<i>In vivo</i> application of prevascularized bone scaffolds: A literature review

BACKGROUND: Despite expanding research, the development of materials for replacing bone defects remains an urgent problem in orthopedics and traumatology. Thus, one of the most important tasks is to create conditions for proper trophicity of the bone implant. AIM: To analyze modern approaches to bone scaffold vascularization and evaluate their adequacy in in vivo models. MATERIALS AND METHODS: The article presents a literature review dedicated to the methods of vascularization of bone scaffolds. A literature search was performed in PubMed, ScienceDirect, eLibrary, and Google Scholar databases from 2013 to 2023 using keywords, and 271 sources were identified. After exclusion, 95 articles were analyzed, and the results of 38 original studies and one literature review were presented. RESULTS: Regardless of the initial vascularization method of scaffolds, bone implants show distinct osteoinductive features and promote advanced bone tissue regeneration. Constructs based on solid polymers and calcium–phosphate compositions also perform osteoconductive functions. Mesenchymal stem cells are used as the main cell type, as well as vessel-type cells, which in cooperation also have a positive effect on bone-defect remodeling. Bone morphogenetic proteins are used for directed differentiation in the osteogenic direction, and vascular endothelial growth factor is used for differentiation in the vascular pathway. CONCLUSIONS: At present, no method for vascularization of scaffolds has been approved universally. In addition, no evidence supported the comparative effectiveness of vascularization methods, whereas animal model studies have demonstrated a positive effect of prevascularized patterns on the recovery rate of minor and critical defects.