Efficacy of Antibiotic-loaded Poly (Methyl Methacrylate) Beads in Orthopaedic Infections

Abstract

Introduction: Bone infections are associated with morbidity and mortality. Infection control is achieved by surgical debridement and microbial-specific antibiotic administration. Antibiotic Loaded Bone Cement (ALBC) has been accepted as a mode of treatment since systemic antibiotics alone are associated with higher recurrence and reoperation rates. Aim: To assess the efficacy of ALBC in the treatment of orthopaedic infections. Materials and Methods: A retrospective case series of 59 patients, treated for chronic musculoskeletal infections between January 2007 to December 2013, were included. They were divided into five groups; 1) Open fractures (21 patients); 2) Closed fractures (5 patients); 3) Infected nonunion (26 patients); 4) Infected implants (6 patients); and 5) Chronic osteomyelitis (1 patient). Results: The median age at presentation was 34.8 years (range, 18.0-58.0). Five patients were lost to follow-up. In the 54 patients analysed, infection was controlled in all patients (100%) with debridement/implant exit and antibiotic beads. 31 patients (57%) united or were infection free with the primary procedure. This included all the patients in Group 4 and 5, six patients in Group 1 and 18 patients in Group 3. 23 patients (43%) underwent additional procedures to achieve bony union after the infection control. Gram-Negative Organisms (GNB) were isolated in 36% (21 cases), whereas Methicillin Resistant Staphylococcus Aureus (MRSA) was found in 12% (7 cases). The average healing time for GNB and MRSA infections was 19.4 months and eight months respectively. Conclusion: The ALBC is effective in controlling infection. Infections caused by gram-negative bacteria are becoming common and they resolve later than MRSA infections.

Keywords

• antibiotic bone cement
• chronic osteomyelitis
• gram negative bacteria
• infected non-union
• open fractures