Thursday, July 15, 2010

Just got back from Vancouver

I was at the AAJ convention and gave a talk on "Using Medical Literature in the Back and Neck Case." We all have handled the whiplash case. We all have heard the "whiplash injuries heal", "pre existing condition", "pain is subjective" and the "impact was too low to have caused an injury" defense in automobile accident cases.

Well, these peer reviewed medical articles refute those defenses. Take a look at my presentation and give me a call if you have any questions.

Can Back & Neck Injuries Be Permanent or Do They All Heal After 18 Months?

Defense Medical Examiner Report Stating That Back & Neck Injuries Cannot Be Permanent

“ The patient’s clinical examination at this time is unremarkable and does not define any objective abnormalities which would correlate with this patient’s complaint.”

“ This patient has a soft tissue or muscle strain type of mechanism. Such conditions are purely subjective in nature and routinely heal over time. Such healing typically occurs in a period of several months and even offering the patient the broad benefit of the doubt, there would be no way that a muscular pain mechanism could be attributed to a traumatic event in excess of eighteen months.”

“ It’s my opinion that this patient’s pain syndrome beyond May 2007 would no longer be attributed to any soft tissue injuries that occurred as a result of the accident.”

Macnab, Ian, M. B., Ch.B., F.R.C.S., Symposium on Disease of the Intervertebral Disc., The "Whiplash Syndrome", Orthopedic Clinics of North America, Vol. 2 No. 2, July 1971.

 266 patients were followed up more than 2 years after claims resolved
 121 patients (45%) continued with neck or back symptoms
 Settlement of legal claims didn’t relieve symptoms in 45% of the patients

Hohl, Mason, MD.., Soft Tissue Injuries of the Neck in Automobile Accidents, The Journal of Bone and Joint Surgery, Vol. 56A, No. 8, December 1974.

 146 patients who had no pre-existing neck problems were followed up more than five years after soft tissue injury
 44 people had no claim for damages
 63 patients (43%) had residual problems because of soft tissue injury of the neck
 A significant % had symptoms well after their claims had been resolved

Norris and Watt, The Prognosis of Neck Injuries Resulting From Rear-End Vehicle Collisions, The Journal of Bone and Joint Surgery, Vol. 65-B, No. 5, November 1983

 61 patients were followed 2 years post-accident in 3 groups
 Group 1: pain complaints with normal exam
 Group 2: pain complaints, reduced ROM
 Group 3: pain complaints, reduced ROM and objective neurological loss
 56% of Group 1, 19% of Group 2 and 10% of Group 3 were pain free at the 2 year mark
 20% of patients in all groups with persistent neck pain lost time from work
 70% of patients in Group 3 and 25% in Group 1 with persistent neck pain said it interfered with hobbies and recreation

Deans, G.T., Magalliard, J.N., Kerr, M. and Rutherford, W.H., Neck sprain-a major cause of disability following car accidents, Injury: The British Journal of Accident Surgery (1987) Vol. 18/No. 1, 10-12

 137 patients with neck injury were followed up between 1 and 2 years post-accident
 36 (26.3%) still had pain with 31 (22.6%) having occasional pain and 5 (3.7%) experiencing severe continuous pain
 “The resulting pain (from soft-tissue injury of the neck) may continue for a long time and seriously disrupt the working and social activities of patients.”

Maimaris, C., Barnes M. R., Allen, M. J., 'Whiplash injuries' of the neck: a retrospective study, Injury: The British Journal of Accident Surgery (1988) Vol. 19/No. 5, 393-396

 102 patients were followed up 2 years post- accident for neck injury
 67 patients were asymptomatic while 35 patients (33%) continued to suffer disability
 In the asymptomatic patients, pain resolved within 2 months; pain persisting more than 2 months usually was chronic
 Many symptomatic patients continued to have pain after resolution of legal claims

Hodgson, S. P. and Grundy, M., Whiplash Injuries: Their Long-term Prognosis and Its Relationship to Compensation, Neuro-Orthopedics 7, 88-91 (1989)

 40 patients were followed 10 - 15 years post-accident for neck injuries
 31% had long term neck problems and only 10 out of 40 improved after resolution of their claims
 44% had to change work duties and 62.5% had to modify leisure activities
 12.5 years after injury, 66% had significant residual problems, even after resolution of legal claims


 “ We would conclude that a whiplash injury has a significant likelihood of resulting in long-term symptoms which in the majority of cases may be physical in nature, and that the settlement of compensation is unlikely to affect the long-term outcome.’

