pain that was not associated with trauma. In the non-trauma group, 5-6% of patients had scans that revealed CTE. In the trauma group, 9% of patients scanned in a recumbent position showed CTE, while 23% of patients scanned in an upright position showed CTE. Female patients across all groups showed the highest rates of CTE.

The study is the first to show substantial differences in the brain anatomies of patients who have experienced whiplash compared to those who have not. It also provides compelling evidence that traditional, recumbent MRI imaging may be insufficient to reveal brain injury after an accident—

upright MRI scans were shown to be 2.5 times more sensitive to detecting CTE in patients with a history of trauma. The study authors suggest that the CTE detected in the trauma group of patients may be caused when an accident causes damage to the dural covering of the brain and spine, in effect creating a leak of cerebrospinal fluid. The lower level of fluid means the brain itself would sit lower in the skull when a person is standing or sitting up—one explanation for why the CTE might only be visible in upright MRI scans.

Symptoms of CTE can include suboccipital headaches, ocular symptoms, muscular weakness, and impaired sensation.

These findings have immense practical application for both clinicians looking into the effects of auto injuries, and to attorneys representing clients who may have incurred brain damage and other injuries from a collision.

Freeman MD, Rosa S, Harshfield D, Smith F, Bennett R, Centeno CJ, Kornel E, Nystrom A, Heffez D, Kohles SS. A case-control study of cerebellar tonsillar ectopia (Chiari) and head/neck trauma (whiplash). Brain Injury, July 2010; 24(7–8): 988–994.

Jaw Pain After Whiplash: The Cervical Connection

Jaw pain after whiplashPeople who experience whiplash during a collision can suffer from a range of associated health symptoms, including headaches and neck injury. Jaw pain caused by a dislocation of the temporomandibular joint (TMJ) is less frequently reported immediately following a whiplash trauma, but these symptoms can develop later. When jaw symptoms are not included in the initial injury report, however, it can be difficult to show whether they are related to an accident. A new study attempts to clarify the link between whiplash and jaw symptoms, both immediately after a trauma and over time.

Researchers from the University of Gothenburg in Sweden followed 146 patients who had suffered a whiplash trauma for a year after their accidents. All participants had entered the study within 5 weeks of being involved in a crash, and the research excluded those who had a previous history of neck injury or whose injuries were serious enough to require hospitalization.

Around 4% of the participants reported having difficulty opening their mouths or chewing during the initial 5 weeks after the crash. A year later, these same jaw symptoms were felt by 10% of the participants, all of them women. The researchers also had the study participants examined initially and one year post-trauma to determine their range of cervical motion, whether their jaw movement was asymmetrical, and whether their ability to open their mouths was reduced. Around 36% of those examined showed some initial signs of reduced or asymmetrical movement. An additional 4% of men and 9% of women displayed these jaw signs during the subsequent examination one year later.

No correlation was found between the severity of the crash and instances of jaw pain—which means those involved in low-impact crashes were just as likely to suffer symptoms as those in more severe accidents. Participants who suffered from cranial cervical headaches were at greater risk of experiencing jaw disorders.

The researchers conclude that although jaw symptoms are rarely reported immediately following a whiplash trauma, they can develop over time, particularly after low-speed, rear-end collisions. The risk seems to be greater for women than for men, and is highest among those who report headache and/or cranial neck problems.

TMJ and the Cervical Spine

This study is important for a number of reasons. It shows that TMJ symptoms are not uncommon after whiplash, and that the symptoms are often delayed.

It also reinforces the concept that jaw pain after an auto collision is most likely rooted in the cervical spine—not the jaw itself.

This concept is not new. Stiesch-Scholz et al in 2003 found that cervical spine injury was related to TMJ dysfunction. Klobas et al 3 found the same thing in 2004, stating:

“We conclude that the prevalence of symptoms and signs of TMD is much higher in patients with chronic WAD compared with an age- and sex-stratified group of recall patients. Trauma to the neck region may affect the temporomandibular functional complex causing pain and dysfunction.”

These studies show that there is a distinct relationship between TMJ pain and whiplash. Focusing treatment on the cervical spine seems like the logical place to treat jaw symptoms after an auto injury when direct trauma is absent

  1. Severinsson Y, Bunketorp O, Wenneberg B. Jaw symptoms and signs and the connection to cranial cervical symptoms and post-traumatic stress during the rst year after a whiplash trauma. Disability and Rehabilitation, 2010, May 8.
  2. Stiesch-Scholz M, Fink M, Tschernitschek H. Comorbidity of internal derangement of the temporomandibular joint and silent dysfunction of the cervical spine. Journal of Oral Rehabilitation 2003;30:386-391.
  3. Klobas L, Tegelberg A, Axelsson S. Symptoms and signs of temporomandibular disorders in individuals with chronic whiplash-associated disorders. Swedish Dental Journal 2004;28:29-36.

