title: The pin-bone interface in external fixator: a standardized analysis in a sheep osteotomy model.
abstract: OBJECTIVE
  The hypothesis of the study was that the incidence of pin loosening and pin infection would increase, whereas the general stability of the pin-bone interface would decrease with ongoing implantation time. The aim of this study was to analyze the biologic reactions of the bone tissue adjacent to the pin to determine the relationship among the osseous anchorage of pins, the incidence of infections, and the histologic appearance.
  
  
  METHODS
  Three groups of sheep received a tibial osteotomy stabilized by external fixators. The pin-bone interface was analyzed biomechanically, radiologically, microbiologically, and histologically after 3, 6, and 9 weeks.
  
  
  CONCLUSIONS
  Contrary to common opinion, pin anchorage was not altered biomechanically throughout the 9 weeks of the study. This effect might be attributed to an increasing remodeling found in the callus and cortex around the pins and was likely assisted by a strict pin care routine and a low infection rate.
authors.affiliation: Julius Wolff Institut and Center for Musculoskeletal Surgery, Charité-Universitätsmedizin Berlin, Berlin, Germany.
authors.forename: Hanna
authors.initials: H
authors.lastname: Schell
authors.forename: Theresa
authors.initials: T
authors.lastname: Reuther
authors.forename: Georg N
authors.initials: GN
authors.lastname: Duda
authors.forename: Jasmin
authors.initials: J
authors.lastname: Lienau
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D001858:Bone Nails / Q000382:microbiology; D016267:External Fixators / Q000382:microbiology; D005260:Female; D015994:Incidence; D023421:Models, Animal; D010027:Osteotomy / Q000379:methods*; D011859:Radiography; D012756:Sheep; D013530:Surgical Wound Infection / Q000453:epidemiology; D013977:Tibia / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*