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

Pseudocapsules and interface membranes from 18 revision cases having hip prostheses with ceramic-ceramic couples and 30 autopsy specimens (6 with ceramic-ceramic couples, 7 with ceramic-polyethylene combinations and 17 with metal-polyethylene combinations) were histomorphologically analyzed, including 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, the alumina on alumina combinations showed a thinner synovial layer with reduced villous transformation and smaller infiltrates of macrophages and necroses, which can be explained by the absence of polyethylene wear. Metal-polyethylene couplings produced more than twice as many polyethylene wear particles with correspondingly more marked foreign body reaction than the ceramic-polyethylene couplings.