Whiplash Symptoms: Much More Than Just Neck Pain

Whiplash symptoms

Over the years, many different pain symptoms have been reported by auto injury patients. While most symptoms of whiplash are focused around the obvious injury point of the neck, there are many reports of pain in other parts of the body. Unfortunately, many research studies focus exclusively on the neck and ignore the rest of the body.

A group of Canadian researchers decided to look at a whole-body perspective of whiplash. The authors had 6,481 auto injury patients complete a body pain diagram, marking where they felt pain as a result of the collision.

The study reported the following areas of pain:

Symptom                                Percentage of Patients Reporting

Posterior neck pain                          86.2

Posterior shoulder pain                 75.3

Head pain                                             72.0

Mid back pain                                     65.5

Lumbar pain                                        60.4

Buttock pain                                         42.2

Anterior neck pain                             38.0

Anterior shoulder pain                     35.9

Upper extremity pain                        35.1

Lower extremity pain                        27.5

Chest pain                                                18.9

Abdomen pain                                      15.9

Groin pain                                             1.8


This data only tells part of the story, however, because very few patients had isolated symptoms in just one part of the body. Many reported much more widespread pain:


Symptom                                                                                            Percentage of Patients Reporting

Posterior neck and shoulder pain                                                                    72.7

Posterior neck, shoulder, and head pain                                                        57.7

Posterior neck, shoulder, mid-back, and head pain                                  46.3

Posterior neck, shoulder, mid-back, low back, and head pain             33.3

Any posterior trunk pain                                                                                     95.1

Entire posterior trunk pain                                                                                  26.5

As we can see from this chart, many patients had wide-ranging torso pain after their crash. In fact, 26% of the patients had entire posterior trunk pain!

“Our results suggest that conceptualizing pain after traffic injury as primarily neck pain may be misdirected. The majority of adults with traffic injuries report bodily pain over multiple body areas and mainly within the posterior trunk region, made up of the posterior neck, posterior shoulder, mid-back, lumbar, and buttock areas. Pain confined to a single body area was extremely rare. Although neck pain after traffic injury is common, it rarely occurs by itself.”

The authors conclude that their study has important consequences for both researchers and clinicians:

“Our study better informs randomized controlled trials on whiplash injury that focus on the treatment and improvement of neck pain alone and suggests that these might be missing an important and potentially relevant part of the clinical presentation after traffic injury. The current findings also suggest that the search for pathophysiological pain mechanisms after traffic injury must fully account for all bodily pain arising after a MVC. In the past, this search has focused too often on neck pain alone and the whiplash mechanism from rear-end collision. Future studies should not use leading questions about implicitly defined pain locations, but rather offer study participants the opportunity to report the total area of pain on a pain drawing. Similarly, the use of pain drawings in clinical settings would provide clinicians with a more complete profile of all symptomatic areas and allow potentially important patterns of pain to be considered and treated if necessary.”

Hincapie CA, Cassidy JD, Cote P, et al. Whiplash Injury is More Than Neck Pain: A Population-Based Study of Pain Localization After Traffic Injury. Journal of Occupational and Environmental Medicine 2010;52(4):434-440.

Facet Joints May Be Source of Chronic Hypersensitivity After Whiplash

Whiplash pain and facet jointsWhiplash patients frequently suffer from increased sensitivity to a variety of stimuli across the entire body, even in areas far from the injury site. This sensory hypersensitivity causes various secondary health problems, and its presence indicates a poor prognosis for resolution of whiplash symptoms. The origins of sensory hypersensitivity have been unclear, making it difficult for doctors to create effective treatment plans. Fortunately, a study1 published last month by a Canadian research team offers new insight into the source of this common condition in whiplash patients.

Researchers from the University of Calgary conducted an exploratory study to determine whether the cervical zygapophyseal joints, also known as facet joints, might be a primary pain source for sensory hypersensitivity in patients with chronic whiplash associated disorders (WAD). Facet joints connect the vertebrae at the auricular processes, with two facet joints at the top and two at the bottom of each vertebra. The facet joints have long been implicated in whiplash pain. In fact, previous studies using nerve block procedures have shown that 54% to 60% of patients with WAD have pain originating from facet joints in the cervical spine.

