Experimental study of β-TCP scaffold loaded with VAN/PLGA microspheres in the treatment of infectious bone defects

Antibiotic bone cement filling technology has been widely used in the treatment of infectious bone defects for decades. However, the current treatment requires multiple complicated procedures, which would lead to pain and financial burden for patients. Repairing bone defects and control infection at the same time is the pain spot of orthopaedic area. In this study, we develop a composite scaffold that aiming at effectively repair infectious bone defects simultaneously. Vancomycin hydrochloride(Van) /Poly(lactic-co-glycolic) acid(PLGA) microspheres prepared by double emulsion method were successfully loaded into β-tricalcium phosphate scaffold through electrostatic and physical crosslinking. Full characterization, including mechanical properties, biocompatibility, in vitro release profile and antibacterial properties of the composite scaffolds(CPSFs) were performed. The rabbit osteomyelitis model based on big hole and small hole methods was established. Pharmacodynamics study, including the local bacteriostatic and osteogenic ability were evaluated by X-ray, Micro-CT and histopathology at 4 months after surgery. These findings indicate that a reliable rabbit model of local bone defect infection successfully established by big hole approach. The CPSFs with significant histocompatibility and biocompatibility could sustained release vancomycin for extended duration. It exhibited great application potential in clinical aim at the indication of local infectious bone defects.