title: [The development of degenerative disc animal model in rhesus monkey].
abstract: OBJECTIVE
  To develop the degenerative disc animal model with histological and MRI observation.
  
  
  METHODS
  Eight adult Rhesus monkeys were divided randomly into two groups after the lumbar discs MRI scan. The operated group, 6 monkeys, was subjected to annulus resection. A 5 mm x 3 mm cut was made in the left anterolateral part of the fibrosus annulus on L(4,5), L(5,6) and L(6,7) discs. The operated discs were scanned with MRI at 1 week, 4 weeks, 8 weeks, 13 weeks and 20 weeks postoperatively and observed histologically at 4 weeks, 8 weeks and 20 weeks after operation.
  
  
  RESULTS
  The histological structure of Rhesus monkey was similar to that of human being. The percentage of high signal intensity area in the operated discs reduced significantly at 8, 13, 20 weeks after operation (P < 0.05). The fibroplasia outside the annular tear could be observed in all 6 operated discs at 4 weeks postoperatively. Two of 6 operated discs underwent fibroplasia at 20 weeks after operation. No heal evidence in the inner tear was showed after operation.
  
  
  CONCLUSIONS
  The animal model for human lumbar disc degeneration could be obtained by anterio-lateral annulus resection. The early-stage degenerative evidence could be observed without injury by measuring the percentage of the high intensity area of the operated discs on T2WI of MRI.
authors.affiliation: Department of Orthopedic, Affiliated Hospital of Medical College, Qingdao University, Qingdao 266003, China.
authors.forename: C
authors.initials: C
authors.lastname: Guo
authors.forename: Y
authors.initials: Y
authors.lastname: Hu
authors.forename: X
authors.initials: X
authors.lastname: Wu
authors.forename: F
authors.initials: F
authors.lastname: An
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D007405:Intervertebral Disc Displacement / Q000473:pathology; D008159:Lumbar Vertebrae / Q000473:pathology / Q000601:surgery; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008297:Male; D011897:Random Allocation