The study sought to determine whether an anesthetic block of the cervical facet joints would have an effect on generalized sensory hypersensitivity. “We hypothesized that a decrease in cervical spine pain intensity following diagnostic blockade of the zygapophyseal joints would result in a change in measures indicative of sensory hypersensitivity, specifically, an increase in pressure pain thresholds (PPTs) and a decrease in cold pain thresholds (CPTs),” the research team wrote.1

The study included 18 patients with grade II whiplash associated disorders and 18 healthy volunteers, matched for age and gender with the whiplash group. Whiplash patients were included if they reported cervical neck pain for at least 6 months and experienced an 80% decrease in that pain following an intra-auricular facet joint block procedure. Potential whiplash participants were excluded if they exhibited any history of neck pain prior to the whiplash incident, were pregnant, had neurological dysfunction, peripheral vascular disease or coronary artery disease. Potential control group participants were excluded for any spinal, elbow, knee pain or headache, history of motor vehicle accident, or treatment for neck pain or headache in the previous two years.
The experience of pain is initiated by the work of nocioceptors, sensory receptors throughout the body that send pain signals to the brain. The initiation of nocioception, “the neural processes of encoding and processing noxious stimuli,” requires a threshold; that is, a mechanical, chemical or thermal stimulus must exceed a particular threshold to trigger nocioceptors to deliver the pain response.2
Researchers tested cold pain thresholds (CPTs) and pressure pain threshold (PPTs) on study participants at three sites bilaterally. To identify CPTs, thermodes were placed on the skin at each of the testing sites, and the temperature decreased from 32 degrees Celsius to one degree Celsius at a rate of one degree per second. Subjects pushed a self-controlled switch when the sensation turned into one of pain. PPT was measured at three other sites through a similar process. A probe of one centimeter applied pressure at a rate of 40kPa/second, and participants pushed a switch when the pressure became painful.

CPTs and PPTs were measured in whiplash patients both before an after anesthetic block of the cervical facet joints. The results of the tests were compared, using the control subjects responses to establish normative baseline thresholds.

The results were significant, drawing a clear connection between the facet joint and the presence of sensory hypersensitivity. In all test sites, the PPT in whiplash patients was lower than that of the control subjects while the CPT of the whiplash patients was higher, consistent with the presentation of sensory hypersensitivity. After the joint blockade, however, PPT measures in whiplash patients significantly increased, while CPT’s showed a corresponding decrease. The pain thresholds of the whiplash patients did not normalize following the block, which researchers attribute to the complexity of neurological factors involved in nocioception. The fact that a significant amelioration of sensory hypersensitivity occurred following facet joint blockade strongly suggests that the facet joints may serve as a primary source of pain.

The University of Calgary team’s findings invite further research into long-term therapies for whiplash patients suffering from sensory hypersensitivity. Spinal manipulation of the cervical vertebra may be one therapy studied for its ability to interrupt widespread pain signals originating in the facet joints. This study offers hopeful news for patients and doctors trying to reduce the long-term consequences of whiplash.

  1. Schneider et al. Minimizing the source of nociception and its concurrent effect on sensory hypersensitivity: An exploratory study in chronic whiplash patients. BMC Musculoskeletal Disorders 2010;11:29.
  2. Loeser JD, Treede RD. The Kyoto protocol of IASP Basic Pain Terminology. Pain 2008;137(3):473–7.

Motion MRI May Show Ligament Damage in Whiplash Patients

Ligament Damage in Whiplash PatientsProper treatment for victims of an automobile collision depends on a detailed understanding of the extent of the injury. Unfortunately, conventional MRIs are of limited use as an assessment tool for whiplash injury, often failing to show ligament damage in the cervical spine.

“Static imaging does not reveal movement abnormalities,” wrote a group of Finnish researchers in its November 2009 study of whiplash patients. The study introduced motion MRI as an effective tool for highlighting abnormal movement patterns that indicate ligament damage. Whiplash injuries which do not appear on static MRI’s may be now be measurable by using dynamic imaging of the injury site.

Researchers investigated the differences in movement patterns of the upper cervical spine in whiplash trauma patients and a control group. The study included ten male and 15 female whiplash patients who had been admitted to the ORTON Rehabilitation Centre in Helsinki, Finland because of their severe chronic symptoms. Patients suffered from some combination of severe neck pain, headache, upper and lower limb dysfunction, loss of balance, and numbness of the tongue. Patients participated in the study an average of seven years after the original injury, and were still experiencing symptoms.

The control group consisted of ten male and 15 female volunteers, matched for age and sex with the experimental group. None of the control subjects had any history of neck pain, trauma, or inflammatory diseases such as rheumatoid arthritis.

Researchers focused the motion MRI’s on a specific area at the top of the spine. The symptoms exhibited by the whiplash patients indicated a problem in the C0-C2 region of the cervical spine. The C1 and C2, also known as the Atlas and the Axis, are the uppermost vertebrae in the cervical spine. Researchers used dynamic kine magnetic resonance imaging (dMRI) to analyze movement between C1 and C2 during side bending and to assess instability of the C0 and C1 joints. They also measured the signal from the alar ligaments, which connect the C2 vertebra with the occipital bone and control side-to-side movement of the head.

