The effect of low-viscosity cement on mantle morphology and femoral stem micromotion: a cadaver model with simulated blood flow.
BACKGROUND
Limited data exist on the performance of low-viscosity cement in clinically realistic cadaver models.


METHODS
Paired stem/cement/femur constructs were generated with low-viscosity and standard-viscosity cements. The constructs were created and tested under simulated in vivo conditions, for which novel techniques were developed during this study. Mantle function was quantified by stem/cortex micromotions over 105cycles of "stair-climbing". Mantle morphology was determined from transverse sections.


RESULTS
Penetration of low-viscosity cement was greater proximally but less distally (p = 0.02). Low-viscosity cement resulted in more stem retroversion (p = 0.04), but there was no difference in subsidence (p = 0.4). Low-viscosity cement mantles had greater fractions of non-apposed interface (p = 0.006). Fraction of non-apposed interface predicted stem retroversion (R2 = 0.64, p = 0.002).


CONCLUSIONS
Low-viscosity cement resulted in inferior cement mantles. Early micromotion was reduced by better interface apposition. The greater stem retroversion of low-viscosity cement would probably lead to higher revision rates. Early stem migration is due to interface non-apposition. Techniques should be developed to reduce non-apposition of cemented interfaces.
Race
Amos
A
SUNY Upstate Medical University, Syracuse, NY 13210, USA. racea@upstate.edu
Miller
Mark A
MA
Clarke
Michael T
MT
Mann
Kenneth A
KA
Higham
Paul A
PA
D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001696:Biomechanical Phenomena; D001843:Bone Cements; D002102:Cadaver; D005269:Femur / Q000098:blood supply / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D008422:Materials Testing; D008954:Models, Biological; D014783:Viscosity
D001843:Bone Cements