Sleep, Awareness, 
Motor Vehicle Collisions,
and Chiropractic Care 

In the October 31, 2019 issue of the financial-political magazine Forbes, there is a brief article recommending the reading of a book on sleep by Dr. Matthew Walker. The author of the article is John Doerr, a venture capitalist with Kleiner Perkins. Mr. Doerr prefaces his review by noting that “Leaders from the worlds of business, academia and entertainment and politics share what’s on their bedside tables,” and it is this book by Matthew Walker (1). Matthew Walker, PhD, is a professor of neuroscience and psychology at the University of California, Berkeley. He is also the director of the Center for Human Sleep Science at UC Berkeley. In 2017, Dr. Walker wrote the book (2):

Why We Sleep Unlocking the Power of Sleep and Dreams

This is a fascinating book on neurology and brain neurochemistry and how they influence whole-body health. He notes that every organ in the body and every process in the brain is enhanced with optimal sleep. But he also notes that sleep loss is epidemic in modern developed nations and that sleep loss is the greatest public health challenge we face. He states:

“Sleep is the single most effective thing we can do to reset our brain and body health each day.”

Much of Dr. Walker’s book pertains to the adverse consequences of too little sleep, including:

• Demolishes your immune system, doubling one’s risk of cancer
• Increases Alzheimer’s disease
• Disrupts blood sugar creating pre-diabetes
• Damages arteries, increasing blood pressure and the risks of heart attack and stroke
• Contributes to all major psychiatric conditions, including: depression/anxiety/suicide
• Makes you hungry, resulting in overeating and obesity
• Impairs our ability to learn, memorize, make logical decisions and choices
• Harms our ability to modify (inhibit) painful memories (PTSD)
• Inhibits creativity
• Shortens telomeres and therefore shortens both the quantity and quality of life, stating: “The shorter your sleep, the shorter the life span.”

Pertinent to this discussion, too little sleep causes hundreds of thousands of traffic accidents yearly, exceeding alcohol and drug caused accidents combined. Dr. Walker makes these points pertaining to too little sleep and motor vehicle collisions:

There are deadly consequences of “getting behind the wheel of a motor vehicle without having sufficient sleep.”

“Drowsy driving is the cause of hundreds of thousands of traffic accidents and fatalities each year.”

“Tragically, one person dies in a traffic accident every hour in the United States due to [sleep] fatigue-related error.”

“There are many ways in which lack of sufficient sleep will kill you. Some take time; others are far more immediate. One brain function that buckles under even the smallest dose of sleep deprivation is concentration. The deadly societal consequences of these concentration failures play out most obviously and fatally in the form of drowsy driving.”

“In a disturbing study, researchers took two groups of healthy adults, one of whom they got drunk to the legal driving limit (.08 percent blood alcohol), the other of whom they sleep-deprived for a single night. Both groups performed the concentration test to assess attention performance, specifically the number of lapses. After being awake for nineteen hours, people who were sleep-deprived were as cognitively impaired as those who were legally drunk. Said another way, if you wake up at seven a.m. and remain awake throughout the day, then go out socializing with friends until late that evening, yet drink no alcohol whatsoever, by the time you are driving home at two a.m. you are as cognitively impaired in your ability to attend to the road and what is around you as a legally drunk driver. In fact, participants in the above study started their nosedive in performance after just fifteen hours of being awake (10 p.m. in the above scenario).”

“Car crashes rank among the leading causes of death in most first-world nations. In 2016, the AAA Foundation in Washington, DC, released the results of an extensive study of over 7,000 drivers in the US, tracked in detail over a two-year period. The key finding reveals just how catastrophic drowsy driving is when it comes to car clashes. Operating on less than five hours of sleep, your risk of a car crash increases threefold. Get behind the wheel of a car when having slept just four hours or less the night before and you are 11.5 times more likely to be involved in a car accident. Note how the relationship between decreasing hours of sleep and increasing mortality risk of an accident is not linear, but instead exponentially mushrooms. Each hour of sleep lost vastly amplifies that crash likelihood, rather than incrementally nudging it up.”

“Drunk driving and drowsy driving are deadly propositions in their own right, but what happens when someone combines them? It is a relevant question, since most individuals are driving drunk in the early-morning hours rather than in the middle of the day, meaning that most drunk drivers are also sleep-deprived.”

“We can now monitor driver error in a realistic but safe way using driving simulators. A group of researchers examined the number of complete off-road deviations in participants placed under four different experimental conditions.”:

1) 8 hours of sleep: zero to few off-road errors.

2) 4 hours of sleep: six times more off-road deviations then sober well-rested individuals.

