Limited utility of imaging - Earlier use of imaging for low back pain without associated symptoms is not associated with improved outcomes but increases the use of invasive procedures. A 2009 systematic review and meta-analysis of six trials that compared immediate imaging (magnetic resonance imaging [MRI], computed tomography [CT], or radiography) with usual care for patients with acute and subacute low back pain, without signs or symptoms of infection or malignancy, found no significant differences in short-term (up to three months) or long-term (6 to 12 months)outcomes for measures of patient pain or function [47]. A subsequent prospective observational study in patients 265 years with back pain but without radiculopathy found no differences in disability at one year for patients who received early imaging (within six weeks of the inidex visit) compared with those who did not [48].