Gargan, M. F., Bannister, G. C., Long-Term Prognosis of Soft-Tissue Injuries of the Neck, The Journal of Bone and Joint Surgery (1990), Vol. 72-B, No. 5, 901-903

 43 patients of Norris and Watt were followed 8 - 12 years after injury
 Only 12% had recovered completely: 28% had symptoms that affected daily activities and 12% had severe symptoms
 74% had neck pain at follow-up at a mean of 10.8 years
 Most patients reach their final condition within 2 years of injury
Hildingsson and Toolanan, Outcome after soft-tissue injury of the cervical spine, Acta Orthop Scand 1990:61 (4): 357 – 359

 93 patients were followed post-accident
 After 2 years, 42% of neck injury patients had recovered, 15% had minor discomfort and 43% had pain which interfered with their ability to work
 This means that 58% had long term neck pain on a chronic basis

Robinson, D.D., Cassar-Pullicino, V.N., Acute neck sprain after road traffic accident: a long-term clinical and radiological review, The Journal of Bone and Joint Surgery (1993), Vol. 24, No. 2, 79-82

 21 patients were followed 10 - 19 years after cervical injury
 86% had persistent neck symptoms
 There was no correlation between conclusion of legal claims and resolutions of symptoms

Parmar, H.V. and Raymakers, R., Neck injuries from rear impact road traffic accidents: prognosis in persons seeking compensation, Injury: The British Journal of Accident Surgery (1993) Vol. 24/No. 2, 75-78

 100 patients with neck injuries were followed between 8 months and 3 years post-accident
 45% were symptom free but 18% had significant pain and disability 3 years after injury
 Compensation neurosis is not likely to develop based on this study

Sturzenegger, M., Radanov, B., Di Stefano, G., The effect of accident mechanisms and initial findings on the long-term course of whiplash injury, JNeurol (1995) 242:443-449

 117 patients were followed after 1 year: 24% still had symptoms
 Factors that led to a worse prognosis were:
1 Rear end collision
2 Unprepared for collision
3 Rotated head position

Radanov, B., Sturzenegger, M., Di Stefano, G., Long-Term Outcome after Whiplash Injury: A 2-Year Follow-Up Considering Features of Injury Mechanism and Somatic, Radiologic, and Psychosocial Findings, Medicine September 1995 Vol. 74, No.5, 281-296

 117 patients in a system which did not provide compensation for non-economic losses were followed 2 years post-accident
 96 were asymptomatic and 21 (18%) continued to have symptoms
 Of the 21, 4 were at fault for the accident and 7 were in collisions described as trivial, meaning a minor event

 Conclusions:
1. The amount of damage and the speed of the cars bear little relationship to the injury sustained by the cervical spine
2. Previous attempts to correlate amount of damage and speed to clinical outcome have been shown to have little prognostic value
3. Those who were in rear-end collisions and unprepared for impact, with heads rotated fared worse over time

Pettersson K, Hildingsson C, Toolanen G, et al. Disc pathology after whiplash injury: a prospective magnetic resonance imaging and clinical investigation. Spine 1997;22(3):283-288

 39 patients were examined by MRI in order to assess initial soft tissue damage, the development of disc pathology and relationship of pathology to symptoms
 2 years after injury, 17 (44%) had either daily or intermittent symptoms, including headache, neck pain, memory and concentration problems
 12 had neurologic deficit on exam

SPINE: State of the Art Reviews 1993: Cervical Flexion-Extension/Whiplash Injuries; Vol.7, No. 3

Do All Plaintiffs Have Pre-Existing Conditions or Just the Ones I Represent?

The defense medical examiner says the pre-existing condition is the cause of the impairment, not the motor vehicle collision

“ The plaintiff’s degenerative cervical and lumbar spine arthritis and her degenerative hip arthritis pre-existed her motor vehicle accident. They have progressed since that time, as would be expected given the natural history of degenerative arthritis.”

