Pathogenesis and treatment concepts of orthopaedic biofilm infections

Implant-associated infection is caused by surface-adhering bacteria persisting as biofilm. Periprosthetic joint infection is difficult to diagnose and treat. The high susceptibility of implanted devices to infection is because of a locally acquired host defense defect, and persistence is mainly because of the rapid formation of a biofilm resistant to host defense and antimicrobial agents. Successful treatment of periprosthetic joint infection requires the optimal surgical procedure combined with long-term antimicrobial therapy directed against surface-adhering microorganisms. Surgical treatment according to an algorithm has been validated in several observational studies. The role of rifampin against device-associated staphylococcal infection has been evaluated in an animal model, in observational studies and in a controlled trial. Given the limited efficacy of traditional antibiotics in implant-associated infections, novel strategies such as coating of the device, vaccination against biofilms, and quorum-sensing inhibitors are promising future options for prevention and treatment.