Foreign body reaction to polymeric debris following total hip arthroplasty.

: Two cases of severe foreign body reaction to polymeric debris occurred following cemented total hip arthroplasty. The debris consisted of microfragments of both polyethylene and polymethylmethacrylate. Microfragments are believed to be primarily responsible for the extensive lytic reactions, which represent an extreme degree of the chronic inflammatory response that is commonly associated with loosening of cemented total hip arthroplasties. A schematic representation of the pathogenesis of component loosening, including the foreign body reaction, illustrates the relationship of this phenomenon to the general problem of aseptic loosening. Revision arthroplasty was successful in both cases, followed for a period of nine and 16 months, respectively.