The term "whiplash" was first used
in 1928 to define an injury mechanism of sudden hyperextension
followed by an immediate hyperflexion of the neck that results in
damage to the muscles, ligaments and tendons – especially those that
support the head. Today, we know that whiplash injuries frequently do
not result from hyperextension or hyperflexion (extension and flexion
beyond normal physiological limits), but rather an extremely rapid
extension and flexion that causes injuries.
Due to their complicated nature and profound impact on peoples lives,
few topics in health care generate as much controversy as whiplash
injuries. Unlike a broken bone where a simple x-ray can validate the
presence of the fracture and standards of care can direct a health care
professional as to the best way in which to handle the injury,
whiplash injuries involve an unpredictable combination of nervous
system, muscles joints and connective tissue disruption that is not
simple to diagnose and can be even more of a challenge to treat. In
order to help you understand the nature of whiplash injuries and how
they should be treated, it is necessary to spend a bit of time
discussing the mechanics of how whiplash injuries occur.
The Four Phases of a Whiplash Injury
During a rear-end automobile collision, your body goes through an
extremely rapid and intense acceleration and deceleration. In fact,
all four phases of a whiplash injury occur in less than one-half of a
second! At each phase, there is a different force acting on the body
that contributes to the overall injury, and with such a sudden and
forceful movement, damage to the vertebrae, nerves, discs, muscles, and
ligaments of your neck and spine can be substantial.
Phase 1
During this first phase, your car begins to be pushed out from under
you, causing your mid-back to be flattened against the back of your
seat. This results in an upward force in your cervical spine,
compressing your discs and joints. As your seat back begins to
accelerate your torso forward, your head moves backward, creating a
shearing force in your neck. If your head restraint is properly
adjusted, the distance your head travels backward is limited. However,
most of the damage to the spine will occur before your head reaches
your head restraint. Studies have shown that head restraints only
reduce the risk of injury by 11-20%.
Phase 2
During phase two, your torso has reached peak acceleration - 1.5 to 2
times that of your vehicle itself - but your head has not yet begun to
accelerate forward and continues to move rearward. An abnormal
S-curve develops in your cervical spine as your seat back recoils
forward, much like a springboard, adding to the forward acceleration
of the torso. Unfortunately, this forward seat back recoil occurs
while your head is still moving backward, resulting in a shearing
force in the neck that is one of the more damaging aspects of a
whiplash injury. Many of the bone, joint, nerve, disc and TMJ injuries
that I see clinically occur during this phase.
Phase 3
During the third phase, your torso is now descending back down in your
seat and your head and neck are at their peak forward acceleration.
At the same time, your car is slowing down. If you released the
pressure on your brake pedal during the first phases of the collision,
it will likely be reapplied during this phase. Reapplication of the
brake causes your car to slow down even quicker and increases the
severity of the flexion injury of your neck. As you move forward in
your seat, any slack in your seat belt and shoulder harness is taken
up.
Phase 4
This is probably the most damaging phase of the whiplash phenomenon.
In this fourth phase, your torso is stopped by your seat belt and
shoulder restraint and your head is free to move forward unimpeded.
This results in a violent forward-bending motion of your neck,
straining the muscles and ligaments, tearing fibers in the spinal
discs, and forcing vertebrae out of their normal position. Your spinal
cord and nerve roots get stretched and irritated, and your brain can
strike the inside of your skull causing a mild to moderate brain
injury. If you are not properly restrained by your seat harness, you
may suffer a concussion, or more severe brain injury, from striking the
steering wheel or windshield.
Injuries Resulting from Whiplash Trauma
As we discussed briefly in the introduction, whiplash injuries can
manifest in a wide variety of ways, including neck pain, headaches,
fatigue, upper back and shoulder pain, cognitive changes and low back
pain. Due to the fact that numerous factors play into the overall
whiplash trauma, such as direction of impact, speed of the vehicles
involved, as well as sex, age and physical condition, it is impossible
to predict the pattern of symptoms that each individual will suffer.
Additionally, whiplash symptoms commonly have a delayed onset, often
taking weeks or months to present. There are, however, a number of
conditions that are very common among those who have suffered from
whiplash trauma.
Neck pain
It is the single most common complaint in whiplash trauma, being
reported by over 90% of patients. Often this pain radiates across the
shoulders, up into the head, and down between the shoulder blades.
Whiplash injuries tend to affect all of the tissues in the neck,
including the facet joints and discs between the vertebrae, as well as
all of the muscles, ligaments and nerves.
Facet joint pain is the most common cause of neck pain following a car
accident. Facet joint pain is usually felt on the back of the neck,
just to the right or left of center, and is usually tender to the
touch. Facet joint pain cannot be visualized on x-rays or MRIs. It
can only be diagnosed by physical palpation of the area.
Disc injury is also a common cause of neck pain; especially chronic
pain. The outer wall of the disc (called the anulus) is made up of
bundles of fibers that can be torn during a whiplash trauma. These
tears, then, can lead to disc degeneration or herniation, resulting in
irritation or compression of the nerves running through the area.
This compression or irritation commonly leads to radiating pain into
the arms, shoulders and upper back, and may result in muscle weakness.
