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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