Whiplash Injuries from Auto Accidents
Whiplash is a common term used to describe an acceleration-deceleration injury mechanism that affects the neck and cervical spine. In automobile accidents, it is usually the result of posterior or lateral impact, such as a rear-end automobile collision, but can also occur in other types of personal injury accidents like diving into water or even in slip and fall accidents. Whiplash can cause bone or soft tissue injuries, which in turn can produce different clinical manifestations generally called disorders associated with whiplash.
It is estimated that the whiplash syndrome occurs in 20 to 50% of the car accidents that occur in the USA. In some cases, the symptoms can be relatively mild and a patient may recover completely within 2-3 months. However, it is important to keep in mind that some patients develop chronic symptoms after these types of injuries.
The classic motor vehicle collision presentation of whiplash occurs via following sequence:
- a) The vehicle suffers an impact from behind and undergoes an acceleration forward. Approximately 100 milliseconds later the patient’s trunk and shoulders suffer a similar acceleration.
- b) The head remains static in space and undergoes a forced hyperextension movement. Hyperextension is the main and most potent cause of damage. During this movement, the cervical articular facets and their ligamentous capsules, the intervertebral discs, the nerves, and the muscle fibers (mainly of the scalenes and sternocleidomastoids) can be affected. The soft tissues of the neck can suffer microscopic hemorrhages and edema that instigate a locoregional inflammatory processes.
- c) After cervical hyperextension, the force of inertia moves the head forward, resulting in hyperflexion. The flexion of the cervical spine stops when the chin hits the chest, but not the hyperextension that has no anatomical limitation. During hyperflexion, the posterior cervical musculature, the posterior common vertebral ligament, and the occipital ligament complex are all affected.
Whiplash Auto Accident Symptoms
Pain in the neck region
The primary manifestation of whiplash syndrome following a car or truck accident is pain in the neck, which usually intensifies with sudden movements. It is usually associated with muscular contracture and limitation of mobility. The pain may radiate to the head, shoulders, or upper extremities.
Headaches are a very frequent symptom and are usually of suboccipital or occipital localization, extending to the temporal or orbital region. Some experts suggest that the headache occurs due to the cerebral contusion resulting from the whiplash. Like bruises in other tissues, cerebral contusion can be associated with multiple microhemorrhages, small blood vessel leaks into brain tissue.
Some patients present with issues involving balance, confusion, and vertigo. These symptoms are usually due to injury of the structures of the inner ear.
When muscle weakness occurs in association with sensory disorders and alterations of tendon reflexes, it is likely that there is also an injury to the spinal nerves. However, it is more frequent for patients to present with subjective feelings of weakness, heaviness or fatigue in the upper extremities that are not accompanied by neurological abnormalities.
Some patients have tingling and/or numbness in the upper extremities, especially in the fingers. It extremely important to rule out other neurological alterations that could indicate the existence of nerve compression.
A detailed clinical history and a thorough physical examination are the basis for a correct diagnosis. However, the for chronic symptoms in some patients usually leads to the performance of multiple complementary studies, including radiologic studies and or MRIs.
The relationship between a straightening of the cervical spine, i.e. a reversal of cervical lordosis, and the diagnosis or severity of whiplash syndrome has been ruled out, in fact, it is accepted that almost 40% of people without previous cervical trauma present this radiographic alteration.
In patients with whiplash syndrome, it has been shown that small lesions of the vertebra and intervertebral discs cannot be detected by routine examinations such as radiography. The utility of an X-ray examination for detecting whiplash and more minute injuries of the cervical spine is low compared with the detection of traumatic changes by magnetic resonance imaging (MRI). MRI is an excellent diagnostic method to identify the existence of injuries secondary to whiplash.
Nerve conduction and electromyography studies should also be considered as a complementary test in order to rule out neurological complications.
Most current studies related to the treatment of whiplash syndrome recommend immobilization with a soft collar during the first week, followed by early rehabilitation and physiotherapy of the affected area for at least 8 weeks. The use of analgesics combined with diathermy, a therapeutic method that uses high-frequency electric currents to raise the temperature in different anatomical areas, can help a more rapid resolution of the symptomatology. Other treatment modalities have included injections of sterile water into the trigger points, and transcutaneous electrostimulation.
The treatment of whiplash syndrome usually does not require surgery. However, this is a valid option in severe cases or in those patients in whom conservative treatment has failed.
The type of surgery required depends on the injured structures. Whiplash can cause herniation or rupture of intervertebral discs which can cause persistent pain and neurological disturbances if the disc, or a part of it, compresses the spinal cord or a nerve root. In these cases, the surgeon performs a discectomy, which consists of the surgical removal of the damaged disc. After the discectomy surgeons must stabilize the spine, this can be done by placing an artificial vertebral disc or by vertebral fusion, which is done by placing a bone graft and a biological substance that stimulates bone fusion between the vertebrae, in addition the surgeon places screws, plates and/or rods to increase the stability of the spine. In more severe cases, the whiplash mechanism can result in life threatening conditions such as a hangman’s fracture, which is an actual break in the second cervical vertebrae (C2).
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