Injury: Whiplash

Definition
Description
Demographics
Causes and Symptoms
Diagnosis
Treatment
Prognosis
Prevention
The Future
For more information

Definition

Whiplash is a general term for injuries to the neck caused by stretching of the spine and the soft tissues in the neck when the head is moved sharply forward and then snapped back. It is not a formal medical term; doctors are more likely to use phrases like “cervical sprain” to describe whiplash.

Description

Whiplash injuries most commonly occur when a person is in a car or amusement park ride and is struck from behind. The impact pushes the car forward, which in turn throws the occupant's head forward suddenly and then sharply backward, causing overstrain on the muscles or tearing of other soft tissues in the neck and shoulders. Some people feel pain at the time of the accident, while others may not feel the effect of the whiplash injury until several days later. Symptoms may range from soreness or stiffness in the neck and shoulders for a few days to severe pain and disability from injuries to the vertebrae in the neck.

Demographics

Whiplash injuries are quite common in the United States and Canada, particularly those related to auto accidents. The National Highway Traffic Safety Administration (NHTSA) estimates that there are between 750,000 and 900,000 whiplash injuries related to automobile travel each year in the United States; about 40 percent of these are caused by rear-impact collisions. They are among the most frequently reported injuries in insurance claims, amounting to about $8.5 billion in insurance pay-outs each year.

Females tend to be at greater risk of whiplash injury than males regardless of whether they are driving the car or riding as a passenger. Apart from gender, drivers are more likely to get a whiplash injury than a front-seat passenger, possibly because drivers are more likely to move forward to try to control the car when hit from behind whereas passengers are more likely to be leaning further back in their seats. Passengers in the rear seats of a car have a slightly lower risk of whiplash injury than drivers or front-seat passengers.

Causes and Symptoms

Although most whiplash injuries are caused by rear-end auto collisions, they can also be caused by:

• Amusement park rides, particularly roller coasters and bumper-car rides
• Falling from a horse, bicycle, or motorcycle
• Railroad and airplane accidents
• Contact injuries in sports like football, wrestling, or judo
• Being hit on the head by a falling object
• Being shaken or hit on the head by an abusive parent or other attacker

Doctors do not agree, however, on exactly what causes the pain of whiplash in terms of the structures of the human neck. Some think that whiplash injury is caused by hyperextension of the neck, which is the medical term for stretching the neck beyond its normal range of motion. Other doctors think that the biological cause of whiplash injuries is damage to nerve endings in the neck.

There is no clear relationship between an automobile's speed at the time of an accident and a passenger's risk of a whiplash injury; people have reported whiplash injuries when their car was traveling at no more than 15 miles per hour (24 kilometers per hour).

Some doctors use a four-level scale for assessing the symptoms of a whiplash injury. The scale was first drawn up by a task force in Quebec in 1995.

• Level 1: Soreness or stiffness in the neck but there are no physical signs that can be detected by a doctor.
• Level 2: The patient complains of pain and the doctor finds a decreased range of motion in the neck.
• Level 3: The person has pain moving from the neck into the shoulders and arms plus such symptoms as insomnia, weakness, headache, blurred vision, or ringing in the ears.
• Level 4: In addition to the patient's symptoms, the doctor can detect dislocations or fractures of the bones in the neck, or injury to the spinal cord.

Diagnosis

People with only mild whiplash injuries may simply treat themselves at home (see sidebar). While it is not always necessary to see a doctor for whiplash, people who notice tingling or numbness in their arms or legs, loss of function in their limbs, severe pain when trying to move the neck, pain moving from the neck into the shoulders, headache, or dizziness should see their doctor or go to a hospital emergency department as soon as possible.

Home Treatment for Whiplash

Home care for whiplash includes applying heat or cold to the neck and taking mild over-the-counter pain relievers. A common recommendation is to apply ice to the patient'sneckfor twenty minutes at a time each hour for the first twenty-four hours while the patient is awake. The ice should not be applied directly to the skin but placed inside an ice pack or wrapped in a towel. After the first day or two of recovery, the patient should use a heating pad or other method of applying heat to warm and loosen the neck muscles for stretching exercises.

Acetaminophen or ibuprofen are recommended instead of aspirin for pain relief and to bring down inflammation in the soft tissues of the neck. If the pain is severe, the doctor may prescribe a pain reliever containing codeine or a muscle relaxant. These medications should be taken at bedtime as they often cause drowsiness.

