Comparison of Steady State Femoral Head Penetration Rates Between Two Highly Cross-Linked Polyethylenes in Total Hip Arthroplasty

London Health Sciences Center, Rossett, Wrexham, UK.
The Journal of arthroplasty (Impact Factor: 2.37). 08/2009; 25(5):680-6. DOI: 10.1016/j.arth.2009.05.006
Source: PubMed

ABSTRACT Given that the manufacture of highly cross-linked polyethylene (HXLPE) is not standardized, the behavior of these materials may vary. Our study compares minimum 5-year steady state femoral head penetration rates using the Martell method, in 2 HXPLEs produced by different manufacturers. Patients received a primary hip arthroplasty using an uncemented acetabular component with an HXLPE liner and a 28-mm femoral head. Forty-seven patients in group A received an HXLPE liner (Reflection XLPE, Smith and Nephew Inc, Memphis, Tenn), and 36 patients in group B received a different HXLPE liner (Longevity, Zimmer Inc, Warsaw, Ind). Average follow-up was 6.42 years in group A and 7.64 years in group B. The steady state head penetration rates were not significantly (P > .05) different between the HXPLE groups over the midterm with 0.026 mm/y and 0.025 mm/y in groups A and B, respectively.

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