title: The biologic response to particles from a potential disc prosthesis material.
abstract: METHODS
  An in vivo study of material from a potential disc prosthesis.
  
  
  OBJECTIVE
  To examine the histopathologic effect of particulate debris on the dura and neural tissue in sheep.
  
  
  BACKGROUND
  Disc prostheses are emerging as alternatives to spinal fusion for the treatment of symptomatic degenerative lumbar disc disease. Preclinical biocompatibility trials must be conducted before any device is considered for general use.
  
  
  METHODS
  Artificially generated wear particles of a material known as Sinux (DePuy Spine, Raynham, MA) were implanted directly onto the lumbosacral dura and nerve roots of 18 sheep that were randomly allocated to 3 groups to survive between 1 and 6 months. Tissue sections from T12 to the sacrum were examined for histopathological evidence of inflammation and wound healing in response to the particles and for the effects on the neural elements.
  
  
  RESULTS
  There was no significant evidence of inflammation, macrophage accumulation, or other tissue response. Other observations included some minor tissue pigmentation due to microhemorrhage, occasional but minimal lymphocyte infiltration, and crystalline Sinux in the fibroadipose connective tissue external to the dura.
  
  
  CONCLUSIONS
  Artificially generated particles of Sinux placed directly onto the dura and nerve roots did not induce any significant biologic response in a sheep model.
authors.affiliation: The Adelaide Centre for Spinal Research, Institute of Medical and Veterinary Science, Discipline of Pathology, The University of Adelaide, Hanson Institute Centre for Neurological Diseases, Adelaide, SA, Australia.
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Shimamura
authors.forename: Christopher
authors.initials: C
authors.lastname: Holding
authors.forename: David R
authors.initials: DR
authors.lastname: Haynes
authors.forename: Barrie
authors.initials: B
authors.lastname: Vernon-Roberts
authors.forename: Peter C
authors.initials: PC
authors.lastname: Blumbergs
authors.forename: Robert D
authors.initials: RD
authors.lastname: Fraser
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Moore
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D004388:Dura Mater / Q000473:pathology*; D020724:Elastomers; D019544:Equipment Failure Analysis; D005549:Foreign-Body Reaction / Q000209:etiology* / Q000473:pathology; D020007:Implants, Experimental; D007249:Inflammation; D007403:Intervertebral Disc / Q000601:surgery; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D010316:Particle Size; D019919:Prosthesis Implantation; D011897:Random Allocation; D012756:Sheep; D013126:Spinal Nerve Roots / Q000473:pathology*; D014945:Wound Healing
chemical_list: D001672:Biocompatible Materials; D020724:Elastomers