title: Effect of VEGF-A165 addition on the integration of a cortical allograft in a tibial segmental defect in rabbits.
abstract: OBJECTIVE
  Long-bone segmental defects caused by infection, fracture, or tumour are a challenge for orthopaedic surgeons. Structural allografts are sometimes used in their treatment but their poor biological characteristics are a liability. The objective of this study was to determine whether the addition of recombinant vascular endothelial growth factor-A (VEGF) to a structural allograft improved its integration into a rabbit tibial segmental defect in a non-union model.
  
  
  METHODS
  Tibial segmental defects were filled with heat sterilized allogenic tubular tibiae sections and then stabilized with a screw plate. In the VEGF treatment group (n = 6 tibiae), 2 μg of VEGF added to a 50 μl matrigel solution was inserted into the allograft cavity. In the control group (n = 6 tibiae), only matrigel was added. After 12 weeks, macroscopic and microscopic analysis, radiographs, and computerized micro-tomography (micro-CT) were performed. If allograft consolidation was present, a torsional resistance analysis was performed.
  
  
  RESULTS
  Addition of VEGF to the allograft decreased the rate of osteosynthesis failure compared with the control group (1/6 vs. 5/6, p = 0.08), increased trabecular continuity evaluated by micro-CT in the bone-allograft interphases (8/12 vs. 2/12, p = 0.036) and histological trabecular continuity (7/12 vs. 0/12, p = 0.0046). Full consolidation was observed in three tibiae of the VEGF group and one in the control group (differences not significant); however, torsional resistance showed no significant differences (n.s.).
  
  
  CONCLUSIONS
  Addition of VEGF to a structural allograph inserted into a rabbit tibial segmental defect increased allograft integration rate. Further research in this direction might help clinicians in dealing with large bone defects.
authors.affiliation: Department of Orthopaedic Surgery and Trauma, Hospital Universitario Ramón y Cajal, Cta Colmenar Km 9.100, 28034, Madrid, Spain. drmri@hotmail.com.
authors.forename: Miguel Angel
authors.initials: MA
authors.lastname: Ruiz-Ibán
authors.affiliation: Department of Orthopaedic Surgery and Trauma, Hospital Universitario Ramón y Cajal, Cta Colmenar Km 9.100, 28034, Madrid, Spain.
authors.forename: Fausto
authors.initials: F
authors.lastname: Gonzalez-Lizán
authors.affiliation: Department of Orthopaedic Surgery and Trauma, Hospital Universitario Ramón y Cajal, Cta Colmenar Km 9.100, 28034, Madrid, Spain.
authors.forename: Jorge
authors.initials: J
authors.lastname: Diaz-Heredia
authors.affiliation: Department of Anesthesiology and Reanimation, Hospital Universitario Ramón y Cajal, Cta Colmenar Km 9.100, 28034, Madrid, Spain.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Elías-Martin
authors.affiliation: Experimental Surgery Unit, Hospital Universitario Ramón y Cajal, Cta Colmenar Km 9.100, 28034, Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Correa Gorospe
mesh_terms: D064591:Allografts; D000818:Animals; D001860:Bone Plates; D001863:Bone Screws; D016025:Bone Transplantation; D004195:Disease Models, Animal; D005260:Female; D005593:Fracture Fixation, Internal / Q000379:methods*; D017102:Fracture Healing; D005599:Fractures, Ununited / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D016348:Osseointegration / Q000187:drug effects*; D011817:Rabbits; D011859:Radiography; D013978:Tibial Fractures / Q000000981:diagnostic imaging / Q000473:pathology / Q000628:therapy*; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology*
chemical_list: C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A