Fear avoidance and prognosis in back pain - A systematic review and synthesis of current evidence

Objective. Fear of pain, which is hypothesized to result in avoidance behavior, has been described as an obstacle to recovery in populations of patients with low back pain. However, the evidence to support the link between high levels of fear at early stages of pain and poor prognosis has yet to be systematically assessed. We undertook this review to explore current evidence and to propose further development of theoretical models. Methods. We performed a systematic literature review of all prospective inception cohorts of patients with acute low back pain that measured fear of pain (often described as fear avoidance) at baseline. Results. We reviewed 9 studies reported between 2001 and 2006. Several of these had acceptable/good methodology. Three studies, of which at least 1 had excellent methodology, showed no link between measures of fear at baseline and poor prognosis in the short term (3 months) or the long term (12 months). Three studies with acceptable methodology showed weak evidence for such a link, but the effect sizes were small. The only study with acceptable methodology to find a clear link suggested that fear of movement was linked to long-term pain. Conclusion. Despite the prevalent focus on fear of pain at early stages of back pain, there is little evidence to link such fear states with poor prognosis. There is some evidence to suggest that fear may play a role when pain has become persistent. There is a growing consensus that distress/depression plays an important role at early stages, and clinicians should focus on these factors.