Evaluation of implant sonication as a diagnostic tool in implant-associated infections

Infections of implants pose a severe problem in the field of orthopedic surgery, because they can cause bone degradation with subsequent loosening of the implant. The discrimination between septic implant loosening and aseptic loosening can be a challenge, and hence novel diagnostic methods have been introduced to improve the detection of bacteria. Because a major problem is their firm adherence to implants due to biofilm formation, sonication has been introduced, followed by identification of bacteria by culture or genetic methods. In this study, we compared the results obtained after sonication pretreatment with those of microbiological testing of tissue samples and histopathological evaluation of the same tissue. Furthermore, we related the results obtained following sonication to the clinical diagnosis of septic or aseptic implant loosening, respectively. Sonication of explanted devices also enhances the likelihood of detecting bacterial growth in patients who were considered "aseptic" based on the clinical evaluation.