Damage to the muscles and ligaments in the neck and upper back are the
major cause of the pain experienced in the first few weeks following a
whiplash injury, and is the main reason why you experience stiffness
and restricted range of motion. But as the muscles have a chance to
heal, they typically don’t cause as much actual pain as they contribute
to abnormal movement. Damage to the ligaments often results in
abnormal movement and instability.
Headaches
After neck pain, headaches are the most prevalent complaint among those
suffering from whiplash injury, affecting more than 80% of all
people. While some headaches are actually the result of direct brain
injury, most are related to injury of the muscles, ligaments and facet
joints of the cervical spine, which refer pain to the head. Because
of this, it is important to treat the supporting structures of your
neck in order to help alleviate your headaches.
TMJ problems
A less common, but very debilitating disorder that results from
whiplash is temporomandibular joint dysfunction (TMJ). TMJ usually
begins as pain, clicking and popping noises in the jaw during movement.
If not properly evaluated and treated, TMJ problems can continue to
worsen and lead to headaches, facial pain, ear pain and difficulty
eating. Many chiropractors are specially trained to treat TMJ
problems, or can refer you to a TMJ specialist.
Brain injury
Believe it or not, mild to moderate brain injury is common following a
whiplash injury, due to the forces on the brain during the four phases
mentioned earlier. The human brain is a very soft structure,
suspended in a watery fluid called cerebrospinal fluid. When the
brain is forced forward and backward in the skull, the brain bounces
off the inside of the skull, leading to bruising or bleeding in the
brain itself. In some cases, patients temporarily lose consciousness
and have symptoms of a mild concussion. More often, there is no loss
of consciousness, but patients complain of mild confusion or
disorientation just after the crash. The long-term consequences of a
mild brain injury can include mild confusion, difficulty concentrating,
sleep disturbances, irritability, forgetfulness, loss of sex drive,
depression and emotional instability. Although less common, the nerves
responsible for your sense of smell, taste and even your vision may
be affected as well, resulting in a muted sense of taste, changes in
your sensation of smell and visual disturbances.
Dizziness
Dizziness following a whiplash injury usually results from injury to
the facet joints of the cervical spine, although in some cases injury
to the brain or brain stem may be a factor as well. Typically, this
dizziness is very temporary improves significantly with chiropractic
treatment.
Low back pain
Although most people consider whiplash to be an injury of the neck, the
low back is also commonly injured as well. In fact, low back pain is
found in more than half of rear impact-collisions in which injury was
reported, and almost three-quarters of all side-impact crashes. This
is mostly due to the fact that the low back still experiences a
tremendous compression during the first two phases of a whiplash
injury, even though it does not have the degree of flexion-extension
injury experienced in the neck.
Recovery from Whiplash
With proper care, many mild whiplash injuries heal within six to nine
months. However, more than 20% of those who suffer from whiplash
injuries continue to suffer from pain, weakness or restricted movement
two years after their accident. Unfortunately, the vast majority of
these people will continue to suffer from some level of disability or
pain for many years after that, if not for the rest of their lives.
Whiplash is a unique condition that requires the expertise of a skilled
health professional specially trained to work with these types of
injuries. The most effective treatment for whiplash injuries is a
combination of chiropractic care, rehabilitation of the soft tissues
and taking care of yourself at home.
Chiropractic Care
Chiropractic care utilizes manual manipulation of the spine to restore
the normal movement and position of the spinal vertebrae. It is by
far the single-most effective treatment for minimizing the long-term
impact of whiplash injuries, especially when coupled with massage
therapy, trigger point therapy, exercise rehabilitation and other soft
tissue rehabilitation modalities.
Soft Tissue Rehabilitation
The term ‘soft tissue’ simply refers to anything that is not bone, such
as your muscles, ligaments, tendons, nervous system, spinal discs and
internal organs. During a whiplash injury, the tissues that are
affected most are the soft tissues, the muscles, ligaments and discs in
particular. In order to minimize permanent impairment and
disability, it is important to use therapies that stimulate the soft
tissues to heal correctly. These include massage therapy,
electro-stimulation, trigger point therapy, stretching and specific
strength and range of motion exercises.
Home Care
The most effective chiropractic care and soft tissue rehabilitation
will be limited in its benefit if what you do at home or at work
stresses or re-injures you on a daily basis. For this reason, it is
important that your plan of care extend into the hours and days between
your clinic visits to help speed your recovery. Some of the more
common home care therapies are the application of ice packs,
limitations on work or daily activities, specific stretches and
exercises, taking nutritional supplements and getting plenty of rest.
Medical Intervention
In some severe cases of whiplash, it may be necessary to have some
medical care as part of your overall treatment plan. The most common
medical treatments include the use of anti-inflammatory medications,
muscle relaxants, trigger point injections and, in some cases, epidural
spinal injections. These therapies should be used for short-term
relief of pain, if necessary, and not be the focus of treatment. After
all, a drug cannot restore normal joint movement and stimulate
healthy muscle repair. Fortunately, surgery is only needed in some
cases of herniated discs, when the disc is pressing on the spinal
cord, and in some cases of spine fractures.
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