The effects of intravenous and local tranexamic acid on bone healing: An experimental study in the rat tibia fracture model

A new method regulates bone fracture tissue exosome lncRNA-mRNA to promote mesenchymal stem cell proliferation and migration

Post-injury adaptation (PIA) is a simple and convenient method to promote bone healing, but its mechanism is unclear. This study was to discuss the role of fracture site tissue exosomes lncRNAs-mRNAs networks on PIA promoting bone mesenchymal stem cells (BMSCs) proliferation and migration. Firstly, the effects of PIA accelerating BMSCs proliferation and migration were confirmed by rat fracture model and bone fracture environment in vitro. Besides, the fracture site tissue exosomes were isolated and authenticated. Then the tissue exosomes were the key factor in PIA promoting BMSCs proliferation and migration authenticated by in vitro and in vivo experiments. The high throughput sequencing and RT-PCR were used to analyze the tissue exosomes lncRNAs-mRNAs networks. It was found that PIA treatment upregulated 118 lncRNAs, 295 mRNAs, and downregulated 111 lncRNAs, 2706 mRNAs in tissue exosomes. A total 12,211 genes were the target genes. Akt1, Actb and Uba52 were the hub mRNAs in tissue exosomes. In additions, tissue-derived exosomes of PIA treated rats upregulated 49 genes, 3 lncRNAs and downregulated 28 genes, 1 lncRNA in BMSCs. Kif11 was the hub gene. Overall, PIA promoted BMSCs proliferation and migration in the early stage of fracture healing, which was closely related to the fracture site tissue exosomes. Akt1, Actb and Uba52 were the hub mRNAs in the exosomes. Besides, Kif11 might be the key gene in BMSC regulated by tissue-derived exosomes of PIA treated rats.

Effect of Topical Tranexamic Acid on Seroma Formation in a Rat Mastectomy Model

BACKGROUND

Seroma is the most common complication after mastectomy and reconstruction surgery. Therefore, this study aimed to determine whether the topical application of tranexamic acid would be useful to reduce seromas in a rat mastectomy model.

METHODS

Forty-eight Sprague-Dawley rats were divided into four groups. After mastectomy and axillary lymph node dissection, 0.4 mL of normal saline was administered to group A in the dead space. In group B, 0.4 mL of a triamcinolone mixed solution was administered. In group C, 0.4 mL of a tranexamic acid (10 mg/kg) mixed solution was administered. In group D, 0.4 mL of a tranexamic acid (50 mg/kg) mixed solution was administered. Gross examination, assessment with micro-computed tomography (CT), quantitative analysis via aspiration, and histopathologic assessment were implemented 7 and 14 days postoperatively.

RESULTS

No other complications such as wound infection and skin necrosis were observed. At postoperative week 1, groups B and C showed significantly lower seroma volume values on micro-CT (P < 0.001 and P < 0.05, respectively) and seroma volume values at aspiration (P < 0.01 and P < 0.001, respectively) than group A. According to histopathologic analysis, inflammation was observed more frequently in groups A and D than in the other groups, and angiogenesis was more active in groups B and C than in the other groups.

CONCLUSIONS

Topical application of tranexamic acid was as effective as topical application of triamcinolone to prevent seroma formation. The stability of tranexamic acid was confirmed when the high dose of tranexamic acid was used.

NO LEVEL ASSIGNED

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High Fluoride Ingestion Impairs Bone Fracture Healing by Attenuating M2 Macrophage Differentiation

Fluorosis is still endemic in at least 25 countries around the world. In this study, we investigated the effect of high fluoride intake on fracture healing. Our in vitro experiments found that fluoride inhibited the osteogenic and angiogenic differentiation of MSCs in a dose-dependent manner. By constructing a bone fracture model, we found that high fluoride intake influences bone fracture by attenuating endochondral ossification and angiogenesis. In the mechanism, we clarified that high fluoride inhibits M2 differentiation rather than M1 differentiation in the fracture area, which may contribute to the delayed healing of the fracture. These findings provide an essential reference for the clinical treatment of bone fracture patients with a history of high fluoride intake or skeletal fluorosis patients.

Utilization of Tranexamic Acid in Surgical Orthopaedic Practice: Indications and Current Considerations

Tranexamic acid (TXA) is a lysine analog that exhibits an anti-fibrinolytic effect by directly preventing the activation of plasminogen as well as inhibiting activated plasmin from degrading fibrin clots, thereby promoting hemostasis and reducing the duration and quantity of blood loss. The aims of this study were to summarize the indications, routes of administration, safety, and clinical outcomes of TXA use throughout the different subspecialities in orthopedic surgery. Given that orthopedic procedures such as TKA, THA, fracture fixation, and various spine surgeries involve significant intraoperative blood loss, TXA is indicated in providing effective perioperative hemostasis. Additionally, use of TXA in orthopedic trauma has been indicated as a measure to reduce blood loss especially in a group with potential for hemodynamic compromise. TXA has been implicated in reducing the risk of blood transfusions in orthopedic trauma, joint surgery, and spine surgery, although this effect is not seen as prominently in sports medicine procedures. There remains disagreement in literature as to whether TXA via any route of administration can improve other clinically significant outcomes such as hospital length of stay and total operative time. Procedures that rely extensively on clarity on visualization of the surgical field such as knee and shoulder arthroscopies can greatly benefit from the use of TXA, thereby leading to less intraoperative bleeding, with better visual clarity of the surgical field. While most studies agree thrombosis due to TXA is unlikely, new research in cells and animal models are evaluating whether TXA can negatively impact other aspects of musculoskeletal physiology, however with conflicting results thus far. As of now, TXA remains a safe and effective means of promoting hemostasis and reducing intraoperative blood loss in orthopedic surgery.

The Efficacy and Safety of Tranexamic Acid Treatment in Orthopaedic Trauma Surgery

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Tranexamic acid (TXA) is a drug used to control hemorrhage by preventing the breakdown of fibrin.

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TXA is a cost-effective treatment for trauma patients across a variety of economic settings.

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Concerns of TXA causing thromboembolic events (TEEs) in orthopaedic trauma patients are not supported by evidence.

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TXA has been shown to reduce blood loss in hip fracture surgery.