A number of studies have been published that help us understand which patients may be at a greater risk of long-term problems from whiplash injuries. The following is a summary of these new findings.
Some patients experience a car crash and suffer minor and localized symptoms; a substantial minority of patients, however, experience symptoms that don't resolve, and may even spread to other parts of the body. This generalized pain pattern has been recognized as a risk factor by numerous studies, and a current study looked specifically at this issue.
In this study by Peolsson et al.1, the authors examined 275 whiplash patients with chronic pain. They gave each patient a battery of pain, psychological, and disability surveys and recorded the number of painful regions that each patient reported.
“According to the present cross-sectional study, widespread pain in chronic WAD is associated with negative consequences with respect to pain intensity, prevalence of other symptoms (including depressive symptoms), some aspects of coping, life satisfaction/quality and general health. Our results indicate that, in different ways, the subgroup with widespread pain had a more fragile life situation than those with more local or regional WAD. Based on our results, we argue that a preventive perspective might be urgent and that clinical rehabilitation requires a broad assessment of the spread of pain, cognitive, and neuropsychological symptoms, and depressivity and catastrophizing thoughts or strategies.”
Central Nervous System Hypersensitivity
CNS hypersensitivity is related to generalized pain, but this recent report by Jull et al.2 examined the patients much more thoroughly, and specifically studied those patients with elevated pressure pain threshold or cold hyperalgesia tests. These two tests are useful in detecting an underlying central nervous system “overstimulation” that can occur in some whiplash patients.
In this study, 71 patients with whiplash were given two different treatments; one group was treated with physiotherapy and the other was given a self-management program.
The authors found that the physiotherapy group had more improvement, but “that relief was marginal in the subgroup with both widespread mechanical and cold hyperalgesia.” This study reinforces the idea that those with wider CNS responses to injury are more resistant to effective treatment.
Occupation and Arm and Shoulder Symptoms
Another new study3 looked at what factors influenced recovery in patients who were involved in litigation after their injury. 134 patients were interviewed an average of 11 months after their injury. The authors found the following:
Body Mass Index Not Related to Recovery
This Canadian study4 looked at the medical records 4,395 whiplash patients between 1994 and 1995; 87.7% of these individuals had recovered by November 1997.
“In the current study, body mass index was not associated with delayed recovery from whiplash injury. Compared with individuals who were normal weight, participants who were underweight, overweight, or obese had similar rates of recovery. The results challenge the view that being overweight or obese is a risk factor for chronic pain and disability following whiplash injuries.”
Peolsson M, Borsbo B, Gerle B. Generalized pain is associated with more negative consequences than local or regional pain: a study of chronic whiplash-associated disorder. Journal of Rehabilitation Medicine 2007;39:260-268.