Morphologic characteristics of periprosthetic tissues from hip prostheses with ceramic-ceramic couples - A comparative histologic investigation of 18revision and 30 autopsy cases

Pseudocapsules and interface membranes from 18 revision cases having hip pr ostheses with ceramic-ceramic couples and 30 autopsy specimens (6 with cera mic-ceramic couples, 7 with ceramic-polyethylene combinations and 17 with m etal-polyethylene combinations) were histomorphologically analyzed, includi ng a semiquantitative grading of the wear particles and histologic changes. Unlike the revision cases, which usually showed ceramic wear particles in the adjacent tissues, only half of the autopsy cases revealed ceramic wear. As compared to the ceramic-polyethylene and metal-polyethylene couples, th e alumina on alumina combinations showed a thinner synovial layer with redu ced villous transformation and smaller infiltrates of macrophages and necro ses, which can be explained by the absence of polyethylene wear. Metal-poly ethylene couplings produced more than twice as many polyethylene wear parti cles with correspondingly more marked foreign body reaction than the cerami c-polyethylene couplings.