title: The influence of surface roughness on stem-cement gaps.
abstract: We have compared the interface morphology at the stem-cement interface of standard Charnley stems with a satin finish (Ra = 0.75 microm) with identical stems which had been grit-blasted over their proximal third (Ra = 5.3 microm) to promote a proximal bond. The stems were cemented into cadaver femora using conventional contemporary cementing techniques. After transverse sectioning, we determined the percentage of the perimeter of the stem which had a gap at the interface. There were substantial gaps (mean 31.4 +/- 17.1%) at the stem-cement interface in the grit-blasted region. This fraction was significantly (paired t-test, p = 0.0054) higher than that found around the contralateral satin-finished stems (mean 7.7 +/- 11.7%). Although studies of isolated metal-cement interfaces have shown that the bond strength can increase with surface roughness it cannot be assumed that this effect will be observed under clinical conditions.
authors.affiliation: Institute for Human Performance, Musculoskeletal Science Research Centre, SUNY Upstate Medical University, Syracuse, New York 13210, USA.
authors.forename: A
authors.initials: A
authors.lastname: Race
authors.forename: M A
authors.initials: MA
authors.lastname: Miller
authors.forename: D C
authors.initials: DC
authors.lastname: Ayers
authors.forename: R J
authors.initials: RJ
authors.lastname: Cleary
authors.forename: K A
authors.initials: KA
authors.lastname: Mann
mesh_terms: D000704:Analysis of Variance; D001843:Bone Cements; D002102:Cadaver; D005269:Femur; D006622:Hip Prosthesis; D006801:Humans; D008854:Microscopy, Electron; D011475:Prosthesis Failure; D013499:Surface Properties
chemical_list: D001843:Bone Cements