title: [Establishment of a rabbit model of lumbar intervertebral disc degeneration via the paraspinal approach].
abstract: OBJECTIVE
  To establish a rabbit model of intervertebral disc degeneration by puncturing the anulus fibrosus through an approach between the longissimus dorsi muscle and obliquus externus abdominis.
  
  
  METHODS
  The L(4/5) and L(5/6) intervetebral discs of 6 New Zealand white rabbits were punctured by an 18-gauge pin in the anterolateral annular fibrosus through an approach between the longissimus dorsi muscle and the obliquus externus abdominis with the right transverse processes of L(5) and L(6) resected; the L(2/3) discs were used as the control without exposure or needle stab, and the L(3/4) discs were subjected to sham operation with the discs exposed but not punctured after resecting the right transverse process of L(4). X-ray and magnetic resonance imaging (MRI) were performed preoperatively and at the 4th week after puncture. At 4 weeks after the operation, histological and immunohistochemical analyses of the discs were carried out.
  
  
  RESULTS
  X-ray of the punctured discs at 4 weeks after the operation presented a significant decrease of disc height, osteophytosis formation, and end-plate stiffness; an obvious decrease of signal intensity on T(2)-weighted images was found in the puncture group but not in the control or sham-operated groups. Gross morphological inspection showed atrophy of the nucleus pulposus, which became loose, soft, and fragile with a light yellow color. Histological and immunohistochemical analyses showed a significant decrease of notochordal cells and type II collagen in the nucleus pulposus in the puncture group as compared to the control and sham-operated groups.
  
  
  CONCLUSIONS
  Puncture through the approach between the longissimus dorsi muscle and the obliquus externus abdominis allows the establishment of a reliable animal model for studying intervertebral disc degeneration.
authors.affiliation: Image Center, Third Affiliated Hospital, Southern Medical University, Guangzhou 510630, China.
authors.forename: Yun-Neng
authors.initials: YN
authors.lastname: Cui
authors.forename: Rong-Ping
authors.initials: RP
authors.lastname: Zhou
authors.forename: Qi-Guang
authors.initials: QG
authors.lastname: Mai
authors.forename: Ming
authors.initials: M
authors.lastname: Lu
authors.forename: Song
authors.initials: S
authors.lastname: Xu
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.forename: Shao-Lin
authors.initials: SL
authors.lastname: Li
authors.forename: Da-di
authors.initials: DD
authors.lastname: Jin
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D055959:Intervertebral Disc Degeneration; D008159:Lumbar Vertebrae / Q000503:physiopathology*; D008297:Male; D011817:Rabbits