HIGHLY CROSSLINKED POLYETHYLENES: IMPROVED WEAR OR PARADOX?

摘要

Lubrication and wear of artificial joints are important issues for their longevity. Bone loss caused by the biological response to the wear debris (osteolysis) leads to implant loosening and eventual failure of the device. Investigators have shown that the size, shape, and number of particles are factors in the osteolytic response of wear debris. It has been demonstrated that both submicron size particles and long fibrils can stimulate macrophage responses resulting in osteolytic reactions. Several simulator studies with total hip replacements have shown greatly reduced wear in crosslinked polyethylene (XLPE) compared with conventional polyethylene (PE). This paper examines the known database on XLPE concerning the wear and particulate debris. It has been shown that the size of the XLPE debris particles is much smaller than for conventional PE. Paradoxically, the decreased wear of XLPE should decrease the osteolytic potential, but the decreased debris size may increase the biological activity.