Whiplash is a common cause of neck pain and headaches which happens when the head and neck move backward or forward very quickly and forcefully.
Whiplash affects tissues in the front of neck such as the longus colli, scalene muscles, and the anterior longitudinal ligament. Larger muscles like the sternocleidomastoid can also be affected when the neck moves backward quickly. Large muscles in the back of the neck, like the splenius and trapezius, and smaller muscles like the rectus capitis posterior and scalenes, may also be affected during whiplash. A car accident or sports injury are common reasons for the head to move this way.
If the muscles stay sore and tight following a whiplash-type injury, headaches and neck pain can result. Physical therapy can help you decrease neck pain and headaches, help you improve your posture, and teach you to care for your neck using stretches and strengthening.
What causes whiplash?
Whiplash is most commonly caused by a motor vehicle accident in which the person is in a car that is not moving, and is struck by another vehicle from behind. It is commonly thought the rear impact causes the head and neck to be forced into hyperextended (backward) position as the seat pushes the person's torso forward - and the unrestrained head and neck fall backwards. After a short delay the head and neck then recover and are thrown into a hyperflexed (forward) position.
More recent studies investigating high-speed cameras and sophisticated crash dummies have determined that after the rear impact the lower cervical vertebrae (lower bones in the neck) are forced into a position of hyperextension while the upper cervical vertebrae (upper bones in the neck) are in a hyperflexed position. This leads to an abnormal S-shape in the cervical spine after the rear impact that is different from the normal motion. It is thought that this abnormal motion causes damage to the soft tissues that hold the cervical vertebrae together (ligaments, facet capsules, muscles).
How is whiplash diagnosed?
After an accident the patient may be taken to the hospital or a doctor's office to be examined. The doctor will examine the patient to determine if they have any injuries that require treatment. Based on the symptoms and examination findings the doctor may place a collar on the neck for additional support. The doctor may also obtain x-rays of the neck to check for more serious injury. The most important first step is to make sure there is no major injury to the neck, head or the rest of the body requiring immediate treatment.
If the x-rays are normal but the patient continues to have neck pain, the doctor may keep the cervical collar in place and see the patient back in the office in about a week for an additional examination. At that time the doctor may obtain new x-rays to see if there have been any changes. If the doctor is still concerned about soft tissue injuries, he or she may obtain either x-rays with the head leaning forward and backwards (dynamic x-rays) or obtain an MRI (magnetic resonance imaging study). These dynamic x-rays or MRI scans are better able to detect injuries to the soft tissues of the neck, especially instability, that may not been seen with normal x-rays of the neck.
What is the treatment for whiplash?
Treatment of whiplash depends on the wide variety of symptoms present.
The most important issue in the management of whiplash is optimal education of the patient about their injury. This includes information on the cause, potential treatments, and likely outcomes. Patients should understand that this is a real injury, but that nearly all patients have the ability to fully recover.
Prolonged immobilization actually slows the healing process. If there is no evidence of abnormal spinal alignment, early range of motion is advised.
Patients involved in early range of motion exercises have been shown to have a more reliable and rapid improvement in their symptoms. This treatment typically involves rotational exercises performed 10 times per hour as soon as symptoms allow within the first four days of the accident.
It seems that excessive rest and immobilization have been shown to have greater chances of chronic symptoms. This is explained by loss of range of motion leading to increased pain and stiffness. Immobilization also causes muscle atrophy (muscle wasting), decreased blood flow to the injured soft tissues, and healing of damaged muscles in shortened position that renders them less flexible.
Physical therapy can be useful in helping to wean a patient from a cervical collar as well as to help strengthen muscles and reduce painful motions. Occupational therapy can be used to help return the patient to the work environment.
What can be done to prevent whiplash?
While it is not always possible to prevent accidents, advances in automobile safety have attempted to reduce the associated risks. Many advances in seat belts and head restraints have been able to reduce the risk of whiplash injury. The proper use of these devices is crucial to their success in preventing injury. Head restraints are designed to prevent the head from moving into hyperextension when struck from behind. In order for this to work properly, the head restraint should be optimally positioned directly behind the head. If the head restraint is lowered below the level of the head it could actually force the head into further hyperextension after an impact. Many automobiles have additional safety equipment including air bags and air curtains to further protect drivers and passengers from injury.