CHALLENGE TO THE CONCEPT THAT UHMWPE ACETABULAR COMPONENTS OXIDIZE IN-VIVO

Severe wear of the ultra-high molecular weight polyethylene (UHMWPE) c omponents of total joint replacements limits their long-term success. In previous studies, the infrared spectra obtained on retrieved UHMWPE components were interpreted as evidence that the UHMWPE oxidizes in v ivo. In direct contrast, infrared spectroscopy of the retrieved UHMWPE acetabular components examined in this study demonstrated adsorbed es terified fatty acids, readily extractable by hexane, and no substantia l evidence of in vivo oxidation. This emphasizes that special care mus t be taken when using infrared spectroscopy to assess retrieved compon ents.