Doctors diagnose the seriousness of whiplash injuries by gently moving the patient's head to see how far the neck can move in different directions. They will also press on different parts of the neck to see whether there are any localized sore spots. X rays and other imaging

studies may be ordered to check for bone fractures or other signs of serious injury to soft tissues.

Treatment

Treatment for mild whiplash injuries may involve massage therapy and heat application in addition to treatment at home with bed rest, ice, and mild pain relievers. Within three to four days of the injury, the patient will be asked to start range-of-motion exercises to keep the neck flexible. These exercises usually involve gently rolling the head from side to side or bending the neck backward and forward. If the pain persists for several months, the doctor may recommend physical therapy to strengthen the neck muscles. The doctor may also inject a local anesthetic to reduce muscle spasms before the patient begins the range-of-motion exercises.

Cervical (neck) collars are not used as often now as they were some years ago. The reason for this change is that wearing a collar for several weeks or months causes the muscles in the neck to lose their strength. People who have trouble sleeping because of whiplash pain, however, may be given a cervical collar to wear while they are sleeping.

Some people are helped by alternative and complementary treatments for whiplash injuries. The approaches that have been found helpful include acupuncture, massage therapy, and chiropractic.

Prognosis

Most people feel better within a few days or weeks after a whiplash injury. Severe damage to the bones in the neck or to the spinal cord, however, can result in permanent disability and chronic pain. There is a 40 percent chance of having some symptoms as long as three months after a whiplash injury, and an 18 percent chance that the symptoms will last for as long as two years, but there is no reliable way to predict a specific individual's risk of falling into one of these two groups.

Prevention

Head restraints have been mandated in new passenger cars manufactured in the United States since 1969. The effectiveness of these restraints in preventing whiplash injuries is debated by specialists who study the effects of whiplash injuries on the human body, however. One problem is that people do not always adjust their head restraint to the proper height for the size of their head and neck. The head restraint should be

adjusted so that the middle of the headrest is even with the upper tips of the ears.

Another problem is that the stiffness of a car seat affects the likelihood of a whiplash injury as much as the quality of the head restraint and its proper adjustment. Safety engineers are still working on designing better head restraints, including some that adjust their position automatically when the driver moves the seat forward or backward.

The Future

Some causes of whiplash injury, such as abusive or criminal attacks or accidents involving public transportation, would be difficult to prevent entirely. The risk of sports injuries to the neck can be lowered somewhat by redesigning shoulder pads and other protective equipment and by teaching athletes to minimize their risk of neck injuries. Better automobile design might help also, but even the best-designed seat or head restraint will not be effective if drivers and passengers fail to wear seat belts and adjust their head restraints correctly.

SEE ALSO Shaken baby syndrome

WORDS TO KNOW

Acupuncture: A form of alternative medicine in which very fine needles are inserted into the skin at specific points on the body for pain relief.

Chiropractic: A form of alternative medicine that treats disorders of the joints and muscles by adjusting the patient's spine or other joints.

Hyperextension: Stretching or moving a part of the body beyond its normal range of motion.

For more information

BOOKS

Ferrari, Robert. The Whiplash Encyclopedia: The Facts and Myths of Whiplash, 2nd ed. Sudbury, MA: Jones and Bartlett Publishers, 2006.

WEB SITES

Insurance Institute for Highway Safety (IIHS). Q&As: Neck Injury. Available online at http://www.iihs.org/research/qanda/neck_injury.html#1(posted December 2007; accessed April 26, 2008).

Mayo Clinic. Whiplash. Available online at http://www.mayoclinic.com/health/whiplash/DS01037 (updated December 19, 2007; accessed April 25, 2008).

Nemours Foundation. Dealing with Sports Injuries. Available online at http://www.kidshealth.org/teen/exercise/safety/sports_injuries.html (updated June 2007; accessed April 27, 2008). Advice for teens on whiplash and other sports-related neck injuries.

SpineUniverse. Whiplash Animation. Available online at http://www.spineuniverse.com/videos/whiplash/ (accessed April 26, 2008). This is a two-minute animation with voiceover that describes the structure of the neck and spinal column as well as explaining what happens in whiplash injuries. The transcript of the voiceover is printed beneath the animation.