title: A plasma-sprayed titanium proximal coating reduces the risk of periprosthetic femoral fracture in cementless hip arthroplasty.
abstract: BACKGROUND
  The design of femoral component used in total hip arthroplasty is known to influence the incidence of periprosthetic femoral fractures (PFFs) in cementless hip arthroplasty.
  
  
  OBJECTIVE
  This study was undertaken to determine if 2 potential changes to an existing ABG II-standard cementless implant - addition of a roughened titanium plasma-sprayed proximal coating (ABG II-plasma) and lack of medial scales (ABG II-NMS) could decrease the risk of PFF in the intraoperative and early postoperative periods.
  
  
  METHODS
  Six pairs of human cadaveric femurs were harvested and divided into 2 groups, each receiving either of the altered implants and ABG II-standard (control). Each implant was tested in a biomechanical setup in a single-legged stance orientation. Surface strains were measured in intact femurs, during implant insertion, cyclic loading of the bone with the implant, and loading to failure. Strains with the ABG II-standard and the altered implants were compared.
  
  
  RESULTS
  ABG II-plasma showed better load-bearing capacity, with an average 42% greater failure load than that of ABG II-standard. The cortical hoop, axial and mean strains ABG II-plasma were less than those of ABG II-standard, demonstrating decreased tensile behaviour and better load transfer to the proximal femur. The final residual hoop strains in ABG II-plasma were closer to those of intact bone as compared to the standard stem. No differences in strains were observed between the standard stem and ABG II-NMS.
  
  
  CONCLUSIONS
  The increased load-bearing capacity and decreased proximal surface strains on femurs implanted with ABG II-plasma stem should reduce the risks of intraoperative and early postoperative PFF.
authors.affiliation: Biomedical Engineering, AMME, University of Sydney, Sydney, NSW, Australia.
authors.forename: Brad
authors.initials: B
authors.lastname: Miles
authors.affiliation: Specialist Orthopedic Group, Sydney, NSW, Australia.
authors.forename: William L
authors.initials: WL
authors.lastname: Walter
authors.affiliation: Biomedical Engineering, AMME, University of Sydney, Sydney, NSW, Australia.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Kolos
authors.affiliation: Specialist Orthopedic Group, Sydney, NSW, Australia.
authors.forename: Tim
authors.initials: T
authors.lastname: Waters
authors.affiliation: The Australian School of Advanced Medicine, Macquarie University, Sydney, NSW, Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: Appleyard
authors.affiliation: Medical Device Research Australia, Sydney, NSW, Australia.|Murray Maxwell Biomechanics Laboratory, Kolling Institute, Sydney University, Sydney, NSW, Australia.
authors.forename: R Mark
authors.initials: RM
authors.lastname: Gillies
authors.affiliation: WorelyParsons Advanced Analysis, Sydney, NSW, Australia.
authors.forename: Shane
authors.initials: S
authors.lastname: Donohoo
authors.affiliation: Biomedical Engineering, AMME, University of Sydney, Sydney, NSW, Australia.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Ruys
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D002102:Cadaver; D002484:Cementation; D020099:Coated Materials, Biocompatible / Q000138:chemical synthesis; D019245:Compressive Strength; D055119:Elastic Modulus; D019544:Equipment Failure Analysis; D005260:Female; D005264:Femoral Fractures / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control*; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D057068:Periprosthetic Fractures / Q000209:etiology / Q000503:physiopathology* / Q000517:prevention & control*; D058626:Plasma Gases / Q000737:chemistry; D011474:Prosthesis Design; D018570:Risk Assessment; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D014025:Titanium / Q000737:chemistry*; D016896:Treatment Outcome
chemical_list: D020099:Coated Materials, Biocompatible; D058626:Plasma Gases; C009495:titanium dioxide; D014025:Titanium
keywords: Cementless implant; failure load; periprosthetic femoral fractures; strain; titanium plasma-sprayed coating