title: Prevention of pin tract infection with titanium-copper alloys.
abstract: The most frequent complication in external fixation is pin tract infection. To reduce the incidence of implant-associated infection, many published reports have looked at preventing bacterial adhesion by treating the pin surface. This study aimed to evaluate the antibacterial activity of a Titanium-Copper (Ti-Cu) alloy on implant infection, and to determine the potential use of the Ti-Cu alloy as a biomaterial. Two forms of Ti-Cu alloys were synthesized: one with 1% Cu and the other with 5% Cu. For analyzing infectious behavior, the implants were exposed to Staphylococcus aureus and Escherichia coli. The reaction of pathogens to the Ti-Cu alloys was compared with their reaction to stainless steel and pure titanium as controls. Both Ti-Cu alloys evidently inhibited colonization by both bacteria. Conversely, cytocompatibility studies were performed using fibroblasts and colony formation on the metals was assessed by counting the number of colonies. Ti-1% Cu alloy showed no difference in the number of colonies compared with the control. External fixator pins made of Ti-Cu alloys were evaluated in a rabbit model. The tissue-implant interactions were analyzed for the presence of infection, inflammatory changes and osteoid-formation. Ti-1% Cu alloy significantly inhibited inflammation and infection, and had excellent osteoid-formation. Copper blood levels were measured before surgery and at 14 days postoperatively. Preoperative and postoperative blood copper values were not statistically different. Overall, it was concluded that Ti-Cu alloys have antimicrobial activity and substantially reduce the incidence of pin tract infection. Ti-1% Cu alloy shows particular promise as a biomaterial.
authors.affiliation: Department of Orthopaedic Surgery, Kanazawa University, Kanazawa 920-8641, Japan.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Shirai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Tsuchiya
authors.forename: Tohru
authors.initials: T
authors.lastname: Shimizu
authors.forename: Kaori
authors.initials: K
authors.lastname: Ohtani
authors.forename: Yo
authors.initials: Y
authors.lastname: Zen
authors.forename: Katsuro
authors.initials: K
authors.lastname: Tomita
mesh_terms: D000497:Alloys / Q000737:chemistry*; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry; D001424:Bacterial Infections / Q000517:prevention & control*; D001672:Biocompatible Materials / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D006224:Cricetinae; D003412:Cricetulus; D016267:External Fixators / Q000009:adverse effects / Q000382:microbiology; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D008422:Materials Testing; D011817:Rabbits; D013193:Stainless Steel / Q000737:chemistry; D014025:Titanium / Q000737:chemistry*
chemical_list: D000497:Alloys; D000890:Anti-Infective Agents; D001672:Biocompatible Materials; D013193:Stainless Steel; D003300:Copper; D014025:Titanium