3) 8 hours of sleep plus alcohol to the point of being legally drunk: six times more off-road deviations then sober well-rested individuals (the same as only 4 hours of sleep) “Driving drunk or driving drowsy were both dangerous, and equally dangerous.”

4) 4 hours of sleep plus alcohol to the point of being legally drunk:

“A reasonable expectation was that performance in the fourth group of participants would reflect the additive impact of these two groups: four hours of sleep plus the effect of alcohol (i.e., twelve times more off-road deviations) It was far worse. This group of participants drove off the road almost 30 times more than the well-rested, sober-group.” “The heady cocktail of sleep loss and alcohol was not additive, but instead multiplicative. They magnified each other, like two drugs whose effects are harmful by themselves but, when taken together, interact to produce truly dire consequences.”

“After thirty years of intensive research, we can now answer many of the questions posed earlier. The recycle rate of a human being is around sixteen hours. After sixteen hours of being awake, the brain begins to fail. Humans need more than seven hours of sleep each night to maintain cognitive performance. After ten days of just seven hours of sleep, the brain is as dysfunctional as it would be after going with¬out sleep for twenty-four hours.”

“The real-life consequences of drowsy driving deserve special mention. This coming week, more than 2 million people in the US will fall asleep while driving their motor vehicle. That’s more than 250,000 every day, with more such events during the week than week¬ends for obvious reasons. More than 56 million Americans admit to struggling to stay awake at the wheel of a car each month.”

“As a result, 1.2 million accidents are caused by sleepiness each year in the United States. Said another way: for every thirty seconds you’ve been reading this book, there has been a car accident somewhere in the US caused by sleeplessness. It is more than probable that someone has lost their life in a fatigue-related car accident during the time you have been reading this chapter.”

“You may find it surprising to learn that vehicle accidents caused by drowsy driving exceed those caused by alcohol and drugs combined. Drowsy driving alone is worse than driving drunk. Drunk drivers are often late in braking, and late in making evasive maneuvers. But when you fall asleep, or have a microsleep, you stop reacting altogether.”

“A person who experiences a microsleep or who has fallen asleep at the wheel does not brake at all, nor do they make any attempt to avoid the accident. As a result, car crashes caused by drowsiness tend to be far more deadly than those caused by alcohol or drugs. Said crassly, when you fall asleep at the wheel of your car on a freeway, there is now a one-ton missile traveling at 65 miles per hour, and no one is in control.”

“Drivers of cars are not the only threats. More dangerous are drowsy truckers. Approximately 80 percent of truck drivers in the US are over¬weight, and 50 percent are clinically obese. This places truck drivers at a far, far higher risk of a disorder called sleep apnea, commonly associ¬ated with heavy snoring, which causes chronic, severe sleep depriva¬tion. As a result, these truck drivers are 200 to 500 percent more likely to be involved in a traffic accident. And when a truck driver loses his or her life in a drowsy-driving crash, they will, on average, take 4.5 other lives with them.”

“In actual fact, I would like to argue that there are no accidents caused by fatigue, microsleeps, falling asleep. None whatsoever. They are crashes. The Oxford English Dictionary defines accidents as unexpected events that happen by chance or without apparent cause. Drowsy-driv¬ing deaths are neither chance, nor without cause. They are predictable and the direct result of not obtaining sufficient sleep. As such, they are unnecessary and preventable. Shamefully, governments of most devel¬oped countries spend less than 1 percent of their budget educating the public on the dangers of drowsy driving relative to what they invest in combating drunk driving.”

“There are many things that I hope readers take away from this book. This is one of the most important: if you are drowsy while driving, please, please stop. It is lethal. To carry the burden of another’s death on your shoulders is a terrible thing. Don’t be misled by the many ineffective tactics people will tell you can battle back against drowsiness while driving. Many of us think we can overcome drowsiness through sheer force of will, but, sadly, this is not true. To assume otherwise can jeopardize your life, the lives of your family or friends in the car with you, and the lives of other road users. Some people only get one chance to fall asleep at the wheel before losing their life.”

“One of the ironic statistics concerning drowsy driving. When a sleep-deprived [medical] resident finishes a long shift, such as a stint in the ER trying to save victims of car accidents, and then gets into their own car to drive home, their chances of being involved in in a motor vehicle accident are increased by 168 percent because of fatigue.”

“After twenty-two hours without sleep, human performance is impaired to the same level as that of someone who is legally drunk.”

“The leading cause of death among teenagers is road traffic accidents.”

“The leading cause of death among teenagers is road traffic accidents, and in this regard, even the slightest dose of insufficient sleep can have marked consequences.”

