title: The Otto Aufranc Award: Demineralized bone matrix around porous implants promotes rapid gap healing and bone ingrowth.
abstract: BACKGROUND
  Noncemented revision arthroplasty is often complicated by the presence of bone implant gaps that reduce initial stability and biologic fixation. Demineralized bone matrix has osteoinductive properties and therefore the potential to enhance gap healing and porous implant fixation.
  
  
  OBJECTIVE
  We determined at what times and to what extent demineralized bone matrix promotes gap healing and bone ingrowth around a porous implant.
  
  
  METHODS
  We inserted porous titanium implants into the proximal metaphyses of canine femora and humeri, with an initial 3-mm gap between host cancellous bone and implants. We left the gaps empty (control; n = 12) or filled them with either demineralized bone matrix (n = 6) or devitalized demineralized bone matrix (negative control; n = 6) and left them in situ for 4 or 12 weeks. We quantified volume healing of the gap with new bone using three-dimensional micro-CT scanning and quantified apposition and ingrowth using backscattered scanning electron microscopy.
  
  
  RESULTS
  The density of bone inside gaps filled with demineralized bone matrix reached 64% and 93% of surrounding bone density by 4 and 12 weeks, respectively. Compared with empty controls and negative controls at 4 and 12 weeks, gap healing using demineralized bone matrix was two to three times greater and bone ingrowth and apposition were up to 15 times greater.
  
  
  CONCLUSIONS
  Demineralized bone matrix promotes rapid bone ingrowth and gap healing around porous implants.
  
  
  CONCLUSIONS
  Demineralized bone matrix has potential for enhancing implant fixation in revision arthroplasty.
authors.affiliation: Division of Orthopaedic Surgery, Faculty of Medicine, McGill University, Montreal, QC, Canada.
authors.forename: Letitia
authors.initials: L
authors.lastname: Lim
authors.forename: J Dennis
authors.initials: JD
authors.lastname: Bobyn
authors.forename: Kristian M
authors.initials: KM
authors.lastname: Bobyn
authors.forename: Louis-Philippe
authors.initials: LP
authors.lastname: Lefebvre
authors.forename: Michael
authors.initials: M
authors.lastname: Tanzer
mesh_terms: D000818:Animals; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation*; D001363:Awards and Prizes; D018775:Bone Demineralization Technique; D015519:Bone Density; D001857:Bone Matrix / Q000637:transplantation*; D001861:Bone Regeneration; D018786:Bone Substitutes; D004285:Dogs; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery* / Q000648:ultrastructure; D006622:Hip Prosthesis; D006811:Humerus / Q000000981:diagnostic imaging / Q000601:surgery* / Q000648:ultrastructure; D008297:Male; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D016062:Porosity; D011474:Prosthesis Design; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*; D055114:X-Ray Microtomography
chemical_list: D018786:Bone Substitutes; D014025:Titanium