The relationship between shelf life and in vivo wear for polyethylene acetabular liners.
Abstract: Although laboratory studies have correlated shelf life for gamma-irradiated-in-air polyethylene with material degradation, it is unknown whether this clinically affects wear. Therefore, we examined the relationship between shelf life and clinical wear for 152 gamma-irradiated-in-air acetabular liners. True wear rates were calculated from computer-assisted head penetration analyses of serial radiographs. Follow-up averaged 6.6 years. Shelf life averaged 11.8 months with 96% of liners having shelf lives of less than 3 years. Data analysis revealed no correlation between shelf life and true wear rates (r2 = 0.002; P = .60). This study provides useful information for surgeons concerned about shelf life as a potential cause of high wear in previously implanted components. For conventional liners in inventory less than 3 years, we found no evidence of increased wear in vivo.
Sychterz
Christi J
CJ
Anderson Orthopedic Research Institute, PO Box 7088, Alexandria, VA 22307, USA.
Young
Anthony M
AM
Orishimo
Karl
K
Engh
Charles A
CA
D000077:Acetabulum; D019644:Arthroplasty, Replacement, Hip; D005260:Female; D005720:Gamma Rays; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D020959:Polyethylene / Q000528:radiation effects; D011475:Prosthesis Failure; D013242:Sterilization; D013997:Time Factors
D020959:Polyethylene