“When the Mahtomedi School District of Minnesota pushed their school start time from 7:30 to 8:00 a.m., there was a 60 percent reduction in traffic accidents in drivers sixteen to eighteen years of age.”

“Teton County in Wyoming enacted an even more dramatic change in school start time, shifting from a 7:35 a.m. bell to a far more biologically reasonable one of 8:55 a.m. The result was astonishing—a 70 percent reduction in traffic accidents in sixteen- to eighteen-year-old drivers.”

“These publicly available findings should have swept the education system in an uncompromising revision of school start times. Instead, they have largely been swept under the rug.”

In his book, Dr. Matthew Walker describes the relationships between drowsy driving, automobile collisions, and loss of life. For chiropractors, critically important to the discussion is automobile collision injuries. As described by Dr. Walker, drowsy driving is more hazardous than drunk driving. Drunk driving slows protective responses, increasing the risks of collisions. Drowsy driving causes microsleep or full-on sleep, eliminating all protective responses. During microsleep or full-on sleep the driver is caught completely unaware of the impending collision: In 1990, an article published in the journal of the Society of Automotive Engineers, titled Whiplash in Low Speed Vehicle Collisions notes (3):

“If the passenger is aware of and anticipates a collision, and makes his neck muscle tense, he can tolerate more severe impact.”

In 1992, the book Painful Cervical Trauma notes (4):

“Injury results because the neck is unable to adequately compensate for the rapidity of head and torso movement resulting from the acceleration forces generated at the time of impact. This is particularly true when the impact is unexpected and the victim is unable to brace for it.”

In 1993, an article published in the journal Trial Talk, titled The Physics, Biomechanics and Statistics of Automobile Rear Impact Collisions, notes (5):

“Research has shown that an occupant aware of an impending impact may possess sufficient muscle control to prevent hyperflexion and hyperextension during low velocity impacts.”

In 1993, the journal/book Spine: State of the Art Reviews, Cervical Flexion-Extension/Whiplash Injuries, notes (6):

In the whiplash acceleration-deceleration injury, muscle response might arrest, limit, or control the movements of a cervical motion segment. “Without muscle control the normal arcuate movement of a cervical motion segment must be disturbed, and the forces to which individual segments are subjected can be resisted only by passive ligamentous elements or bony contact. This sets the scene for a variety of possible injuries.”

In the same 1993 journal/book, another author notes (7):

“…when the impact is unexpected and the victim is unable to brace.”

In 1994, a research article evaluating 137 whiplash-injured subjects was published in Neurology, titled Presenting Symptoms and Signs after Whiplash Injury: The influence of Accident Mechanism, notes (8):

“Patients struck when they were unprepared for the impact had a significantly higher frequency of multiple symptoms, higher headache intensity, and shorter latency of headache onset.

The state of preparedness “proved to be the first significant factor with respect to initial injury findings.”

Also in 1994, research published in the journal Injury, titled Neck Strain in Car Occupants: Injury Status After 6 Months and Crash-related Factors, notes (9):

“...awareness appears to have a strong protective influence and may prove to be a useful prognostic indicator in clinical settings.

...subjects who were unaware of the impending collision had a greatly increased likelihood of experiencing persisting symptoms and/or signs of neck strain, compared to those who were aware.

Subjects who were unaware of the impending collision were 15 times more likely to have a persisting condition than those who were aware.”

In 1995, a follow-up to the 137 whiplash-injured study (#8) was published in the Journal of Neurology, titled The Effect of Accident Mechanism and Initial Findings on the Long-term Course of Whiplash Injury, again notes

“...unpreparedness at the time of impact…” is the most significant in poor outcome from a whiplash injury (10):

In 1998, primary research published in the journal Archives of Physical Medicine and Rehabilitation, titled Clinical Response of Human Subjects to Rear-end Automobile Collisions, notes that if the patient is caught by surprise during a rear-end collision, the threshold for injury begins at a change in velocity of only 2.5 mph (11). In 2014, an article published in the journal PET and SPECT in Neurology, titled Whiplash: Real or Not Real?: A Review and New Concept, notes (12):

In some patients who experience an unexpected rear-end collision, the “symptoms persist for years.”

An essential factor in chronic whiplash symptoms is the “unexpectedness of the accident.”

“Whether or not the driver in a rear-end crashed car is aware of the impending collision is extremely important.”

“The awareness or expectancy of the incoming collision is crucial in the whiplash process;” 70-80% of the patients suffering from chronic whiplash “were unaware of the incoming collision.”

“A correlation exists between being unaware of the incoming collision and a poor recovery.”

