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October 2004 Table of Contents
CBP® Research Update • Conventional Wisom • Don's Opinion • CBP® and Geriatrcs: A Case Report • Enough of Chiropractic is for This Pain or That Pain • Chiropractic Passion • The Purpose Driven Practice • Three New and Important Whiplash Articles • You Hired Me To Do A Job • ACA Lawsuit Dismissed • CBP® Online Cyber Update • Harrisons' and Caillet • ICA Files 'Amicus' Brief • A Response to Dr Fuhr • Life University Achieves Financial Goal • Structural Rehab Tool • CBP®'s Chiropractoc of the Year • CBP®'s Annual Awards
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Three New and Important
Whiplash Articles:
Anterior Longitudinal Ligament Injury, Disc Injury, Low Impact Injury
by Daniel J. Murphy, DC, FACO
Vice President of ICA
 Dan Murphy graduated magna cum laude from Western States Chiropractic College in 1978, and has more than 20 years of practice experience. He received Diplomat status in Chiropractic Orthopedics in 1986. Since 1982, Dr. Murphy has served part-time as undergraduate faculty at Life Chiropractic College West, currently teaching classes to seniors in the management of spinal disorders.
Dr. Murphy is on the post-graduate faculty of several chiropractic colleges. His post-graduate continuing education classes include “Whiplash and Spinal Trauma” and “Pain Neurology.” Dr. Murphy is the coordinator of a year-long certification program in “Chiropractic Spinal Trauma,” now (2000) in its twelfth year of being offered. This year, the program is being offered through the International Chiropractors Association of California. He has taught more than 700 post-graduate continuing education seminars.
Dr. Murphy is a contributing author to the book Motor Vehicle Collision Injuries, published by Aspen, 1996; and to the book Pediatric Chiropractic, published by Williams & Wilkins, 1998. He writes a
quarterly column in the Journal of Clinical Chiropractic.
In 1987, 1991 and 1995 Dr. Murphy received the Post-graduate Educator of the Year award, given by the International Chiropractic Association.
In 1997, he received The Carl S. Cleveland, Jr., Educator of the Year award, given by the International Chiropractic Association of California.
In recent years, whiplash research has focused primarily on injury to the facet joint, and on how the facet joint is involved in most cases of chronic post-whiplash pain. The following three studies look at other tissues being injured and resulting in chronic pain.
Injury of the anterior-longitudinal ligament during whiplash simulation
European Spine Journal, January, 2004; 13: 61-68
P. C. Ivancic, A. M. Pearson,
M. M. Panjabi, S. Ito
These authors note:
1) Anterior longitudinal ligament (ALL) injuries following whiplash have been documented both in vivo and in vitro.
2) Whiplash trauma has been linked to chronic neck pain.
3) “Approximately 50% of whiplash patients have reported chronic neck pain 15 years after the trauma.”
4) The lower cervical spine hyperextends during the initial phase of whiplash, causing facet joint compression injuries. This hyperextension may also result in excessive strains in the anterior soft tissues.
5) “There is significant clinical and biomechanical evidence demonstrating that anterior longitudinal ligament (ALL) and anterior annulus injuries often occur simultaneously during whiplash.”
6) Soft tissue injuries of the cervical spine can lead to instability and chronic pain. “Evidence suggests that ALL and anterior annulus injury may lead to clinical instability and pain.”
7) “Subacute instability of the cervical spine has been reported in patients presenting with neck pain and normal radiographs, who subsequently developed clinical instability, most likely due to ligamentous injury.”
8) “Significant increases in the ALL strains in excess of the corresponding physiological strains were first observed at C4-C5 during the 3.5 g trauma.”
9) This study “demonstrated that the greatest ALL strains occurred in the lower cervical spine and that ALL strains increased with impact severity.”
10) The “data suggest that a minority of the population is at risk for complete ALL tears during whiplash.”
