All study patients will be assessed initially by a physician in the CNOSP outpatient clinic to confirm that they meet the inclusion/exclusion criteria of the study. Patients receiving the EBC intervention will then receive re-assurance, advice to avoid passive treatments, acetominophen (except where contraindicated) for a period of 2-4 weeks, a four week course of lumbar spine spinal manipulative therapy administered by a CNOSP Chiropractor and advice to return to work in some capacity within eight weeks following the start of treatment. Patients randomized to the UC treatment arm will undergo the treatment(s) recommended by their family physicians.