A crucial factor in determining the extent of a whiplash mechanism injury is the “expectancy of the incoming collision.”

The biological concepts are simple and not controversial. Joints are injured when the muscles that cross the joint do not optimally protect them. Historically, being “caught by surprise” prior to a motor vehicle collision offers no joint protection from the muscles. Chiropractors have known for decades that for many injured patients, perhaps the most important prognostic factor, is understanding the patient’s state of awareness prior to the collision. As such, chiropractors routinely ask about and record the “state of awareness” question on their patients. Similarly, experiencing a microsleep or full-on sleep prior to an automobile collision would eliminate all joint protection from the muscles, increasing joint injury. Perhaps inquiring about sleep status the night prior to and just before an automobile collisions would add valuable injury and prognostic information. Thirty percent of patients who initially seek chiropractic care do so because of neck pain, and their level of satisfaction with their care is quite high (13). Studies support the value of spinal manipulation for the treatment of neck pain and neck injured patients. The biological rationale for spinal manipulation in the treatment of whiplash-injury neck pain includes:

A. The primary injury from whiplash biomechanics is to the facet joints.

B. The primary source of both acute and chronic whiplash injury pain is the facet joints.

C. Spinal adjusting (specific joint manipulation) primarily affects the facet joints.

In support, four studies are briefly presented here: In 1996, clinicians from the University Department of Orthopaedic Surgery, Bristol, United Kingdom, published a study in the journal Injury, titled (14):

Chiropractic Treatment of Chronic ‘Whiplash’ Injuries

They authors note that 43% of patients will suffer long-term symptoms following ‘whiplash’ injury, for which no conventional treatment has proven to be effective. Consequently, they performed a retrospective study to determine the effects of chiropractic spinal manipulation in a group of 28 patients who were suffering with chronic ‘whiplash’ syndrome. The 28 patients in this study had initially been treated with anti-inflammatories, soft collars and physiotherapy. These patients had all become chronic, and were referred for chiropractic at an average of 15.5 months (range was 3–44 months) after their initial injury. At the initial evaluation and prior to chiropractic treatment, 27/28 (96%) of the patients were classified as having intrusive or disabling symptoms. Following the chiropractic treatment, 93% of the patients had improved. The authors concluded:

“The encouraging results from this retrospective study merit the instigation of a prospective randomized controlled trial to compare conventional with chiropractic treatment in chronic ‘whiplash’ injury.”

“The results of this retrospective study would suggest that benefits can occur in over 90% of patients undergoing chiropractic treatment for chronic whiplash injury.”

In 1999, the same group of clinicians from the University Department of Orthopaedic Surgery, Bristol, United Kingdom, published a study in the Journal of Orthopaedic Medicine, titled (15):

A Symptomatic Classification of Whiplash Injury and the Implications for Treatment

This study involved 93 consecutive whiplash-injured patients who were chronic and referred for chiropractic spinal manipulation. Patients underwent a mean of 19.3 treatments (range 1-53), over a period of 4.1 months. The authors note:

“Conventional treatment of patients with whiplash symptoms is disappointing.”

“In chronic cases, no conventional treatment has proved successful.”

“The results from this study provide further evidence that chiropractic is an effective treatment for chronic whiplash symptoms.”

“Chiropractic is the only proven effective treatment in chronic [whiplash] cases.”

In 2004, a group of physiotherapists, physicians, and professors from the Rey Juan Carlos University, Spain, published a study in the Journal of Whiplash & Related Disorders, titled (16):

Manipulative Treatment vs. Conventional Physiotherapy Treatment in Whiplash Injury: A Randomized Controlled Trial

The objective of this clinical trial was to compare the results obtained from a manipulative protocol with the results obtained from a conventional physiotherapy treatment in patients suffering from whiplash injury. This is the first controlled experimental trial documenting the effects of the manipulative protocol used in this study. It was a randomized controlled trial using 380 acute whiplash injury (less than 3 months duration) subjects. The authors note:

“Patients who had received manipulative treatment needed fewer sessions to complete the treatment than patients who had received physiotherapy treatment.”

“Patients of manipulative group needed an average of 9 sessions to complete the treatment, whereas physiotherapy group needed an average of 23 sessions.”

“Results showed that the manipulative group had more benefits than the physiotherapy group.”

“Our clinical experience with these [whiplash-injured] patientshas demonstrated that manipulative treatment gives better results than conventional physiotherapy treatment.”

“This clinical trial has demonstrated that head and neck pain decrease with fewer treatment sessions in response to a manipulative treatment protocol as compared to a physiotherapy treatment protocol among patients diagnosed with acute whiplash injury.”

