[Histomorphological and spectroscopic studies on the skeleton following alloplastic joint substitution (author's transl)].

We report on our morphological and spectrometric findings with complete acetabuloplastics. The histomorphological investigation revealed the formation of a narrow cicatricial coat round the prothesis. The collagenous tissue borders on a zone of granulation tissue of varying width. Granular foreign matter can be found in cicatrical tissue especially in the extracellular space and in granulation tissue in macrophages. Only a few partigles turned out to be iron in the Prussian blue reaction. Spectral analysis proved the hip and thigh-bones to contain more than 0.001 p. c. of cobalt and chrome. Toxicological problems inherent in the use of the cobalt alloy "Vitallium" are discussed. The dangers of metal poisoning are dealt with in addition to those of the development of osteomyelitis and the formation of a sarcoma. At last we discuss our macroscopic findings concerning the fit of the prosthesis, the metal demonstration by electron micrsocopy, and the scanning electron microscopic investigation of the metal surfaces.