Abstract
Ultra high molecular weight polyethylene (UHMWPE) wear debris is a major cause of long-term failure of total hip replacements. UHMWPE wear particle sizes range from submicron to several millimeters, but the particles below 10 mu m exhibit the highest biological activity.
Some in vitro wear particles, produced in joint simulators. were shown to be smaller than 0.2 mu m and recently even in vitro particles as small as several tens of nanometers have been detected. This study brings the first evidence that nano-sized wear particles with sizes below 0.05 mu m are produced in vivo.
UHMWPE wear nanoparticles were revealed by high-resolution, field emission gun scanning electron microscopy (FEGSEM) in the periprosthetic tissues of two different patients. Purity of the isolated wear nanoparticles was confirmed by energy-dispersive analysis of X-rays (EDS) and infrared spectroscopy (IR).
Morphology of wear nanoparticles was determined by image analysis of FEGSEM micrographs.