BACKGROUND: Longstanding musculoskeletal pain is common in the general population and associated with frequent use of health care. Plain radiography is a common diagnostic approach in these patients despite knowledge that the use in the investigation of musculoskeletal pain is associated with low diagnostic yield, substantial costs and high radiation exposure. The aim of this study was to assess the use of diagnostic imaging and the proportion of pathological findings with regard to duration and distribution of pain in a cohort from the general population.

METHODS: An eight-year longitudinal study based on questionnaires at three occasions and medical records on radiological examinations done in medical care. Thirty subjects were selected from an established population based cohort of 2425 subjects that in 1995 answered a postal survey on pain experience. At baseline there were ten subjects from each of three pain groups; No chronic pain, Chronic regional pain, and Chronic widespread pain (CWP). Those who presented with CWP at two or all three occasions were considered to have a longstanding or re-occurring CWP. In total the thirty subjects underwent 102 radiological examinations during the eight year follow up.

RESULTS: There was a non-significant (p = 0.10) finding indicating that subjects with chronic pain at baseline (regional or widespread) were examined three times more often than those with no chronic pain. When the indication for the examination was pain, there was a low proportion of positive findings in subjects with longstanding CWP, compared to all others (5.3% vs 28.9%; p = 0.045). On the other hand, in examinations on other indications than pain the proportion of positive findings was high in the CWP group (62.5% vs 14.8%; p = 0.001).

CONCLUSION: Radiological examinations had a low diagnostic yield in evaluation of pain in subjects with longstanding/reoccurring CWP. These subjects had on the other hand more often positive findings when examined on other indications than pain. This may indicate that subjects with longstanding/reoccurring CWP are more prone to other diseases. It is a challenge for caregivers, often primary care physicians, to use radiological examinations to the best for their patients.