THA with Highly Cross-linked Polyethylene in Patients 50 Years or Younger

Abstract

Highly cross-linked polyethylene has been associated with low in vitro wear, but also has decreased in vitro ultimate yield strength. We therefore asked whether highly cross-linked polyethylene would result in lower outcome scores, wear, or early failure in a young patient population. Seventy THAs in 64 patients were performed using a highly cross-linked (electron beam-irradiated to 9 Mrads) acetabular liner and a cobalt-chrome femoral head. The average age of the patients at surgery was 41 years (range, 19-50 years). The minimum followup was 2.4 years (average, 4 years; range, 2.4-6.5 years). We recorded demographic and clinical data, including Harris hip score. Polyethylene wear measurements were analyzed with a validated, computer-assisted, edge detection method. The average Harris hip score improved from 53 to 92 at last followup. There was no evidence of acetabular or femoral loss of fixation, subsidence, or loosening. Linear wear was undetectable at this followup interval. No patient experienced catastrophic failure or underwent revision surgery. These data show low polyethylene wear rates and no catastrophic failures at early followup in a young patient cohort.

Continued Improved Wear with an Annealed Highly Cross-linked Polyethylene

“…Rajadhyaksha et al, also comparing Crossfire with a control group of N 2 Vac polyethylene, noted a difference in lysis similar to ours (0% versus 14.8%) [23]. Some studies reported no difference in osteolytic lesions between the HXLPE and control (even with differences in head penetration), but noted their followups were short and that more time may be required for differences to manifest [2,4,9,19,20,27].…”

Function and Fixation of Total Hip Arthroplasty in Patients 25 Years of Age or Younger

“…Our data indicate contemporary THA provides improved hip function and stable implant fixation at short-to midterm followup. All bearing surface failures were the result of conventional polyethylene wear and/or osteolysis, which suggests future studies should investigate the performance of alternative bearing materials [25]. Cementless fixation combined with improved THA bearing materials may provide long-term survivorship even in the young patient population.…”

Long-Term Results of Total Hip Arthroplasty with 28-Millimeter Cobalt-Chromium Femoral Heads on Highly Cross-Linked Polyethylene in Patients 50Years and Less

“…A radiograph taken between 12-18 months after surgery was used as a baseline for the measurement of steady-wear rate to account for bedding-in of the liner within the acetabular shell [50]. The resultant data was processed using the two measurements approach as described by Shia et al [46]. Volumetric wear is calculated from the magnitude of the wear vector on the two-dimensional projection on AP radiograph and the direction of the wear with respect to the cup face and the femoral head size [24, 36].…”