title: Direction of the formation of anterior lumbar vertebral osteophytes.
abstract: BACKGROUND
  X-ray images of lumbar degenerative diseases often show not only claw osteophytes, but also pairs of osteophytes that form in a direction away from the adjacent disc. We have investigated the direction of the formation of anterior lumbar vertebral osteophytes across the lumbar vertebrae using a sufficient number of lumbar radiographs, because osteophytes images can provide essential information that will contribute to the understanding of the pathology and progress of lumbar spine degeneration.
  
  
  METHODS
  The direction of the formation of 14,250 pairs of anterior lumbar vertebral osteophytes across the adjacent intervertebral discs in 2,850 patients who were all over 60 years old was investigated. Anterior lumbar vertebral osteophytes were distributed into six groups based on the direction of extension of each pair of osteophytes across the intervertebral disc space.
  
  
  RESULTS
  In L1-L2 and L2-L3, the number of patients classified into groups B (the pair of osteophytes extended in the direction of the adjacent disc) and C (almost complete bone bridge formation by a pair of osteophytes across the intervertebral disc space) was larger than that classified into group D (the pair of osteophytes extended in a direction away from the adjacent disc). In L3-L4, L4-L5 and L5-S1, the number of patients in group D was greater than that of patients belonging to groups B and C.
  
  
  CONCLUSIONS
  Our study showed that pairs of osteophytes frequently formed in the direction of the adjacent disc in the upper lumbar vertebrae (L1-L2 and L2-L3) and in the direction away from the adjacent disc in middle or lower lumbar vertebrae (L3-L4, L4-L5, and L5-S1).
authors.affiliation: Department of Orthopaedic Surgery, Mie University Graduate School of Medicine, 2-174 Endobashi, Tsu city, Mie prefecture, 514-8507, Japan. ykasai@clin.medic.mie-u.ac.jp
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Kasai
authors.forename: Eiji
authors.initials: E
authors.lastname: Kawakita
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Sakakibara
authors.forename: Koji
authors.initials: K
authors.lastname: Akeda
authors.forename: Atsumasa
authors.initials: A
authors.lastname: Uchida
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D054850:Osteophyte / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology; D011859:Radiography / Q000379:methods; D016059:Range of Motion, Articular / Q000502:physiology; D013128:Spinal Osteophytosis / Q000000981:diagnostic imaging* / Q000473:pathology* / Q000503:physiopathology; D013130:Spinal Stenosis / Q000150:complications / Q000473:pathology / Q000503:physiopathology; D055009:Spondylosis / Q000150:complications / Q000473:pathology / Q000503:physiopathology