title: The influence of cementing technique in hip resurfacing arthroplasty on the initial stability of the femoral component.
abstract: OBJECTIVE
  In clinical and retrieval analyses, over-penetration of cement, incomplete seating of the prosthesis with a resultant polar cement mass, or both, have been associated with early femoral failures of resurfacing arthroplasties. We used human bone specimens to experimentally compare the initial stability of different cementing techniques.
  
  
  METHODS
  Twenty-six pairs of fresh frozen femora were prepared for resurfacing using original instruments (DePuy ASR). ASR femoral resurfacing prostheses were implanted using two different cementing techniques: (1) component filling and (2) cement applicator. Real-time measurements of pressure and temperature during implantation, analyses of cement penetration and micro motions under torque application were performed.
  
  
  RESULTS
  Applicator use reduced significantly the cement penetration depth (9.2 mm vs 5.3 mm with the applicator, p = 0.001), polar mantle (8.1 mm vs 2.6 mm, p = 0.008), cement defects (3.7 mm vs 0.1 mm, p = 0.008) and interface temperatures (40.3°C vs 33.1°C, p < 0.001 ). Initial rotational stability showed statistically significant less extreme values with the cement applicator technique (range 3.4-51.7 m°/Nm, 11.0-29.7 m°/Nm, p = 0.024).
  
  
  CONCLUSIONS
  The cement applicator technique significantly reduces cement defects, incomplete seating, over-penetration and interface temperatures with a more consistent initial stability of the ASR femoral resurfacing prostheses.
authors.affiliation: Stiftung Orthopädische Universitätsklinik, Heidelberg, Germany. Rudi_Georg.Bitsch@urz.uni-heidelberg.de
authors.forename: Rudi G
authors.initials: RG
authors.lastname: Bitsch
authors.forename: Sebastian
authors.initials: S
authors.lastname: Jäger
authors.forename: Marcus
authors.initials: M
authors.lastname: Lürssen
authors.forename: Travis
authors.initials: T
authors.lastname: Loidolt
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Schmalzried
authors.forename: Stefan
authors.initials: S
authors.lastname: Weiss
mesh_terms: D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D001843:Bone Cements; D002484:Cementation / Q000379:methods*; D005269:Femur / Q000503:physiopathology / Q000601:surgery*; D006621:Hip Joint / Q000503:physiopathology / Q000601:surgery*; D006622:Hip Prosthesis; D006801:Humans; D007593:Joint Instability; D011475:Prosthesis Failure
chemical_list: D001843:Bone Cements