title: MR imaging of the lumbar spine: prevalence of intervertebral disk extrusion and sequestration, nerve root compression, end plate abnormalities, and osteoarthritis of the facet joints in asymptomatic volunteers.
abstract: OBJECTIVE
  To identify the magnetic resonance (MR) abnormalities of the lumbar spine that have a low prevalence in asymptomatic patients and thus determine the findings that are predictive of low back pain in symptomatic patients.
  
  
  METHODS
  Sagittal T1-weighted and sagittal and axial T2-weighted MR images were obtained in 60 asymptomatic volunteers aged 20-50 years. The MR images were evaluated with regard to intervertebral disk abnormalities, end plate abnormalities, and osteoarthritis of the facet joints by two musculoskeletal radiologists independently.
  
  
  RESULTS
  Disk bulging or disk protrusion was found in 42 (14%) and 48 (16%) of the intervertebral spaces in 37 (62%) and 40 (67%) subjects, respectively. High-signal-intensity zones were found commonly (in 23 [7.7%] and 25 [8.3%] of the intervertebral spaces in 19 (32%) and 20 (33%) subjects, respectively). Disk extrusions were less common (in 11 [3.7%] and 11 [3.7%] of the intervertebral spaces in 11 (18%) and 11 (18%) subjects, respectively). There were no disk sequestrations. A nerve root compression in a single intervertebral space was diagnosed by one reader. End plate abnormalities were found in two (0.7%) and six (1.9%) of the intervertebral spaces in two (3%) and six (10%) subjects, respectively. No severe osteoarthritis was diagnosed by either reader.
  
  
  CONCLUSIONS
  In patients younger than 50 years, disk extrusion and sequestration, nerve root compression, end plate abnormalities, and osteoarthritis of the facet joints are rare and, therefore, may be predictive of low back pain in symptomatic patients.
authors.affiliation: Department of Diagnostic Radiology, Orthopedic University Clinic Balgrist, Zurich, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Weishaupt
authors.forename: M
authors.initials: M
authors.lastname: Zanetti
authors.forename: J
authors.initials: J
authors.lastname: Hodler
authors.forename: N
authors.initials: N
authors.lastname: Boos
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000453:epidemiology / Q000473:pathology*; D008159:Lumbar Vertebrae / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009408:Nerve Compression Syndromes / Q000453:epidemiology / Q000473:pathology*; D010003:Osteoarthritis / Q000453:epidemiology / Q000473:pathology*; D015995:Prevalence; D013122:Spinal Diseases / Q000453:epidemiology / Q000473:pathology*