title: The relative contributions of the disc and zygapophyseal joint in chronic low back pain.
abstract: METHODS
  A prospective cross-sectional analytic approach was taken.
  
  
  OBJECTIVE
  This study sought to determine the relative contribution of the disc and the zygapophyseal joint as a pain source in patients with chronic low back pain.
  
  
  BACKGROUND
  Previous studies have employed either zygapophyseal joint blocks or discography, but in no studies have both procedures been performed.
  
  
  METHODS
  Ninety-two consecutive patients with chronic low back pain were studied using both discography and blocks of the zygapophyseal joints.
  
  
  RESULTS
  Thirty-six patients (39%) had at least one positive discogram as defined by exact pain reproduction, an abnormal image, and a negative control. Eight patients responded to both a screening zygapophyseal joint block using lignocaine and a confirmatory block using bupivacaine. Only three patients had both a positive discogram and a symptomatic zygapophyseal joint.
  
  
  CONCLUSIONS
  In patients with chronic low back pain, the combination of discogenic pain and zygapophyseal joint pain is uncommon.
authors.affiliation: Faculty of Medicine, University of Newcastle, Australia.
authors.forename: A C
authors.initials: AC
authors.lastname: Schwarzer
authors.forename: C N
authors.initials: CN
authors.lastname: Aprill
authors.forename: R
authors.initials: R
authors.lastname: Derby
authors.forename: J
authors.initials: J
authors.lastname: Fortin
authors.forename: G
authors.initials: G
authors.lastname: Kine
authors.forename: N
authors.initials: N
authors.lastname: Bogduk
mesh_terms: D000328:Adult; D002045:Bupivacaine; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging; D007405:Intervertebral Disc Displacement / Q000150:complications* / Q000175:diagnosis; D008012:Lidocaine; D017116:Low Back Pain / Q000209:etiology*; D008159:Lumbar Vertebrae; D008297:Male; D011859:Radiography; D013122:Spinal Diseases / Q000150:complications / Q000175:diagnosis
chemical_list: D008012:Lidocaine; D002045:Bupivacaine