title: Correlation between lumbar dysfunction and fat infiltration in lumbar multifidus muscles in patients with low back pain.
abstract: Lumbar multifidus muscles (LMM) are important for spinal motion and stability. Low back pain (LBP) is often associated with fat infiltration in LMM. An increasing fat infiltration of LMM may lead to lumbar dysfunction. The purpose of this study was to investigate whether there is a correlation between the severity of lumbar dysfunction and the severity of fat infiltration of LMM.
  
  
  
  In a cross-sectional study, 42 patients with acute or chronic LBP were recruited. Their MRI findings were visually rated and graded using three criteria for fat accumulation in LMM: Grade 0 (0-10%), Grade 1 (10-50%) and Grade 2 (>50%). Lumbar sagittal range of motion, dynamic upright and seated posture control, sagittal movement control, body awareness and self-assessed functional disability were measured to determine the patients' low back dysfunction.
  
  
  
  The main result of this study was that increased severity of fat infiltration in the lumbar multifidus muscles correlated significantly with decreased range of motion of lumbar flexion (p = 0.032). No significant correlation was found between the severity of fat infiltration in LMM and impaired movement control, posture control, body awareness or self-assessed functional disability.
  
  
  
  This is the first study investigating the relationship between the severity of fat infiltration in LMM and the severity of lumbar dysfunction. The results of this study will contribute to the understanding of the mechanisms leading to fat infiltration of LMM and its relation to spinal function. Further studies should investigate whether specific treatment strategies are effective in reducing or preventing fat infiltration of LMM.
authors.affiliation: Physio Hildebrandt, Sickingerstrasse 4, 3014, Bern, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Hildebrandt
authors.affiliation: , Hauptstrasse 26, 3254, Messen, Switzerland.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Fankhauser
authors.affiliation: Institute of Physiotherapy, School of Health Professions, Zurich University of Applied Sciences, Technikumstrasse 71, 8401, Winterthur, Switzerland.
authors.forename: André
authors.initials: A
authors.lastname: Meichtry
authors.affiliation: Institute of Physiotherapy, School of Health Professions, Zurich University of Applied Sciences, Technikumstrasse 71, 8401, Winterthur, Switzerland. luom@zhaw.ch.
authors.forename: Hannu
authors.identifier: 0000-0002-8023-4805
authors.initials: H
authors.lastname: Luomajoki
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D000328:Adult; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D064170:Paraspinal Muscles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011187:Posture / Q000502:physiology
keywords: Fat infiltration; Flexibility; Low back pain; Multifidus muscle