Boden, Scott D., MD.., et al., Abnormal Magnetic Resonance Scan of the Lumbar Spine in Asymptomatic Subjects, Journal of Bone and Joint Surgery, March, 1990, Vol. 72-A, No.3 403-408

 MRI performed on 67 patients who had no history of back pain
 20% of those less than 60 years old had a herniated disk
 57% of those 60 years and older had abnormal scans, including disk degeneration, bulging and herniation

 CONCLUSION: A substantial percentage of asymptomatic individuals exhibited abnormal findings on MRI, including degenerative disk disease, bulging and herniation
 35% of those between 20 and 39 years old had bulging or degenerative disks

Jensen, Maureen C., MD.., et al., Magnetic Resonance Imaging of the Lumbar Spine in People Without Back Pain, New England Journal of Medicine, Vol. 331, No. 2, July, 1994, 69-73

 MRI was performed on 98 asymptomatic individuals
 64 % of these asymptomatic individuals had abnormal disk pathology
 52% had a bulge at at least one level, 27% had a protrusion and 1% had an extrusion
 38% had an abnormality of more than one disk

 CONCLUSION: On MRI, a majority of individuals without history of back pain have significant back pathology, including bulging and protrusion

Wood, Kirkham B., MD.., et al., Magnetic Resonance Imaging of the Thoracic Spine: Evaluation of Asymptomatic Individuals, Journal of Bone and Joint Surgery, November, 1995, Vol. 77-A, No.11, 1631-1638

 90 individuals were examined by MRI: 60 had no history of any thoracic or lumbar pain, 30 had history of low back pain only
 73% (66 people) of the asymptomatic group had positive findings, including 33 with herniation (37%), 48 with bulging disk (53%) and 52 with an annular tear (58%)

 Conclusion: This study documents that there is a high prevalence of abnormal disk pathology, including disk herniation and deformation of the spinal cord, when asymptomatic individuals are examined by MRI; further, there was no association between age and prevalence of disk herniation

Boos, Norbert, MD.., 1995 Volvo Award in Clinical Sciences, The Diagnostic Accuracy of Magnetic Resonance Imaging, Work Perception, and Psychosocial Factors in Identifying Symptomatic Disc Herniations, Spine 1996; 20(24): 2613-2625

 The objective of this study was to determine the frequency of disk herniation in asymptomatic individuals
 46 patients with prior discectomy were compared with 46 age, sex and risk factor matched asymptomatic individuals
 76% of the asymptomatic persons had herniation
 51% had bulging and 85% in all had degeneration

 CONCLUSION: In risk factor matched groups, 76% of asymptomatic individuals had disk herniation, which was a much higher incidence than expected. This is evidence that pre-existing DJD may not be symptomatic in a large majority of those persons with DJD and therefore not causal of post collision disability

Since Pain is Subjective, It Must Not Be Real

The Defense Medical Examiner Finds No Objective Signs of Injury And The Patient’s Symptoms Are Purely Subjective In Nature

 “ The patient’s clinical exam is unremarkable and does not define any objective abnormalities which would correlate with this patient’s complaint.”
 “Soft tissue conditions are purely subjective in nature and routinely heal over time.”
 “Such healing typically occurs in a period of several months and even giving the plaintiff the benefit of the doubt, there would be no way that a muscular pain mechanism could be attributed to a traumatic event in excess of eighteen months.”
Scarry E. “The Body In Pain” 1985

 “To have great pain is to have certainty; to hear that another person has great pain is to have doubt.”

Guides to the Evaluation of Permanent Impairment 6th Edition, American Medical Association 2008, Ch. 3 "Pain Related Impairment", pg. 32

The International Association for the Study of Pain defines pain as an unpleasant sensory and emotional experience with actual or potential tissue damage that is described in terms of such damage

The following concepts are embodied in these definitions:

1. Pain is subjective

2. Its presence cannot be readily validated or objectively measured

3. Pain can exist without tissue damage

4. There is no biologic measure that correlates highly with a persons’ complaints of pain

Guides to the Evaluation of Permanent Impairment 4th Edition, American Medical Association 1995, Ch. 15 "Pain"

 Pain is endemic in the population of the USA
 Knowledge, understanding, diagnosis and treatment of chronic pain is rudimentary at best
 Pain encompasses a multifaceted concept that transcends the traditional medical model of disease
 Pain is subjective and its presence cannot be validated or measured objectively
 A 1987 Social Security Administration report said that it is impossible to understand the pain suffered by another individual
 The federal government recognizes the impact of pain: The DHHS has concluded that chronic pain is not a psychiatric disorder
When considering pain, the following assumptions must be considered:
1. Pain cannot be evaluated by strict laboratory standards
2. Chronic pain cannot be measured or detected on the basis of the classic tissue orientated disease model
3. Pain compromises the quality of life of many individuals

18 Q. You would agree that a person who is experiencing
19 the pain is in the best position to know what
20 they're experiencing?
21 A. Certainly.
22 Q. You've had pain before?
23 A. I've got it right now. I was digging post holes
24 this morning.
25 Q. And pain is real, isn't it
1 A. It is.
2 Q. And although you call it subjective, it's really not
3 subjective to the person experiencing the pain, is
4 it?
5 A. It is. Well, if they have it, it is not, correct.