Targeted positioning of the subjects’ necks in the motion MRI allowed for more detailed assessment than a static MRI would offer. “The benefits of side bending the cervical spine is illustrated in patients with normal movement because the opposite alar ligament can be seen as it straightens, and possible changes in the signal can be seen more effectively,” explained the study’s authors.

The results showed significant differences between the whiplash patients and control group. Analysis of the results found abnormal movement in the alar ligaments in 92% of patients compared with 24% of control subjects. Images taken while side bending revealed widening of the C0-C1 joint, an indication of an unstable

joint, in seven patients and one control subject. Furthermore, abnormal movements in the C1-C2 were found in 56% of whiplash patients, compared with 20% of the control group.

Overall the whiplash patients with longstanding symptoms had more abnormal signals from the alar ligaments and greater movement disturbances in the C0-C2 level in the dMRI than the control group.

This study has important implications for the assessment of whiplash injury. “Conventional computed tomography and conventional MRI are not appropriate tests with which to rule out pathology,” the researchers warned. Whiplash injuries producing significant symptoms may not be visible through conventional imaging. Fortunately for doctors and victims of auto accidents, motion MRI’s may be able to demonstrate the nature of whiplash injuries where earlier imaging has failed.

Lindgren K-A, Kettunen JA, Paatelma M, Mikkonen RHM. Dynamic kine magnetic resonance imaging in whiplash patients and in age- and sex-matched controls. Pain Research & Management 2009;14(6):427-432.

Dizziness and Balance Problems After Whiplash

Dizziness and balance problems after whiplashThe neck plays an important role in not only the support and movement of the head, but also plays a critical role in maintaining balance and posture. Previous studies have demonstrated that severe neck pain can compromise the ability of the neck to stabilize head movements and can contribute to balance problems. What has been uncertain from prior research is whether whiplash trauma in particular may have an effect on head steadiness distinct from the effects of non-traumatic neck pain.

A recent study sought to investigate whether differences exist in head steadiness between patients with whiplash and those with chronic non-traumatic neck pain. Researchers assessed head steadiness in 173 participants, who each represented one of three groups:

  • 59 patients with whiplash-associated disorders (WAD) grades I-II, persisting longer than six months and less than 10 years;
  • 57 patients with chronic non-traumatic neck pain, persisting longer than 6 months and less than 10 years; and
  • 57 healthy volunteers to serve as a controls.

Exclusion criteria for the whiplash group consisted of a diagnosis of WAD grades III-IV, a history of similar symptoms prior to the accident, head injury during the accident, surgery of the cervical spine, or any symptom-related systemic disease. Subjects were excluded from the chronic neck pain group if they had any history of neck trauma or known systemic disease related to the symptoms. The control group had no previous or current history of neck pain or neck trauma, and excluded pregnant women and people unable to participate in an MRI.

Testing required participants to lay in two positions for each of the measured tasks. In the low load task, participants leaned backwards at a 60 degree angle, with full head support to allow a neutral resting position. Subjects were asked to lift their heads one centimeter from the headrest and hold completely still for 40 seconds, as a researcher timed the task. A 3Space Fastrak transmitter was placed above the head, to measure the orientation and position of the head in three dimensions. The 3Space Fastrak has been found, in previous studies, to be reliable in recording positioning among both neck pain patients and healthy subjects. The high load task consisted of the same test, with subjects lying in a supine position. Subjects who were unable to hold their heads for at least 10 seconds were excluded from the study.

In addition to the system measurements, researchers also measured subjects’ subjective assessments of pain and dizziness. Participants in each group rated the intensity of any neck pain they experienced during the testing on a scale of 0-10, and levels of dizziness on a scale of 1-5. The results showed significant differences between the whiplash patients and both the chronic neck pain patients and the healthy controls. Researchers wrote: “The whiplash group showed significantly decreased head steadiness in the low load task compared with the other two groups. The difference was explained largely by severe levels of neck pain and dizziness.”

Healthy volunteers were not expected to show fatigue in the testing, and the results confirmed that steadiness gradually increased for control subjects throughout the low load task. Among the WAD subjects, in contrast, unsteadiness persisted throughout the testing, and in fact, the whiplash group was far less able to maintain head steadiness than the other two groups.

The inclusion criteria ensured that the two pain groups differed only by the history of trauma. Yet the differences in performance on the low load task and levels of neck pain and dizziness while performing that task was significant. This study suggests that whiplash patients suffer from reduced head steadiness related to their history of trauma.

Because balance issues can complicate recovery, it’s important to identify these problems early on so that proper treatment can help prevent long-term complications.

Woodhouse A, Liljebäck P, Vasseljen O. Reduced Head Steadiness in Whiplash Compared with Non-traumatic Neck Pain. Journal of Rehabilitative Medicine 2010;42:69–75.