title: The efficacies of 2 ceramic bone graft extenders for promoting spinal fusion in a rabbit bone paucity model.
abstract: METHODS
  Prospective, randomized, controlled animal study.
  
  
  OBJECTIVE
  To determine the efficacies of 2 ceramic composite bone graft extenders for promoting spinal fusion.
  
  
  BACKGROUND
  Although autogenous bone is still considered the "gold standard" graft material for fusion procedures, its use is associated with a number of limitations. Synthetic ceramic composites represent a class of osteoconductive materials that may be employed as supplements or even alternatives to autograft. In this study, we compared the fusion rates generated by 2 ceramic composite bone graft extenders (MasterGraft and Mozaik Strips) with that obtained with autograft in a rabbit bone paucity model.
  
  
  METHODS
  Thirty-two New Zealand white rabbits undergoing noninstrumented posterolateral lumbar fusion were randomized to 1 of the following 4 groups: 100% autograft, 50% autograft, 50% autograft with Mozaik Strip, and 50% autograft with MasterGraft Strip. The rabbits were followed postoperatively for 8 weeks at which time the spinal segments were explanted and assessed for the presence of a solid fusion.
  
  
  RESULTS
  The arthrodesis rates by manual palpation of the 100% and 50% autograft controls were 75% (6 of 8 animals) and 12.5% (1 of 8), respectively (P < 0.01). In the 50% autograft/Mozaik and 50% autograft/MasterGraft groups, 3/8 and 1/8 of the rabbits were determined to have fused successfully, respectively (P = 0.569). However, there were no significant differences between the fusion rate of the 50% autograft cohort and those exhibited by the Mozaik or MasterGraft animals (P = 0.569 and 1.00, respectively).
  
  
  CONCLUSIONS
  This study provides further evidence that the quantity of autograft may influence the process of spinal fusion such that the arthrodesis rate was significantly lower when less bone was implanted. Neither of the ceramic composite scaffolds seemed to enhance the fusion response compared to an equivalent amount of autograft alone, suggesting that these substances may need to be combined with other osteogenic materials to optimize bone production.
authors.affiliation: Yale University School of Medicine, Department of Orthopaedics and Rehabilitation, New Haven, CT 06520, USA.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Miller
authors.forename: Kolawole
authors.initials: K
authors.lastname: Jegede
authors.forename: David
authors.initials: D
authors.lastname: Essig
authors.forename: Hitesh
authors.initials: H
authors.lastname: Garg
authors.forename: Jesse E
authors.initials: JE
authors.lastname: Bible
authors.forename: Debdut
authors.initials: D
authors.lastname: Biswas
authors.forename: Peter G
authors.initials: PG
authors.lastname: Whang
authors.forename: Jonathan N
authors.initials: JN
authors.lastname: Grauer
mesh_terms: D000818:Animals; D016025:Bone Transplantation / Q000295:instrumentation* / Q000379:methods; D002516:Ceramics; D007085:Ilium / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000601:surgery*; D011817:Rabbits; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D054457:Tissue Scaffolds