METAL CARCINOGENESIS IN TOTAL JOINT ARTHROPLASTY - ANIMAL-MODELS

As early as 1956, laboratory investigations into the carcinogenicity o f modern dental and orthopaedic alloys were undertaken. Such studies w ere prompted by the observation that workers, particularly in nickel a nd chromate refining, had increased risks of nasal and lung tumors. Fo r the past 25 years, sporadic case reports have documented the develop ment of malignant neoplasms proximate to an orthopaedic implant, Altho ugh the results of epidemiologic studies have not shown an excessive n umber of tumors in patients receiving stainless steel or superalloy im plants, the possibility of carcinogenesis, given the corrosive environ ment in which metal implants exist, has prompted ongoing laboratory st udies. Leaching of metal ions from implants, the synovial processing o f metallic wear debris, and the effects of exposure to intraarticular metal particles have been the subjects of numerous laboratory studies. The results of these studies are summarized and recommended parameter s for future laboratory investigations are given.