Natural evolution of late whiplash syndrome outside the medicolegal context

Abstract

Background: In Lithuania, few car drivers and passengers are covered by insurance and there is little awareness among the general public about the potentially disabling consequences of a whiplash injury. We took this opportunity to study the natural course of head and neck symptoms after rear-end car collisions.

Methods: In a retrospective questionnaire-based cohort study, 202 individuals (157 men; 45 women) were identified from the records of the traffic police department in Kaunas, Lithuania. These individuals were interviewed 1-3 years after experiencing a rear-end car collision. Neck pain, headache, subjective cognitive dysfunction, psychological disorders, and low back pain in this group were compared with the same complaints in a sex-matched and age-matched control group of uninjured individuals selected randomly from the population register of the same geographic area.

Findings: Neck pain was reported by 71 (35% [95% CI 29-42]) accident victims and 67 (33% [27-40]) controls. Headache was reported by 107 (53% [46-60]) accident victims and 100 (50% [42-57]) controls. Chronic neck pain and chronic headache (more than 7 days per month) were also reported in similar proportions (17 [8.4%; 5-13] vs 14 [6.9%; 4-12] and 19 [9.4%; 6-15] vs 12 [5.9%; 3-10]) by the two groups. Of those who reported chronic neck pain or daily headache after the accident, substantial proportions had had similar symptoms before the accident (7/17 for chronic neck pain; 10/12 for daily headache). There was no significant difference found. No one in the study group had disabling or persistent symptoms as a result of the car accident. There was no relation between the impact severity and degree of pain. A family history of neck pain was the most important risk factor for current neck symptoms in logistic regression analyses.

Interpretation: Our results suggest that chronic symptoms were not usually caused by the car accident. Expectation of disability, a family history, and attribution of pre-existing symptoms to the trauma may be more important determinants for the evolution of the late whiplash syndrome.