Context Musculoskeletal injuries may be painful, troublesome, life limiting and also one of the global health problems. procedures in terms of bone-joint injuries (fractures-bone defects, nonunion, and spinal injuries), osteoarthritis-cartilage defects, ligament-tendon injuries, femoral head osteonecrosis and osteogenesis imperfecta. Stem cells have also Troxacitabine used in bone tissue engineering in combining with the scaffolds and provided faster and better healing of tissues. Conclusions Large amounts of preclinical studies have been made of stem cells and there is an increasing interest to perform these studies within the human population but preclinical studies are insufficient; therefore, much more and efficient studies should be conducted to evaluate the efficacy and safety of stem cells. Keywords: Stem Cells, Orthopedic Surgery, Mesenchymal Stem Cells, Adipose Derived Stem Cells, Bone Marrow Derived Stem Cells 1. Context Musculoskeletal injuries may be painful, troublesome, life limiting and also one of the global health problems. Various treatment modalities are available for treating these problems; however, the most effective method is controversial (1-3). Current Troxacitabine research has focused on identifying novel and effective methods of addressing the morbidity associated with musculoskeletal injuries. Stem cells are a promising and growing area of researches within the medical field (4). Stem cells are described as to have a potential to differentiate more than 200 different cell types in the body. They are specific cell types that can create new cells in existing healthy tissues and may help to repair tissues in those structures that are injured or damaged when they differentiate into multi lineages and becoming multipotent under appropriate conditions (5). They primarily create progenitor cells and these cells have capability of more specialized functions, such as brain cells, red blood cells, bone or cartilage (2). Among the different sources for cell therapy, mesenchymal stem cells (MSCs) are the most preferred source because they can differentiate to many different tissues, in terms of muscles, bones, fat and cartilage (6), and can be obtained from many sources, such as bone, tendon, skin, adipose tissue, umbilical cord, blood and amnion (7-11). Over the past 15 years, orthopedic surgeons have focused their attention to MSCs therapies (12, 13). There are plenty of animal studies that have successful results and there is an increasing concern about their use in human studies6. In these studies, stem cell procedures have been focused on promoting fracture healing and nonunion, regenerating articular cartilage in degenerated joints, healing ligaments or tendon injuries, and replacing degenerative vertebral disks (6). 2. Evidence Acquisition The aim of this study was to present a literature review regarding the most recent progress in stem cell procedures and current indications in orthopedics clinical care practice. The inclusion criteria for this review were all the study types related with orthopedics surgery and stem cell therapy. Studies evaluating different methods, and stem cell procedures nonrelated with orthopedic surgery were excluded. The Medline and PubMed library databases (1946 to the 15th of December 2015) were searched for the articles related with stem cell procedures in the field of orthopedic surgery and additionally the reference list of each article was also included to provide a comprehensive evaluation. 3. Results 3.1. Types of Stem Cells 3.1.1. Embryonic Stem Cells James Thompson firstly described embryonic stem cells in 1988 (14). These cells can be obtained from blastocysts during in-vitro fertilization especially on the fifth days of fetal life, and they are characterized as pluripotent cells. They can be proliferated easily in the cell culture, and differentiate into every different cell type, and thus controlling stem cell growth and differentiation is difficult. Embryonic stem cells Rabbit polyclonal to SelectinE are usually preferred for transplantation, but the rejection risk is higher. Only a limited number of animal studies have been conducted on embryonic stem cells. 3.1.2. Mature Troxacitabine Stem Cells Mature stem cells were described in the 1960s. They can be obtained from body tissues, the umbilical cord or placenta after birth and they are characterized as multipotent cells. In this type of stem cells, differentiating is limited and these cells are similar to the cells from which they originate. They are not perceived as foreign by the immune system. Tissue and organ regeneration and repair are enhanced by these cells. Stem cells are also classified into 4 types according to differentiating potential; totipotent cells are only be present in early embryo, pluripotent cells can differentiate to every cells, multipotent cells can differentiate to limited number of cells and unipotent cells are the mature form (15) (Figure 1). Figure 1. Types of Stem Cells According.