With the development of social economy, high-intensity energy is the direct cause of fracture, such as traffic accident, fall injury and tumble. Fracture healing is affected by many factors, such as malunion, delayed union, nonunion and wound infection. Tibial fractures are usually caused by high-energy mechanisms and can also be caused by low-energy mechanisms of ankle rotation. With the gradual deepening of orthopedic surgeons′ understanding of bone nonunion, the treatment of tibial nonunion is mainly divided into surgical treatment and non-operative treatment. Surgical treatment is generally the first choice for the treatment of bone nonunion, in which plate internal fixation plays an unique advantage in the treatment of tibial nonunion. By reviewing the recently published literature, this paper reviews the latest progress in the treatment of tibial nonunion with plate internal fixation.

Objective:To investigate the basic characteristics and treatment of aseptic nonunion of femoral shaft in Xi'an Red Cross Hospital from 2013 to 2020.Methods:The data were analyzed retrospectively of the patients with aseptic nonunion of femoral shaft who had been treated at Department of Orthopaedics and Trauma, Red Cross Hospital Affiliated to Medical College, Xi'an Jiaotong University from January 2013 to December 2020. The patients' data from 2013 to 2016 were assigned into group A while those from 2017 to 2020 into group B. The data like gender, age and nonunion were statistically analyzed and compared between the 2 groups.Results:A total of 311 patients with aseptic nonunion of femoral shaft were diagnosed and treated during the 8 years, accounting for 54.6% (311/570) of the femur nonunion, 32.8% (311/949) of the lower extremity nonunion, 25.0% (311/1,242) of the extremity nonunion, and 22.7% (311/1,370) of the whole body nonunion. There were 244 males and 67 females; the majority of patients were in the age group of 21 to 50 (67.2%, 209/311). The occupation distribution was the most common in farmers (49.2%, 153/311). Traffic injury was the most common cause for primary fractures (40.8%, 127/311). The most common type of injury was closed injury (89.4%, 278/311); the most common type of nonunion was atrophic nonunion (87.8%, 273/311); intramedullary nailing was the main treatment for primary fractures (54.3%, 169/311); channel osteogenesis was the main treatment for secondary nonunion (62.1%, 193/311); autologous iliac bone grafting was the most common grafting for atrophic nonunion (83.5%, 228/311). Compared with group A, the proportion of aseptic nonunion of femoral shaft in group B increased by 9.2% in the femoral nonunions, by 6.9% in the lower extremity nonunions, and by 6.0% in the extremity nonunions, and by 5.2% in the whole body nonunions, showing statistically significant differences ( P < 0.05). There were significant differences in the types of nonunion, occupational distribution, first-stage fracture treatment, second-stage nonunion treatment, and bone grafting method between the 2 groups ( P < 0.05). Conclusions:The patients with aseptic nonunion of the femoral shaft were more common in young and middle-aged male heavy manual laborers, and the condition was increasing in recent years. The channel osteogenesis technique was still the preferred treatment method in the hospital investigated.

Nonunion of femur is a common complication after intramedullary nail operation of femoral fracture, with an incidence of 1% to 12.5%. At present, the treatment of femoral nonunion is mainly divided into surgical treatment and non-operative treatment, and surgical treatment is the first choice. The gold standard for surgical treatment of femoral nonunion is replacement of intramedullary nail, but for non-isthmus femoral nonunion, larger diameter intramedullary nail could not solve the problem of rotation and angular displacement of the broken end of nonunion. For malnourished nonunion, atrophic nonunion and bone nonunion with large bone defect, the replacement of intramedullary nail and autogenous bone graft are not enough to eliminate the gap between the broken ends and increase the contact area between the broken ends. It cannot provide a good biological environment for the broken ends. Because the replacement of intramedullary nail does not expose the broken ends of bone nonunion, and the corresponding tissue cannot be taken for bacteriological culture, so it is difficult to judge whether the broken end sare complicated with infection. The double plate technique is to find the site of bone nonunion under direct vision, and two plates are placed with different angles. This paper reviews the literature related to the treatment of femoral nonunion with double plate technique published at home and abroad in the past 10 years, and concludes that double plate fixation combined with autogenous iliac bone graft provides a three-dimensional fixation model for the healing of nonunion. It has the characteristics of strong stability and plays an active role in improving the biological behavior and mechanical stability of the fracture ends. The operation is beneficial to the flexion and extension of the knee joint, with the characteristics of high healing rate, low complication rate, effective pain relief and so on.

BACKGROUND: Implantation of bone marrow mesenchymal stem cells (BMSCs) is a potential alternative for promoting bone defects healing or osseointegration in osteoporosis. However, the reactive oxygen species (ROS) accumulated and excessive inflammation in the osteoporotic microenvironment could weaken the self-replication and multi-directional differentiation of transplanted BMSCs. METHODS: In this study, to improve the hostile microenvironment in osteoporosis, Poloxamer 407 and hyaluronic acid (HA) was crosslinked to synthetize a thermos-responsive and injectable hydrogel to load MnO2 nanoparticles as a protective carrier (MnO2 @Pol/HA hydrogel) for delivering BMSCs. RESULTS: The resulting MnO2 @Pol/HA hydrogel processed excellent biocompatibility and durable retention time, and can eliminate accumulated ROS effectively, thereby protecting BMSCs from ROS-mediated inhibition of cell viability, including survival, proliferation, and osteogenic differentiation. In osteoporotic bone defects, implanting of this BMSCs incorporated MnO2 @Pol/HA hydrogel significantly eliminated ROS level in bone marrow and bone tissue, induced macrophages polarization from M1 to M2 phenotype, decreased the expression of pro-inflammatory cytokines (e.g., TNFa, IL-1b, and IL-6) and osteogenic related factors (e.g., TGF-b and PDGF). CONCLUSION This hydrogel-based BMSCs protected delivery strategy indicated better bone repair effect than BMSCs delivering or MnO2 @Pol/HA hydrogel implantation singly, which providing a potential alternative strategy for enhancing osteoporotic bone defects healing.

Yeast autolysis affects the flavor and quality of beer. The regulation of yeast autolysis is a need for industrial beer production. Previous studies on brewer's yeast autolysis showed that the citric acid cycle-related genes had a great influence on yeast autolysis. To explore the contribution of isocitrate dehydrogenase genes in autolysis, the IDP1 and IDP2 genes were destroyed or overexpressed in typical lager yeast Pilsner. The destruction of IDP1 gene improved the anti-autolytic ability of yeast, and the anti-autolytic index after 96 h autolysis was 8.40, 1.5 times higher than that of the original strain. The destruction of IDP1 gene increased the supply of nicotinamide adenine dinucleotide phosphate (NADPH) and the NADPH/NADP⁺ ratio was 1.94. After fermentation, intracellular ATP level was 1.8 times higher than that of the original strain, while reactive oxygen species (ROS) was reduced by 10%. The destruction of IDP2 gene resulted in rapid autolysis and a decrease in the supply of NADPH. Anti-autolytic index after 96 h autolysis was 4.03 and the NADPH/NADP⁺ ratio was 0.89. After fermentation, intracellular ATP level was reduced by 8% compared with original strain, ROS was 1.3 times higher than that of the original strain. The results may help understand the regulation mechanism of citric acid cycle-related genes on yeast autolysis and provide a basis for the selection of excellent yeast with controllable anti-autolytic performance.
Humans ; Isocitrate Dehydrogenase/genetics* ; NADP ; Reactive Oxygen Species ; Autolysis ; Adenosine Triphosphate