title: Correlation between the MRI changes in the lumbar multifidus muscles and leg pain.
abstract: OBJECTIVE
  In the assessment of the lumbar spine by magnetic resonance imaging (MRI), changes in the paraspinal muscles are frequently overlooked. In this study, our objective was to investigate the relationships between lumbar multifidus (MF) muscle atrophy and low back pain (LBP), leg pain and intevertebral disc degeneration.
  
  
  METHODS
  A retrospective study of 78 patients (aged 17-72) with LBP presenting with back pain with or without associated leg pain was undertaken. Their MR images were visually analysed for signs of lumbar MF muscle atrophy, disc degeneration and nerve root compression. The clinical history in each case was obtained from their case notes and pain drawing charts.
  
  
  RESULTS
  MF muscle atrophy was present in 80% of the patients with LBP. The correlation between MF muscle atrophy and leg pain was found to be significant (P < 0.01). However, the relationships between muscle atrophy and radiculopathy symptoms, nerve root compression, herniated nucleus pulposus and number of degenerated discs were statistically not significant.
  
  
  CONCLUSIONS
  Examination of the paraspinal muscles looking for atrophy of MF muscle should be considered when assessing MR images of lumbar spine. This may explain the referred leg pain in the absence of other MR abnormalities.
authors.affiliation: Department of Radiology, Woodend Hospital, Eday Road, Aberdeen, AB15 6XS, U.K.
authors.forename: D F
authors.initials: DF
authors.lastname: Kader
authors.forename: D
authors.initials: D
authors.lastname: Wardlaw
authors.forename: F W
authors.initials: FW
authors.lastname: Smith
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000473:pathology; D007866:Leg; D017116:Low Back Pain / Q000150:complications; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000473:pathology*; D009134:Muscular Atrophy, Spinal / Q000150:complications* / Q000175:diagnosis; D010146:Pain / Q000209:etiology*; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000150:complications