[Histopathological diagnostics in endoprosthesis loosening]

The implantation of total joint endoprostheses has become a routine procedure, being executed about 1.5 million times per year worldwide. The indications are osteoarthritis, rheumatic diseases, trauma and bone neoplasia. However, about 5-12% of patients develop pain and impaired function of the endoprosthesis within 10 years, necessitating revision surgery. During this operation, the so-called periprosthetic membrane between bone and prosthesis is removed. This connective tissue membrane has a pathogenetic impact on the loosening process and can be evaluated by histopathology. This article aims at elucidating the defined histomorphological criteria for the standardized diagnostics of periprosthetic membranes using a recently established classification system.