title: Do Muscle Characteristics on Lumbar Spine Magnetic Resonance Imaging or Computed Tomography Predict Future Low Back Pain, Physical Function, or Performance? A Systematic Review.
abstract: OBJECTIVE
  To determine whether lumbar muscle characteristics on magnetic resonance imaging (MRI) or computed tomography (CT) can inform clinicians as to the course of future low back pain (LBP), functional limitations, or physical performance, in adults with or without LBP. TYPE: Systematic review.
  
  
  METHODS
  We searched PubMed, Embase, and CINAHL through October 2014 for articles published in English in which authors assessed lumbar muscle characteristics on conventional MRI/CT as predictors of future LBP, functional limitations, or physical performance in adults. Studies with only postsurgical subjects were excluded. Our search identified 3554 articles, of which 6 observational cohort studies were included in the final review.
  
  
  METHODS
  We used the Newcastle Ottawa Scale to evaluate potential bias. Data were extracted on study design, study population, sample size, participant characteristics, details of MRI/CT assessments, interventions, study outcomes, analysis methods, and study results. Because of heterogeneity between studies, we conducted a qualitative evidence synthesis.
  
  
  RESULTS
  Among high-quality studies, there was limited evidence that, for individuals with or without LBP, greater MRI-detected multifidus cross-sectional area at L5-S1 predicted greater LBP intensity at 1-year follow-up, lesser erector spinae fat infiltration (FI) at L5-S1 predicted greater LBP intensity at 15-year follow-up, and greater erector spinae side-to-side FI asymmetry at L3-L4 predicted lower LBP frequency at 15-year follow-up; however, there was also limited evidence that all other MRI-detected paraspinal muscle characteristics examined were not predictive of LBP incidence, prevalence, frequency, or intensity at follow-up durations ranging from 1 to 15 years. There was limited evidence that greater CT-detected trunk muscle FI predicted worse physical performance in older adults at 3-year follow-up, but that trunk muscle cross-sectional area did not.
  
  
  CONCLUSIONS
  Few lumbar muscle characteristics have limited evidence for an association with future LBP and physical performance outcomes, and the vast majority have limited evidence for having no association with such outcomes.
authors.affiliation: Seattle Epidemiologic Research and Information Center (ERIC) Division of Rehabilitation Care Services, VA Puget Sound Healthcare System, 1660 South Columbian Way, Seattle, WA 98108; and Department of Rehabilitation Medicine, University of Washington School of Medicine, Seattle, WA.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Suri
authors.affiliation: Department of Rehabilitation Medicine, University of Washington School of Medicine, Seattle, WA.
authors.forename: Adrielle L
authors.initials: AL
authors.lastname: Fry
authors.affiliation: Department of Rehabilitation Medicine, University of Washington School of Medicine, Seattle, WA; and Division of Rehabilitation Medicine, Weill Cornell Medical College, New York, NY.
authors.forename: Alfred C
authors.initials: AC
authors.lastname: Gellhorn
mesh_terms: D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis / Q000503:physiopathology / Q000534:rehabilitation; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D009068:Movement / Q000502:physiology*; D064170:Paraspinal Muscles / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D014057:Tomography, X-Ray Computed / Q000379:methods*