The Location of Biofilms on Chronic Prosthetic Joint Infections and the Ramifications for Clinical Practice

Revision surgery is paramount to cure chronic prosthetic joint infections because these infections are associated with biofilms on prosthetics that conventional antibiotics cannot eradicate. However, there is a paucity of research on where in vivo biofilms are located on infected prosthetics. Consequently, the objective of this pilot study was to address this gap in knowledge by staining 5 chronically infected prosthetics, that were removed at the time of revision surgery, with methylene blue. Scanning electron microscopic images were then taken of the methylene blue-stained areas to visualize biofilms. The findings show that all chronically infected prosthetics had biofilms located on the bone-prosthetic interface, yet only 2 had biofilms also located on the prosthetic interface exposed to synovial fluid. Subsequently, this pilot study provides a pathophysiological understanding of why the current treatment paradigm for chronic periprosthetic joint infection requires a revision surgery and not debridement and an implant retention surgery.