Whiplash is an acceleration-deceleration mechanism of energy transfer to the neck. This energy transfer may cause bony or soft tissue injuries (whiplash injury) that can result in various clinical manifestations (whiplash-associated disorders). Whiplash injury generally occurs in motor vehicle crashes (rear-end or side impact), and symptoms can be present several years after the injury. Eck and associates recently reviewed this commonly misunderstood injury.

Whiplash injury can have a wide variety of clinical and psychosocial symptoms (see accompanying table). Objective findings often do not correlate with the symptoms, which may indicate more severe injury. The typical presentation is head, neck, and thoracic pain, and limited range of motion, along with other vague symptoms. Psychosocial problems may be, or become, predominant, especially if patients are treated as malingerers or hypochondriacs. Radiographs may show preexisting degenerative changes or a slight flattening of the lordotic curvature of the neck. Computed tomographic scanning and magnetic resonance imaging are not indicated unless a neurologic deficit is present or disc or spinal cord damage is suspected.

Few adequate clinical trials have studied the treatment of whiplash injury. Furthermore, the injury is difficult to treat because patient complaints are typically vague. Although the traditional treatment modality has been a soft cervical collar to provide rest and motion restriction for the neck, use of this collar has been shown to slow healing. In one study, patients who received active treatment (rotational exercises 10 times every hour as soon as possible within the first four days after the injury) experienced less pain and more cervical flexion than those who were given the standard treatment (a soft cervical collar and resting of the neck for two weeks after the injury). In another study, early treatment was shown to be more effective than delayed treatment. In yet another study, an evaluation of patients six months after whiplash injury showed that those who were given high-dose steroid therapy within eight hours of the injury had fewer disabling symptoms and fewer sick days than those who were not given steroids. A small study showed benefit for cervical radiofrequency neurotomy, which serves to denature the nerves involved in chronic pain subsequent to whiplash injury.

The authors noted that most patients with whiplash injury recover without treatment in six months, but that active treatment may speed recovery. They also noted that ignoring a patient's complaints may exacerbate psychosocial problems and delay relief of suffering.