title: The effect of surface morphology on the primary fixation strength of uncemented femoral knee prosthesis: a cadaveric study.
abstract: We investigated the effect of surface morphology on the mechanical performance of uncemented femoral knee prosthesis. Eighteen implants were implanted on nine paired femurs and then pushed-off (left legs: a novel surface morphology; right legs: Porocoat as baseline). Bone mineral density (BMD) and anteroposterior dimension were not significantly different between groups. The insertion force was not significantly different, however, the loosening force was significantly higher in the novel group (P=0.007). BMD had a direct relationship with the insertion and loosening force (P<0.001). The effect of surface morphology on implant alignment was very small. We conclude that the surface properties create a higher frictional resistance, thereby providing a better inherent stability of implants featuring the novel surface morphology.
authors.affiliation: Orthopaedic Research Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Sanaz
authors.initials: S
authors.lastname: Berahmani
authors.affiliation: Orthopaedic Research Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands.
authors.forename: Dennis
authors.initials: D
authors.lastname: Janssen
authors.affiliation: DePuy Synthes Joint Reconstruction, Leeds, UK.
authors.forename: David
authors.initials: D
authors.lastname: Wolfson
authors.affiliation: DePuy Synthes Joint Reconstruction, Warsaw, Indiana.
authors.forename: Kori
authors.initials: K
authors.lastname: Rivard
authors.affiliation: Department of Orthopaedics, Radboud University Medical Center, Nijmegen, Netherlands.
authors.forename: Maarten
authors.initials: M
authors.lastname: de Waal Malefijt
authors.affiliation: Orthopaedic Research Laboratory, Radboud University Medical Center, Nijmegen, The Netherlands; Laboratory for Biomechanical Engineering, University of Twente, Enschede, The Netherlands.
authors.forename: Nico
authors.initials: N
authors.lastname: Verdonschot
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D001696:Biomechanical Phenomena; D002102:Cadaver; D002484:Cementation; D005260:Female; D005269:Femur / Q000033:anatomy & histology* / Q000601:surgery*; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008953:Models, Anatomic; D011475:Prosthesis Failure
keywords: anteroposterior dimension; bone mineral density; insertion force; primary fixation strength; surface morphology; uncemented femoral knee prosthesis