23 Q. And in terms of how much pain an individual's
24 experiencing, again, they're in the best position to
25 know?
1 A. Absolutely.
2 Q. How frequent the pain is, they're in the best
3 position to know?
4 A. Yes.
5 Q. How long they've had pain, they're in the best
6 position to know?
7 A. Yes.
8 Q. When they have pain, meaning what they're doing,
9 what exacerbates the pain, what causes the pain,
10 they're in the best position to know?
11 A. Yes, sir.
12 Q. You would agree that pain can exist without tissue
13 damage?
14 A. Certainly it can.
18 Q. And you would agree it's impossible to understand
19 the pain that another person is experiencing?
20 A. It is.

A Review and Methodologic Critique of the Literature Refuting Whiplash Syndrome
Michael D. Freeman DC, PhD, Arthur Croft DC, MS, et al
Spine Vol. 24, No. 1 1999
A Review and Methodologic Critique of the Literature Refuting Whiplash Syndrome

 This article critiqued literature that attempts to refute the existence of whiplash injuries
 20 articles were evaluated for scientific credibility
 Flaws included:
 Inadequate sample size & study design
 Selection bias
 Unsupported conclusions
 Misquoted literature
 Misuse of terms

Lithuanian Study Concludes Whiplash Is Not Chronic, Based on a Sample of 202 People

 Inadequate sample size: 31 of 202 people, or 15%, were injured initially and as a result, exposed to the potential of chronic whiplash
 94% of those injured would have to be chronic to be significant
 At least 3000 people would have to be in the study in order to have sufficient statistical validity to discern a significant difference between the study group and the control group

Singapore Study of 22 Whiplash Patients Compared With 300 Australian Patients

 Study flawed because numbers were disparate and studies used different enrollment criteria and protocol
 Aussies had chronic whiplash vs. Chinese who had acute whiplash
 20 participants is an inadequate sample size
 Selection bias showed by comparing long term sufferers with those suffering from acute injury

Quebec Task Force on Whiplash-Associated Disorders

 Study concluded that whiplash injuries are short-lived & temporary, pain resulting from whiplash is not harmful, and whiplash prognosis is favorable
 Recovery was defined as “cessation of time-loss compensation”
 Studies that were cited as supporting cure actually supports permanency: Norris & Watt, Radanov & Hildingsson
Crash Test Studies : McConnell
 4 subjects were exposed to rear-end impacts at very low speed
 In a later study, 7 subjects were exposed to rear-end impacts at up to 6.8 MPH
 Conclusion:
 Injury to the low back is unlikely in low impact collision and any injury to the neck is mild and transient at best

Crash Test Studies : Szabo
 5 subjects were subjected to rear-end impacts at 10 MPH
 None had symptoms that lasted longer than 2 days
 A later study of 5 subjects at a speed of 9 MPH was done
 Conclusion: Collisions at 10 MPH or less are within human tolerance and injury is unlikely after a collision at or below 10 MPH
 5 subjects were subjected to rear-end impacts at 10 MPH
 None had symptoms that lasted longer than 2 days
 A later study of 5 subjects at a speed of 9 MPH was done
 Conclusion: Collisions at 10 MPH or less are within human tolerance and injury is unlikely after a collision at or below 10 MPH

Crash Test Studies : Castro

 17 rear impact subjects with an average speed of 7.1 MPH

 The “limit of harmlessness” for rear end impacts is between 6.2 and 9.4 MPH

Errors: Inadequate Study Size

 These studies contained an inadequate number of volunteers
 Example: If a coin is tossed 3 times and comes up heads, is it going to come up heads if tossed 100 times?
 To describe the range of injury in the general population, thousands of subjects need to be included in the crash tests
Errors: Nonrepresentative Study Sample and Crash Conditions
 Subjects include the authors of the studies, employees, friends and other associates of the authors
 Almost all of the subjects were male and none had pre-existing conditions
 The study subjects were healthy males, prepared for impact and perfectly situated in the seat at the time of impact
Biomechanical Studies: Allen
 The forces in a low impact collision are less than those of “plopping down in a chair” or “stepping off of a curb”
 As a result, low and no-damage collisions are unlikely to cause injury

