Insight into Pain Resulting from Motor Vehicle Accidents

New studies on pain occurring after motor vehicle accidents suggest that psychological traits may be a more powerful predictor of the extent of pain symptoms than collision-related factors and that fibromyalgia symptoms presenting after a collision commonly resolved within 6 months.

In the first study, researchers evaluated the impact of collision-related factors (ie, direction, speed limit, extent of vehicle damage) and psychological status before the accident (ie, anxiety, anger, depression) on the number of body regions with moderate or severe pain (RMSP) among 414 patients.¹

Moderate or severe pain was found in 87% of patients, mostly involving the neck (57%), head (46%), and upper back (38%). Both anger and depression symptoms were linked to higher RMSP, while none of the collision-related factors were linked to the number of pain symptoms. For example, mean scores on the Center for Epidemiologic Studies Depression Scale increased from 8.2 to 11.4 among those with 1 to 2 or ≥6 RMSP, respectively. State-Trait Personality Inventory scores increased from a mean of 16.5 to 18.7 among patients with 1 to 2 or ≥6 RMSP, respectively. The findings were reported by Andrey Bortsov, MD, PhD, assistant professor, Department of Anesthesiology, University of North Carolina at Chapel Hill in Chapel Hill, North Carolina, and colleagues.

In another study by this research team, pain in the neck region after a collision was strongly associated with depressive symptoms and reduced physical health and mental health. Abdominal pain was the second strongest factor linked to these three outcomes, and it was the pain area most strongly associated with post-traumatic stress disorder. The findings “highlight the important influence of pain in a number of body regions on pain interference and emotional and physical health outcomes,” the authors reported.²

Findings from a third study suggest that fibromyalgia presenting after whiplash injury is often transient and may be overdiagnosed using the American College of Rheumatology (ACR) criteria. Instead, use of an adjusted diagnostic model that discounts neck/shoulder tenderness may be more accurate, suggested James P. Robinson, MD, clinical associate professor of Rehabilitation, Department of Physical Medicine, University of Washington in Seattle, Washington, and colleagues.³

The study involved 326 people with whiplash-associated neck pain that lasted longer than 3 months and a matched cohort of fibromyalgia patients without whiplash. Subjects with whiplash showed a similar number of mean tender points in the neck/shoulder area (approximately 9) but significantly fewer tender points in distal areas of the body (7.3 vs 5.6; P<0.001). Fourteen percent of patients met the ACR criteria for fibromyalgia at baseline. However, only 8% met the adjusted criteria. Furthermore, of those people who met the ACR criteria at baseline, 63% no longer met the criteria at the end of a 6-week treatment period (approximately 6 months after the whiplash injury), suggesting that fibromyalgia symptoms emerging after whiplash may be transient.

References

1. Bortsov A, Lee Y, Soward A, Jones J, Peak D et al. Individual vulnerability factors, but not collision-related factors, are associated with extent of moderate or severe pain syndromes in the immediate aftermath of motor vehicle collision. Pain. 2011. doi:10.1016/j.jpain.2011.02.041.
2. Whittington K, Bortsov A, Soward A, Jones J, Peak D et al. A pain in the neck? Which regions of body pain are most associated with pain interference and other health outcomes 6 weeks after motor vehicle collision. Pain 2011. doi:10.1016/j.jpain.2011.02.043.
3. Robinson JP, Theodore BR, Wilson HD, Waldo PG, Turk DC. Determination of fibromyalgia syndrome after whiplash injuries: Methodologic issues [published online ahead of print March 17]. Pain. 2011;152(6):1311-1316. doi:10.1016/j.jpain.2011.02.029.