Chronic low back pain in individuals with chronic neck pain of traumatic and non-traumatic origin: a population-based study.

Background: It is unclear whether the prevalence of chronic low back pain is higher in chronic whiplash patients than in the general population. In a population-based study, we evaluated the prevalence of chronic low back pain in individuals with chronic neck pain of traumatic and non-traumatic origin, with special emphasis on whiplash injury.
Subjects and Methods: Additional questions concerning the patient's experience of neck and low back pain were added to the questionnaire of the MONICA health survey. 4,415 subjects aged 25-64 years were randomly selected from a geographically well-defined area in northern Sweden.
Results: The prevalences of chronic low back pain and chronic neck pain were 16% and 17%, respectively. 51% of subjects had both back and neck pain. Of the patients with neck pain, one quarter had a history of neck injury, which was related to whiplash injury in almost one-half of the cases. The prevalence of chronic low back pain in individuals with chronic non-traumatic neck pain was 53%, and it was 48% in those with chronic neck pain and a history of neck trauma. There was no difference in the prevalence of chronic low back pain between whiplash injury and other types of neck trauma. Confounding factors such as sex, age, marital status, BMI, smoking status and level of education were not significantly different between traumatic and non-traumatic groups.
Interpretation: Independently of traumatic or non-traumatic origin of the symptoms, the prevalence of chronic low back pain is 3 times higher in individuals with chronic neck pain than in the general population. Causes other than a history of neck trauma, such as chronic muskuloskeletal pain syndromes, may be important in evaluation of these cases.