title: Mechanical properties of retrieved highly cross-linked crossfire liners after short-term implantation.
abstract: This study reports on detailed analyses of retrieved, annealed cross-linked liners. Twelve cross-linked liners (Crossfire, Stryker Orthopaedics, Mahwah, NJ) of the same Omnifit design were retrieved at revision surgery by one institution after an average 1.9 years (0.02-4.8 years) in vivo. In each case, the revision surgery was performed for reasons unrelated to wear. The mechanical properties and extent of oxidation of all inserts were characterized using a standard small punch test and measurement of the oxidation index. Results indicated that there was no association between implantation time and either mechanical properties or extent of oxidation for the inserts near the worn bearing surface. Slight variation in properties was observed as a function of sampling location, with the properties near the unworn surface displaying the greatest relative variability. We conclude that the variability in polyethylene properties observed in this small study was not clinically significant for these short-term-implanted, annealed cross-linked liners.
authors.affiliation: Implant Research Center, School of Biomedical Engineering, Science, and Health Systems, Drexel University, Philadelphia, Pennsylvania, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Kurtz
authors.forename: William
authors.initials: W
authors.lastname: Hozack
authors.forename: Joseph
authors.initials: J
authors.lastname: Turner
authors.forename: James
authors.initials: J
authors.lastname: Purtill
authors.forename: Daniel
authors.initials: D
authors.lastname: MacDonald
authors.forename: Peter
authors.initials: P
authors.lastname: Sharkey
authors.forename: Javad
authors.initials: J
authors.lastname: Parvizi
authors.forename: Michael
authors.initials: M
authors.lastname: Manley
authors.forename: Richard
authors.initials: R
authors.lastname: Rothman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D020878:Device Removal; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D019563:Mechanics; D008875:Middle Aged; D020959:Polyethylene; D011474:Prosthesis Design; D013997:Time Factors
chemical_list: D020959:Polyethylene