title: Topographical analysis of the femoral components of ex vivo total knee replacements.
abstract: With greater numbers of primary knee replacements now performed in younger patients there is a demand for improved performance. Surface roughness of the femoral component has been proposed as a causative mechanism for premature prosthesis failure. Nineteen retrieved total knee replacements were analysed using a non-contacting profilometer to measure the femoral component surface roughness. The Hood technique was used to analyse the wear and surface damage of the matching ultra-high molecular weight polyethylene (UHMWPE) tibial components. All femoral components were shown to be up to 11× rougher after their time in vivo while 95 % showed a change in skewness, further indicating wear. This increase in roughness occurred relatively soon after implantation (within 1 year) and remained unchanged thereafter. Mostly, this roughness was more apparent on the lateral condyle than the medial. This increased femoral surface roughness likely led to damage of the UHMWPE tibial component and increased Hood scores.
authors.affiliation: School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, NE1 7RU, England, UK. susan.scholes@ncl.ac.uk
authors.forename: Susan C
authors.initials: SC
authors.lastname: Scholes
authors.forename: Emma
authors.initials: E
authors.lastname: Kennard
authors.forename: Rajkumar
authors.initials: R
authors.lastname: Gangadharan
authors.forename: David
authors.initials: D
authors.lastname: Weir
authors.forename: Jim
authors.initials: J
authors.lastname: Holland
authors.forename: David
authors.initials: D
authors.lastname: Deehan
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Joyce
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee; D019544:Equipment Failure Analysis; D005260:Female; D005269:Femur / Q000473:pathology / Q000648:ultrastructure; D006801:Humans; D007720:Knee Prosthesis / Q000592:standards; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D008954:Models, Biological; D011095:Polyethylenes / Q000737:chemistry; D011474:Prosthesis Design; D012086:Reoperation; D013499:Surface Properties; D013977:Tibia / Q000473:pathology / Q000648:ultrastructure
chemical_list: D011095:Polyethylenes; C111601:ultra-high molecular weight polyethylene