A prospective study predicting the outcome of chronic low back pain and physical therapy: the role of fear-avoidance beliefs and extraspinal pain. / Estudo prospectivo de fatores prognósticos em lombalgia crônica tratados com fisioterapia: papel do medo-evitação e dor extraespinal.

OBJECTIVE: To identify the prognostic factors for conventional physical therapy in patients with chronic low back pain (CLBP). METHODS: Prospective observational study. PARTICIPANTS: One hundred thirteen patients with CLBP selected at the Spinal Disease Outpatient Clinic. MAIN OUTCOME MEASURES: Pain intensity was scored using the Numeric Rating Scale (NRS), and function was measured using the Roland-Morris Disability Questionnaire (RMDQ). RESULTS: The Fear-Avoidance Beliefs Questionnaire work subscale results (FABQ-work; odds ratio [OR]=0.27, 95% confidence interval [CI] 0.13 to 0.56, p<0.001) and extraspinal pain (OR=0.35, 95% CI 0.17 to 0.74, p=0.006) were independently associated with a decreased response to conventional physical therapy for CLBP. CONCLUSION: We identified high FABQ-work and extraspinal pain scores as key determinants of a worse response to physical therapy among CLBP patients, supporting the need for a special rehabilitation program for this subgroup.