Basic concepts regarding fracture healing and the current options and future directions in managing bone fractures

Abstract

Fracture healing is a complex physiological process, which involves a well-orchestrated series of biological events. Repair of large bone defects resulting from trauma, tumours, osteitis, delayed unions, non-unions, osteotomies, arthrodesis and multifragmentary fractures is a current challenge of surgeons and investigators. Different therapeutic modalities have been developed to enhance the healing response and fill the bone defects. Different types of growth factors, stem cells, natural grafts (autografts, allografts or xenografts) and biologic- and synthetic-based tissue-engineered scaffolds are some of the examples. Nevertheless, these organic and synthetic materials and therapeutic agents have some significant limitations, and there are still no well-approved treatment modalities to meet all the expected requirements. Bone tissue engineering is a newer option than the traditional grafts and may overcome many limitations of the bone graft. To select an appropriate treatment strategy in achieving a successful and secure healing, more information concerning injuries of bones, their healing process and knowledge of the factors involved are required. The main goals of this work are to present different treatment modalities of the fractured bones and to explain how fractures normally heal and what factors interfere with fracture healing. This study provides an overview of the processes of fracture healing and discusses the current therapeutic strategies that have been claimed to be effective in accelerating fracture healing.

Role of Mesenchymal Stem Cells in Bone Regenerative Medicine: What Is the Evidence?

“…An ideal bone graft substitute should have certain properties, including osteoconduction, osteoinduction, osteoincorporation, osteointegration, and osteogenesis [Oryan et al, 2014a]. Despite several efforts that have been made to invent and characterize various bone graft substitutes and engineered tissue scaffolds, none could be globally accepted as an ideal alternative option to autografts due to the low ability of the bone substitutes to enhance osteoinduction and osteogenesis [Zomorodian and Eslaminejad, 2012;Mallick and Cox, 2013;Bigham-Sadegh and Oryan, 2015].…”

Mini-invasive treatment for delayed or nonunion: the use of percutaneous autologous bone marrow injection

“…M., 2013;Oryan A., 2014;Shah, 2013;Shenoy, 2014). The harvest of autologous bone marrow has been developed in previous studies (Bielecki, 2006). Since bone marrow contains osteogenic progenitors, the injection of bone marrow is considered to have the potential for effective bone regeneration (Hernigou, 2006;Undale, 2009).…”

Fish bone versus fish demineralized bone matrix (vertebra) effects on healing of experimental radial defect in rat model

“…Lateral radiographs of each group (n = 8 forelimbs) were taken post-operatively on the 1st day and then at the 35th, and 56th post-operative days to evaluate bone formation, union, and remodeling of the bone defect. The radiographs were blindly scored by a radiologist, unfamiliar with the experimental details, by the modified Lane and Sandhu scoring system (Bigham-Sadegh and Oryan 2014). At the 56th postoperative day, the rats were euthanized and the samples were obtained for histopathological (n = 4 forelimbs) and biomechanical evaluation (n = 4 forelimbs).…”

“…Allograft and xenograft have been used to solve this problem but have their own complications (Meimandi et al 2015). Allograft is a tissue that is harvested from one person and transplanted into another person of the same species (Bigham-Sadegh and Oryan 2014). Xenografts are originated from one species and transplanted to another species, for example, from fish to bovine.…”