title: Lumbar Facet Tropism: A Comprehensive Review.
abstract: BACKGROUND
  Scattered reports exist in the medical literature regarding facet tropism. However, this finding has had mixed conclusions regarding its origin and impact on the normal spine.
  
  
  METHODS
  We performed a literature review of the anatomy, embryology, biomechanics, and pathology related to lumbar facet tropism.
  
  
  RESULTS
  Facet tropism is most commonly found at L4-L5 vertebral segments and there is some evidence that this condition may lead to facet degenerative spondylolisthesis, intervertebral disc disease, and other degenerative conditions.
  
  
  CONCLUSIONS
  Long-term analyses of patients are necessary to elucidate relationships between associated findings and facet tropism. In addition, a universally agreed definition that is more precise should be developed for future investigative studies.
authors.affiliation: Swedish Neuroscience Institute, Seattle, Washington, USA. Electronic address: fea4@case.edu.
authors.forename: Fernando
authors.initials: F
authors.lastname: Alonso
authors.affiliation: Swedish Neuroscience Institute, Seattle, Washington, USA.
authors.forename: Christina M
authors.initials: CM
authors.lastname: Kirkpatrick
authors.affiliation: University of Cincinnati-Mayfield Clinic, Cincinnati, Ohio, USA.
authors.forename: William
authors.initials: W
authors.lastname: Jeong
authors.affiliation: Swedish Neuroscience Institute, Seattle, Washington, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Fisahn
authors.affiliation: Department of Anatomical Sciences, St. George's University, Grenada, West Indies.
authors.forename: Sameera
authors.initials: S
authors.lastname: Usman
authors.affiliation: Swedish Neuroscience Institute, Seattle, Washington, USA; Department of Spine Surgery, Indian Spinal Injuries Centre, New Delhi, India.
authors.forename: Tarush
authors.initials: T
authors.lastname: Rustagi
authors.affiliation: Department of Anatomical Sciences, St. George's University, Grenada, West Indies.
authors.forename: Marios
authors.initials: M
authors.lastname: Loukas
authors.affiliation: Swedish Neuroscience Institute, Seattle, Washington, USA.
authors.forename: Jens R
authors.initials: JR
authors.lastname: Chapman
authors.affiliation: Swedish Neuroscience Institute, Seattle, Washington, USA.
authors.forename: Rod J
authors.initials: RJ
authors.lastname: Oskouian
authors.affiliation: Seattle Science Foundation, Seattle, Washington, USA.
authors.forename: R Shane
authors.initials: RS
authors.lastname: Tubbs
mesh_terms: D006801:Humans; D008137:Longitudinal Studies; D008159:Lumbar Vertebrae / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000473:pathology*; D008161:Lumbosacral Region / Q000002:abnormalities / Q000000981:diagnostic imaging / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D013168:Spondylolisthesis / Q000000981:diagnostic imaging / Q000473:pathology; D018523:Tropism; D021801:Zygapophyseal Joint / Q000002:abnormalities* / Q000473:pathology*
keywords: Anatomy; Facet; Spine; Tropism; Variation; Vertebral column