11) Annular disc lesions heal poorly. “If ALL and anterior annulus injuries do not completely heal, clinical instability and chronic pain could develop.”
12) “It is likely that some patients with chronic neck pain following whiplash trauma suffer from cervical instability as a result of mechanical disruption of the anterior stabilizing system.”
13) “Injury to the passive anterior column soft tissues could also result in increased loading and degeneration of the posterior spinal components.”
14) Disc degeneration leads to facet osteoarthritis. Radiographic studies show that facet joint osteoarthritis rarely occurs without prior disc degeneration.
15) ALL and anterior annulus injuries sustained in whiplash could lead to increased loading, pain and osteoarthritis of the cervical facet joints.
Key points from this article are:
1) 50% of whiplash patients have reported chronic neck pain 15 years after the trauma.
2) The facet joint is the primary site of chronic whiplash neck pain.
3) Anterior longitudinal ligament (ALL) injuries following whiplash have been documented.
4) These ALL injuries begin at 3.5 g trauma, which is low impact, and occur mostly in the lower cervical spine.
5) The lower cervical spine hyperextends during the initial phase of whiplash, causing facet joint compression injuries and excessive strains in the anterior soft tissues. This can injure the ALL and anterior annulus of the disc.
6) ALL and anterior annulus injury may lead to clinical instability and pain.
7) Annular disc lesions heal poorly.
8) When ALL and anterior annulus injuries do not heal completely, clinical instability and chronic pain develop.
9) Injury to the anterior annulus is followed by fibrosis of the nucleus pulposus, increased loading of the facet joints, and osteoarthritic changes in the facet joints. This may lead to chronic facet joint pain.
10) Disc degeneration results in increased facet loading, which could lead to chronic facet pain.
Injury Mechanisms of the Cervical Intervertebral Disc During Simulated Whiplash
Spine: Volume 29(11)June 1, 2004 pp 1217-1225
Panjabi, Manohar M. PhD; Ito, Shigeki MD; Pearson, Adam M. BA; Ivancic, Paul C.
This study exposed 6 human cadaver spine to whiplash at forces of 3.5, 5, 6.5, and 8 Gs. Increases over sagittal physiologic levels were first observed during the 3.5 g simulation, which was also the lowest level of exposure.
These authors note:
1) The cervical intervertebral discs may be at risk for injury during whiplash.
2) “Approximately 50% of whiplash patients reported chronic neck pain 15 years after the trauma.”
3) “Clinical evidence suggests that disc injury and accelerated degeneration are common in whiplash patients.”
4) “Sufficient clinical evidence exists to support our conclusion that the cervical discs are at risk for acute injury during whiplash.”
5) “Multiple MRI studies have demonstrated posterior and posterolateral disc herniations in whiplash patients immediately following trauma, implying that the anulus fibrosus failed during the impact.”
6) “While acute injury to the cervical disc appears to cause immediate herniation in a minority of whiplash patients, a greater number of patients are vulnerable to accelerated disc degeneration over 5 to 10 years following the whiplash trauma.”
7) “The mechanism of degeneration in these patients is unknown; however, animal studies have demonstrated that small tears in the anulus fibrosus can initiate the disc degeneration process. It seems likely that a similar mechanism may underlie disc degeneration in whiplash patients: the trauma may produce a small tear in the anulus that triggers the biochemical cascade leading to degeneration.”
8) “The presence of nerve endings in the outer anulus fibrosus makes disc injury a plausible etiology of neck pain.”
9) “Clinical studies have implicated the facet joint as the source of chronic pain in approximately 50% of whiplash patients.”
10) “Anulus fibrosus injury can lead to disc degeneration and facet joint osteoarthritis.”
11) A decrease in disc height results in increased loading to the facet joints.
12) “Anulus fibrosus injuries sustained during whiplash could potentially lead to disc degeneration accompanied by increased loading, pain, and osteoarthritis of the cervical facet joints.”
