Effect of submicron polyethylene particles on an osseointegrated implant - An experimental study with a rabbit patello-femoral prosthesis

In a rabbit model of a weight bearing, articulating prosthetic joint we repeatedly injected sub-micron particles of Utra-High-Molecular-Weight-Polyethylene (UHMWPE) produced in a hip simulator. The contralateral knee with the same prosthesis was injected with carrier (NaCl) without UHMWPE, Histomorphometrical studies on undecalcified cut and ground sections at 26 and 42 weeks involved quantifications of the entire bone to metal contact and the bone area around each implant. We found no statistically significant differences between test and control groups, and the UHMWPE debris did not induce any significant osteolysis, indicating that an osseointegrated implant with a sealed interface may not be affected by UHMWPE debris or progress to aseptic loosening.