Infections associated with orthopaedic devices

Abstract Surgical site infections are a major complication of instrumented orthopaedic surgery, affecting 0.5 to 2% of patients following arthroplasty, and up to 30% of patients after fixation of open fractures. Acute infections may result from exogenous inoculation during or in the weeks following surgery (early infections), or from hematogenous seeding from a remote origin at any time after implantation (late infections). These infections are generally due to virulent organisms, such as Staphylococcus aureus, and must be treated rapidly. Delayed infections, arising between 3 and 24 months after surgery, are caused by low-virulence organisms such as coagulase-negative staphylococci. Diagnosis of delayed infections may be difficult because clinical presentation is often subtle and limited to chronic pain, and relies on imaging studies and culture of synovial fluid aspirates. Strong collaboration between surgeon, microbiologist and infectious disease specialist is essential for management of implant-associated infections, which almost always necessitates surgical intervention and prolonged antimicrobial therapy. The choice of the type of surgical intervention (debridement, or removal with or without exchange of the implant) depends on the duration of infection signs, on the pathogen species and antibiotic susceptibility, and on the patient general and local condition. Antibiotics are chosen according to pathogen susceptibility and to pharmacokinetic parameters such as bioavailability and penetration into the bone tissue. Patients treated in accordance with current guidelines are cured of their infection in 60 to 80% of cases.