13) “While disc injury may be the cause of acute pain and muscle spasm following the trauma, it could also lead to disc degeneration, facet osteoarthritis, and chronic neck pain.”
Key points from this article are:
1) 50% of whiplash patients reported chronic neck pain 15 years after the trauma.
2) Even low impact rear-end collusions can injure and herniate the cervical discs.
3) The most common site of whiplash disc injury is C5-C6.
4) Whiplash trauma can accelerate disc degeneration, especially in the following 5 to 10 years following the trauma.
5) Small tears in the anulus fibrosus can initiate the disc degeneration process.
6) The anulus of the disc has pain nerve fibers, which makes disc injury a plausible etiology of neck pain.
7) Subfailure injuries to the disc can trigger a reflex arc leading to multifidus contraction and muscle spasm.
8) The facet joint is the source of chronic whiplash pain in about 50% of whiplash patients.
9) Anulus fibrosus injury can lead to disc degeneration, increased loading to the facet joints, and facet joint osteoarthritis.
10) Whiplash disc injury can cause acute neck pain and muscle spasm, and lead to disc degeneration, facet osteoarthritis, and chronic neck pain.
Case Report: Whiplash-Associated Disorder From a Low-Velocity Bumper Car Collision: History,Evaluation, and Surgery
Spine: Volume 29(17) September 1, 2004 pp 1881-1884
Duffy, Michael F. MD; Stuberg, Wayne PhD; DeJong, Stacey MS; Gold, Kurt V. MD; Nystrom, N Ake MD, PhD
This article is a case report of 46-year old patient with a whiplash-associated disorder following a rear-end bumper car collision. The patient suffered with debilitating neck pain and headaches for eight years after this low-velocity collision.
The patient stated that he was not prepared for the impact. His headaches and neck pain developed immediately after the accident and did not improve over subsequent weeks. With a year he was worse and largely disabled. He had never sustained any kind of acute neck trauma before or after this bumper car episode.
X-rays of the cervical spine and left shoulder, MRI of the neck, CT scan of the neck and electromyography, did not identify a cause for the unremitting symptoms.
The x-rays were also negative for evidence of acute injury and showed no degenerative or other chronic changes that could be associated with his headaches or neck pain.
On physical examination, the patient demonstrated limitations in neck mobility with focal tenderness at the posterior cervicothoracic junction. Palpation of several trigger points in that area caused radiating pain along the neck and into the right shoulder. There were no motor, sensory, or deep tendon reflex deficits in either the upper or lower extremities, and there was no clinical evidence of a peripheral compression neuropathy. Yet, the patient developed diffuse paresthesias in the right and left hands and forearms. His writing hand had weakness and poor coordination.
After 8 years, the fascia was surgically resected where small sensory nerves and vessels perforated the structures, resulting in decompression. They did not remove muscle tissue. This surgical treatment resulted in an increase in cervical range of motion by 20%, reduced intake of pain medication, doubled the number of work hours, and generally led to a dramatic improvement in quality of life.
The authors cite two studies that concluded that “rear-end collisions with a delta V of 10-15 km/h [6.2-9.3 m/h] or less cannot result in whiplash associated disorder,” and then cite 3 other studies that disagree with the conclusions of those studies. The authors conclude that “there is no consensus regarding a threshold value for the delta V that can precipitate WAD after low-velocity, rear-end collisions.”
These authors cite a 1997 study that showed cervical range of motion measurements obtained at 3 months serve as valid predictors of permanent disability after a whiplash trauma. Another study notes that cervical range of motion can discriminate between asymptomatic patients and patients with persistent symptoms after whiplash trauma, concluding that such measurements are reliable parameters of physical impairment from whiplash injury.
These authors note:
1) “Imaging studies, including MRI, is not sufficient to exclude significant injury after whiplash trauma to the neck.”
