title: Modic changes of the lumbar spine: prevalence, risk factors, and association with disc degeneration and low back pain in a large-scale population-based cohort.
abstract: BACKGROUND
  Modic changes (MC) are bone marrow lesions on magnetic resonance imaging (MRI), suggestive of being associated with low back pain (LBP). Data on determinants of MC and their association with disc degeneration and other spinal phenotypes, as well as that of LBP, rely mostly on small-scale patient populations and remain controversial.
  
  
  OBJECTIVE
  This study addressed the potential determinants of MC and their association with disc degeneration and LBP among Southern Chinese.
  
  
  METHODS
  A cross-sectional, population-based study was carried out.
  
  
  METHODS
  This study consisted of 2,449 Southern Chinese volunteers.
  
  
  METHODS
  Sagittal T2-weighted MRIs of the lumbar spine were assessed for the presence of MC and other spinal phenotypes (eg, disc degeneration, disc displacement, Schmorl nodes) in all individuals. Subjects' demographics, occupation, lifestyle, and clinical profiles were assessed.
  
  
  RESULTS
  The overall prevalence of MC was 5.8% (n=141), which increased with advancing age. Modic changes predominantly occurred at the lowest two lumbar levels (83%). In the multivariate analyses, only the presence of disc displacement and a higher disc degeneration score were associated with MC at the upper lumbar levels (L1/L2-L3/L4) (p<.01). The presence of MC at the lowest two lumbar levels (L4/L5-L5/S1) were associated with age, the presence of Schmorl nodes, disc degeneration or displacement, and historical lumbar injury (p<.01). Subjects who were both smokers and overweight or obese had increased likelihood of MC in the lower spine (OR: 2.18; 95% CI: 1.10-4.30). The presence of MC at the lower lumbar levels were associated with historical LBP (OR: 1.93; 95% CI: 1.05-3.54) and with severity and duration of symptoms (p<.05).
  
  
  CONCLUSIONS
  Based on one of the largest MRI studies to assess lumbar MC, we noted that MC were associated with both disc degeneration and the presence and severity of LBP. Determinants and association of MC with disc degeneration and clinical symptoms in the upper versus the lower lumbar spine were different. Our study further stresses the significance of MC as important imaging phenotypes associated with LBP.
authors.affiliation: Department of Orthopaedics & Traumatology, The University of Hong Kong, Professorial Block, 5th Floor, 102 Pokfulam Road, Pokfulam, Hong Kong, SAR, China.
authors.forename: Florence P S
authors.initials: FP
authors.lastname: Mok
authors.affiliation: Department of Orthopaedics & Traumatology, The University of Hong Kong, Professorial Block, 5th Floor, 102 Pokfulam Road, Pokfulam, Hong Kong, SAR, China. Electronic address: dsamartzis@msn.com.
authors.forename: Dino
authors.initials: D
authors.lastname: Samartzis
authors.affiliation: Department of Physical and Rehabilitation Medicine, Medical Research Center Oulu, University of Oulu and Oulu University Hospital, Box 5000, 90014, Oulu, Finland; Finnish Institute of Occupational Health, Health and Work Ability, and Disability Prevention Centre, Aapistie 1, 90220, Oulu, Finland.
authors.forename: Jaro
authors.initials: J
authors.lastname: Karppinen
authors.affiliation: School of Nursing, The University of Hong Kong, William M.W. Mong Block, 4/F, 21 Sassoon Road, Pokfulam, Hong Kong, SAR, China.
authors.forename: Daniel Y T
authors.initials: DY
authors.lastname: Fong
authors.affiliation: Department of Orthopaedics & Traumatology, The University of Hong Kong, Professorial Block, 5th Floor, 102 Pokfulam Road, Pokfulam, Hong Kong, SAR, China.
authors.forename: Keith D K
authors.initials: KD
authors.lastname: Luk
authors.affiliation: Department of Orthopaedics & Traumatology, The University of Hong Kong, Professorial Block, 5th Floor, 102 Pokfulam Road, Pokfulam, Hong Kong, SAR, China. Electronic address: cheungmc@hku.hk.
authors.forename: Kenneth M C
authors.initials: KM
authors.lastname: Cheung
mesh_terms: D000328:Adult; D000368:Aged; D002681:China; D005260:Female; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000453:epidemiology*; D017116:Low Back Pain / Q000453:epidemiology*; D008161:Lumbosacral Region / Q000473:pathology*; D008297:Male; D008875:Middle Aged
keywords: Degeneration; Disc; End plate; Lumbar; MRI; Modic; Phenotype; Spine