Hylamer wear rates and shelf life : A clinical correlation


Published online: Aug 27 2005

Paul D. KIELY, James A. HARTY, John P. MCELWAIN

From the Adelaide and Meath Hospital, Dublin, Ireland

Abstract

We evaluated the performance of 84 Hylamer polyethylene components and zirconia modular femoral heads which were implanted in a single institution over a 5 year period. Patients were followed up for a mean of 6.2 years. The mean rate of penetration was 0.58 mm/year (0.05-1.0). Lot/batch numbers were available in the clinical case notes of 54 patients. Using the lot/ batch numbers, we were able to determine the Hylamer cups' shelf lifes. We found that liners with a shelf life greater than 10 months had a significantly greater linear wear (0.38 mm/year) than those implanted in less than 10 months (0.05 mm/year).