2) “A variety of factors, including the occupant’s awareness or head position in a colliding vehicle, defines the risk of neck injury to passengers in colliding vehicles.”
3) “One can only conclude that the threshold of injury is a complex dynamic relying on velocity, force, head position, head-torso angles, restraint placement, anticipation, tissue elasticity, tissue strength, and any multitude of variables that evade accurate determination.”
4) “The risk of permanent symptoms may be minimal after low-velocity collisions, yet research cannot disregard the clinical possibility of injury based on small studies that fail to simultaneously consider all pertinent variables.”
5) Soft-tissue damage is a more likely cause of chronic whiplash in patients when there are negative imaging studies.
6) “Considering the complex mechanism of trauma, a common pathophysiology is not likely among all individuals with whiplash associated disorders, and their condition must therefore be assessed individually in light of the clinical syndrome and the objective findings.”
7) “This case history illustrates that a low-velocity collision can cause soft-tissue damage in the posterior neck, which may lead to chronic symptoms consistent with whiplash associated disorders.”
8) “The myriad of dynamic variables between occupant and vehicle precludes a definition of change-in-velocity thresholds for neck injury from car collisions.”
9) “Computerized motion analysis is a reliable method to confirm whiplash-associated disorder, quantify the patient’s physical impairment, and identify indications for surgical treatment.”
Key points from this article are:
1) There is no consensus as to the threshold of force required to injure a patient or to cause permanent injury from motor vehicle collisions.
2) Cervical range of motion analysis is important in confirming the diagnosis of whiplash-associated disorder and in the evaluation of prognosis and treatment and permanent disability.
3) The studies that conclude one cannot be injured with delta Vs of less than 15 km/h (9.3 m/h) are wrong.
4) Cervical range of motion measurements obtained at 3 months is a valid predictor of permanent disability after a whiplash trauma.
5) Cervical range of motion can discriminate between asymptomatic patients and patients with persistent symptoms after whiplash trauma.
6) Cervical range of motion measurements is a reliable parameters of physical impairment from WAD.
7) Normal x-rays, MRI, CT, and EMG studies do not mean that one is not injured or impaired or suffering from debilitating chronic symptoms.
8) One can suffer from diffuse extremity paresthesias, motor weakness and poor coordination without a radiculopathy.
9) One can suffer from diffuse extremity paresthesias, motor weakness and poor coordination with normal motor, sensory, and deep tendon reflex examinations.
10) Imaging studies, including MRI, do not exclude significant injury after whiplash trauma to the neck.
11) An occupant’s awareness and/or head position are important factors is assessing the risk of neck injury to passengers in colliding vehicles.
12) Whiplash threshold of injury is a complex dynamic relying on velocity, force, head position, head-torso angles, restraint placement, anticipation, tissue elasticity, tissue strength, and any multitude of variables that evade accurate determination.
13) If imaging studies are negative, the cause of chronic whiplash symptoms is probably soft tissue injury.
14) A low-velocity collision can cause soft-tissue damage in the posterior neck, which may lead to chronic whiplash symptoms.
15) Between the occupant and the vehicle there are so many variables, it is impossible to establish a change-in-velocity thresholds for neck injury from car collisions.
COMMENT
Importantly, the last reference in this article is the 1998 article by Charles Davis, DC. Dr. Davis teaches two modules in the ICA ten module certification program in Spine Trauma that I coordinate (the Certified Chiropractic Spinal Trauma or CCST program). Dr. Davis teaches the module on low impact collisions, and he co-teaches the module on courtroom protocols with attorney Travis Black. Next year the program will be in Dallas. You can sign-up for any class in the series by contacting the ICA at (800) 423-4690. Approximately 1,500 chiropractors have graduated from the ICA’s certification program in Spinal Trauma, achieving their CCST degree.
[Davis CG. Rear-end impacts: vehicle and occupant response. J Manipulative Physiol Ther 1998;21:629-39.]
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