title: [Histopathological investigations in soft tissue surrounding metallic orthopaedic implants by extravasated eosinophil leukocytes].
abstract: BACKGROUND
  The amount of extravasated eosinophil leukocytes in soft tissue surrounding a metallic orthopaedic implant indirectly allows conclusions about the allergenicity of the implant. As yet the implications of the distance of the biopsy from the implant have not been studied.
  
  
  METHODS
  In a prospective study we histocytologically evaluated soft tissue biopsies gained during routine removal of orthopaedic implant material in 81 patients. By means of a quantitative and semiquantitative method, material directly adjacent to and 1 cm distant from the implant was examined for eosinophil leukocytes.
  
  
  RESULTS
  In respect to the number of eosinophil granulocytes, the two groups showed no significant discrepancies (p = 0.55). lnterestingly, correlation analysis revealed a significant difference in the number of eosinophiles between implant-adjacent and -distant tissue in some individuals. Consecutive semiquantitative analysis could show that there was no correlation concerning the number of eosinophiles between results gained at 1 cm distance from the implant and material in the direct vicinity of the biomaterial.
  
  
  CONCLUSIONS
  Our results suggest that when utilising a histocytological method to determine metal sensitivity of a biomaterial on surrounding soft tissue, not only material directly adjacent to the implant but also at a distance of approximately 1 cm should be evaluated.
authors.affiliation: Klinik und Poliklinik für Orthopädie der Universität Bonn, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Gassel
authors.forename: U A
authors.initials: UA
authors.lastname: Wagner
authors.forename: C
authors.initials: C
authors.lastname: Kraft
authors.forename: P
authors.initials: P
authors.lastname: Conrads
authors.forename: O
authors.initials: O
authors.lastname: Schmitt
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002648:Child; D002675:Child, Preschool; D020878:Device Removal; D004802:Eosinophilia / Q000473:pathology*; D004804:Eosinophils / Q000473:pathology; D005260:Female; D005549:Foreign-Body Reaction / Q000473:pathology*; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D019736:Prostheses and Implants