“Manipulation is “effective in the management of whiplash injury.”

“Manipulative treatment is more effective in the management of whiplash injury than conventional physiotherapy treatment.”

In 2015, researchers and clinicians from the Orthopedic University Hospital Balgrist, University of Zurich, Switzerland, published a study in the Journal of Manipulative and Physiological Therapeutics, titled (17):

Prognostic Factors for Recurrences in Neck Pain Patients Up to 1 Year After Chiropractic Care

This is a prospective cohort study assessing 545 neck pain patients. After a course of chiropractic spinal manipulation, they were followed up for one year regarding recurrence of their neck pain. The results of this study are impressive: Fifty-four (54) participants (11%) were identified as “recurrent.” Four hundred ninety one (491) participants (89%) were not recurrent. The authors state:

“89% of neck pain patients had recovered from their neck pain episode up to 1 year after receiving chiropractic care.”

“The results of this study suggest that recurrence of neck pain within 1 year after chiropractic intervention is low.”

REFERENCES

1. Doerr J; “Book Value”; Forbes; October 31, 2019; p. 26.
2. Walker S; Why We Sleep: Unlocking the Power of Sleep and Dreams; Scribner; 2017.
3. Emori RI, Horiguchi J; Whiplash in Low Speed Vehicle Collisions; SAE; February 1990; p. 108.
4. Teasell RW, McCain GA; in Painful Cervical Trauma; Williams and Wilkins; 1992; p. 293.
5. Smith JJ; The Physics, Biomechanics and Statistics of Automobile Rear Impact Collisions; Trial Talk; June 1993; pp. 0-14.
6. Lord S; in Spine: State of the Art Reviews: “Cervical Flexion-Extension/Whiplash Injuries”; Hanley & Belfus; September 1993; p. 360.
7. Teasell RW, in Spine: State of the Art Reviews: Cervical Flexion-Extension/Whiplash Injuries”; Hanley & Belfus; September 1993; p. 374.
8. Sturzenegger M, DiStefano G, Radanov BP, Schnidrig A; Presenting symptoms and signs after whiplash injury: The influence of accident mechanism; Neurology; April 1994; pp. 688-693.
9. Ryan GA, Taylor GW, Moore VM, Dolinis J; Neck strain in car occupants: Injury status after 6 months and crash-related factors; Injury; September 1994; pp. 533-537.
10. Sturzenegger M, Radanov BP, Di Stefano G; The effect of accident mechanism and initial findings on the long-term course of whiplash injury; Journal of Neurology; 1995; pp. 443-449.
11. Brault JR, Wheeler JB; Clinical response of human subjects to rear-end automobile collisions; Archives of Physical Medicine and Rehabilitation; 1998, Vol. 79; No. 1; pp. 72-80.
12. Garcia DV, Dierckx RAJP, Otte A; Whiplash: Real or Not Real?: A Review and New Concept; PET and SPECT in Neurology; 2014; pp. 947-963.
13. Adams J, Peng W, Cramer H, Sundberg T, Moore C; The Prevalence, Patterns, and Predictors of Chiropractic Use Among US Adults: Results From the 2012 National Health Interview Survey; Spine; December 1, 2017; Vol. 42; No. 23; pp. 1810–1816.
14. Woodward MN, Cook JCH, Gargan MF, and Bannister GC; Chiropractic treatment of chronic ‘whiplash’ injuries; Injury; Vol. 27; No. 9; November 1996; pp. 643-645.
15. Khan S, Cook J, Gargan M, Bannister G; A symptomatic classification of whiplash injury and the implications for treatment; The Journal of Orthopaedic Medicine; Vol. 21; No. 1; 1999; pp. 22-25.
16. Fernández-de-las-Peñas C, Fernández-Carnero J, Palomeque del Cerro L, Miangolarra-Page JC; Manipulative Treatment vs. Conventional Physiotherapy Treatment in Whiplash Injury: A Randomized Controlled Trial; Journal of Whiplash & Related Disorders; 2004; Vol. 3; No. 2.
17. Langenfeld A, Humphreys K, Swanenburg J, Cynthia K. Peterson CK; Prognostic Factors for Recurrences in Neck Pain Patients Up to 1 Year After Chiropractic Care; Journal of Manipulative and Physiological Therapeutics; September 2015; Vol. 38; No. 7; pp. 458-464.

“Authored by Dan Murphy, D.C.. Published by ChiroTrust® – This publication is not meant to offer treatment advice or protocols. Cited material is not necessarily the opinion of the author or publisher.”