title: Preclinical trial of a novel surface architecture for improved primary fixation of cementless orthopaedic implants.
abstract: BACKGROUND
  A new surface architecture for cementless orthopaedic implants (OsteoAnchor), which incorporates a multitude of tiny anchor features for enhancing primary fixation, was tested in an ovine hemi-arthroplasty pilot study.
  
  
  METHODS
  Test animals were implanted with a hip stem component incorporating the OsteoAnchor surface architecture produced using additive layer manufacturing and control animals were implanted with stems containing a standard plasma sprayed titanium coating.
  
  
  RESULTS
  Intra-operative surgeon feedback indicated that superior primary fixation was achieved for the OsteoAnchor stems and rapid return to normal gait and load bearing was observed post-operation. Following a 16-week recovery time, histological evaluation of the excised femurs revealed in-growth of healthy bone into the porous structure of the OsteoAnchor stems. Bone in-growth was not achieved for the plasma sprayed stems.
  
  
  CONCLUSIONS
  These results indicate the potential for the OsteoAnchor surface architecture to enhance both the initial stability and long term lifetime of cementless orthopaedic implants.
authors.affiliation: Biomechanics Research Centre (BMEC), Biomedical Engineering, College of Engineering, National University of Ireland, Galway, Ireland.
authors.forename: Noel
authors.initials: N
authors.lastname: Harrison
authors.affiliation: Centre for Orthopaedic and Trauma Research (COTR), University of Adelaide, South Australia, Australia.
authors.forename: John R
authors.initials: JR
authors.lastname: Field
authors.affiliation: Skin and ECM Research Group, Anatomy, National University of Ireland, Galway, Ireland.
authors.forename: Fabio
authors.initials: F
authors.lastname: Quondamatteo
authors.affiliation: University College Hospital, Galway, Ireland.
authors.forename: William
authors.initials: W
authors.lastname: Curtin
authors.affiliation: Biomechanics Research Centre (BMEC), Biomedical Engineering, College of Engineering, National University of Ireland, Galway, Ireland.
authors.forename: Peter E
authors.initials: PE
authors.lastname: McHugh
authors.affiliation: Biomechanics Research Centre (BMEC), Biomedical Engineering, College of Engineering, National University of Ireland, Galway, Ireland. Electronic address: pat.mcdonnell@nuigalway.ie.
authors.forename: Pat
authors.initials: P
authors.lastname: Mc Donnell
mesh_terms: D000818:Animals; D018786:Bone Substitutes; D001842:Bone and Bones / Q000473:pathology; D005269:Femur / Q000473:pathology; D062785:Hemiarthroplasty / Q000295:instrumentation* / Q000379:methods*; D006622:Hip Prosthesis; D008297:Male; D009983:Orthopedic Equipment; D010865:Pilot Projects; D019736:Prostheses and Implants; D012107:Research Design; D012756:Sheep; D013499:Surface Properties; D014025:Titanium; D016474:Weight-Bearing
chemical_list: D018786:Bone Substitutes; D014025:Titanium
keywords: Bone in-growth; DMLS; Histology; Porous; Stem; Titanium