Error: Unsupported Conclusions

 Plopping in a chair and stepping off a curb are not comparable with the movement of the body in a rear-end collision
 The majority of acceleration in a rear-end collision is in a front to back direction
 Whiplash trauma produces a peak accelerative force that is more than 150 times greater than that produced by plopping in a chair

Error: Inappropriate Study Design

 Common movements that do not usually cause injury were compared to whiplash trauma that results in 2.9 million injuries each year
 Neither whiplash injuries nor the mechanism of whiplash injuries were studied

Type of Error by Number and % of Studies

 Nonrepresentative Crash Conditions: 12 (60%)
 Inadequate Sample Size: 12 (60%)
 Nonrepresentative Study Sample: 10 (50%)
 Inappropriate Study Design: 9 (45%)
 Unsubstantiated Claims: 3 (15%)
 Unsupported Conclusions: 5 (25%)
 Misquoted Literature: 1 (5%)
 Improper Use of Terminology: 1 (5%)
 Misleading Illustration: 1 (5%)
 50% of the studies had 3-4 errors each

There Is No Basis For the Following Conclusions

 Acute whiplash injuries do not lead to chronic pain
 Chronic pain due to whiplash is usually psychogenic
 Whiplash injuries are unlikely to result in chronic pain in counties that do not have compensation for injury
 No damage rear impact collisions are unlikely to cause injury
 Whiplash trauma is comparable to movements of daily livings

There Is No Basis For the Following Conclusions

 There is insufficient force to the TMJ during whiplash trauma to cause injury
 TMJ injuries are not associated with whiplash
 There is a direct relationship between amount of damage and likelihood of chronic pain
 Pain caused by whiplash is caused/worsened by treatment and diagnosis
 The risk of chronic neck pain among whiplash patients is the same as the prevalence in the general population

Human Tolerance Levels
A/K/A: Injury Thresholds

Freeman, et al:Significant Spinal Injuries Resulting From Low-Level Accelerations: A Case Series of Roller Coaster Injuries, Arch Phys Med Rehab November 2005;86:2126-30

 Theory: injury to neck can’t occur below a peak head acceleration “injury threshold”
 These are derived from experiments involving human volunteers and cadavers
 Authors measured peak head acceleration on roller coaster riders
 Conclusion:peak head acceleration is a poor indicator of the injuriousness of the event
 Instead, there is no established minimum threshold of spinal injury
 Greatest factor? Individual susceptibility to injury
 “Significant spinal injury can result from low-level accelerations”

Croft and Freeman, Correlating Crash Severity With Injury Risk, Injury Severity and Long Term Symptoms in Low Velocity Motor Vehicle Collisions, Med Sci Monit, 2005 Oct; 11(10): RA 316-21

 Authors looked thru multiple databases for peer reviewed studies comparing injury risk, injury severity or duration of symptoms with structural damage to cars in crashes < 25 MPH
 This was because insurers take position that if PD < $1000, claimant can’t be hurt (MIST)
 Conclusion: substantial number of injuries are reported in crashes without significant PD
 Thus, PD is not a predictor of injury risk or symptom duration
 Head restraint, awareness of crash, sex, prior injury are better predictors of short and long term injury
 “Property damage is an unreliable predictor of injury risk or outcome in low velocity cases”

SAE J885 Revised December 2003

 “Factors involved in the determination of human tolerance levels are…beyond the state of the art in biomechanics except perhaps for a few academic situations”
 Difficulties in establishing human tolerance levels:
 The specific degree of injury severity that should serve as the tolerance level
 Large differences exist in the tolerances of different people
 Tolerance levels are sensitive to modest changes in the direction, shape and stiffness of the loading source

2600 N. Mayfair Road


fiona said...

hi, its very informative, Neck Injury , thanks

Eminia said...

Its such a great informative post..Thanks for the post. Closed Loop Recycling

Whiplash Accident said...

This was an informative and well written blog. I might add that there is a great deal of concern over air embolism, because the intravenous tubing and fluid bags and the way they are utilized creates a high risk.