The effect of topical and systemic tranexamic acid on fracture healing in rats

Effects of Tranexamic Acid on Human Osteoblasts as Proxy for Fracture Healing

OBJECTIVES

To investigate the effect of tranexamic acid (TXA) through in vitro culture of primary human osteoblasts (HOB) and in vivo using an operative rat femur fracture model. It was hypothesized that there would not be any effect on fracture healing in both studies.

METHODS

Primary HOBs were exposed to varying concentrations of TXA over different time periods. Cells were assessed for viability, metabolism, and mineralization. For the in vivo model, fractures were created in the femora of adult rats, exposed to either TXA or saline, and then assessed for healing at different time points. A modified radiographic union score for tibia was used to evaluate radiographs, callus mineralization was assessed with microcomputed tomography, and biomechanical tests were performed.

RESULTS

Overall, HOB viability and metabolism decreased as TXA concentration and exposure time increased. However, at concentrations below 56.44 mg/mL, HOB viability was not affected. Similarly, mineralization also decreased as TXA concentration and exposure time increased. In both groups, in vivo results demonstrated increasing radiographic healing, callus mineralization, and biomechanical strength as a function of time. There was a trend for increased healing in the TXA group at 6 weeks after fracture; however, the difference compared with untreated animals was not statistically significant.

CONCLUSIONS

Although a degradation of HOB viability and metabolism occurred with increased TXA concentrations and exposure times, clinically relevant concentrations do not adversely affect HOB viability, metabolism, or mineralization. In addition, there were no noticeable adverse effects of TXA administration in the in vivo model.

The effects of tranexamic acid on the histopathology of defect healing in an in vivo porcine model after gastric and colonic endoscopic submucosal dissection

Introduction

There is limited data on the histopathological effects of hemostatic agents (HAs) used during endoscopic submucosal dissection (ESD). We used an in vivo porcine model to compare the tissue effects of tranexamic acid (TXA) and adrenaline (epinephrine) compared to controls.

Methods

Standard ESD, using a 2 mm flash-knife, was performed in three pigs. Four resections were performed in the stomach and rectum of each pig. Injectate contained 4% succinylated gelatin solution and indigo carmine, plus either TXA, adrenaline, or neither. Pigs were euthanized after 7 days and evaluated by two blinded pathologists.

Results

Twenty-four defects were analyzed. Within each animal no significant histopathological changes were noted between the defects, but differences were noted between the animals. In the stomachs of the TXA and adrenaline pigs, pathology revealed a clear ulcer in the mucosa/submucosa with abundant granulation tissue, while the muscular layer was unaffected. In the control pig's stomach, the lesions were deeper, transmurally distributed, with inflammation of the muscular and adventitia layers accompanied by severe inflammation and necrosis. Fewer differences were noted in the rectum.

Conclusion

For ESD, HAs such as TXA and adrenaline may have protective effects on the depth and extent of injury to the underlying tissue.

Tranexamic Acid Can Reduce Early Tendon Adhesions After Rotator Cuff Repair and Is Not Detrimental to Tendon-Bone Healing: A Comparative Animal Model Study

PURPOSE

To determine the effects of topical tranexamic acid (TXA) administration on tendon adhesions, shoulder range of motion (ROM), and tendon healing in an acute rotator cuff repair rat model.

METHODS

A total of 20 Sprague Dawley rats were used. Tendon adhesion, ROM, and biomechanical and histological analysis of tendon-bone healing was conducted at 3 and 6 weeks after surgery. The rats underwent rotator cuff repair surgery on both shoulders and were administered TXA via subacromial injections. The tendon adhesion was evaluated macroscopically and histologically. Biomechanical tendon healing was measured using a universal testing machine, and histological analysis was quantified by H&E, Masson's trichrome, and picrosirius red staining.

RESULTS

At 3 weeks after surgery, the adhesion score was significantly lower in the TXA group (2.10 ± 0.32) than in the control group (2.70 ± 0.48) (P = .005), but there was no significant difference between the 2 groups at 6 weeks. Regarding ROM, compared with the control group, the TXA group showed significantly higher external rotation (36.35° ± 4.52° vs 28.42° ± 4.66°, P < .001) and internal rotation (45.35° ± 9.36° vs 38.94° ± 5.23°, P = .013) 3 weeks after surgery. However, at 6 weeks, there were no significant differences in external and internal rotation between the 2 groups. In the biomechanical analysis, no significant differences in gross examination (3 weeks, P = .175, 6 weeks, P = .295), load to failure (3 weeks, P = .117, 6 weeks, P = .295), or ultimate stress (3 weeks, P = .602, 6 weeks, P = .917) were noted between the 2 groups 3 and 6 weeks after surgery. In the histological analysis of tendon healing, no significant differences in the total score (3 weeks, P = .323, 6 weeks, P = .572) were found between the 2 groups 3 and 6 weeks after surgery.

CONCLUSIONS

Topical TXA administration showed a beneficial effect in reducing tendon adhesions and improving ROM 3 weeks postoperatively and had no effect at 6 weeks. This suggests that additional intervention with TXA may be useful in achieving long-term improvement in shoulder stiffness. Additionally, TXA may increase tissue ground substance accumulation in the late postoperative period but does not adversely affect tendon-bone interface healing.

CLINICAL RELEVANCE

The use of TXA after rotator cuff repair has no effect on tendon-bone interface healing in clinical practice and can improve shoulder stiffness in the early postoperative period. Additional research on the long-term effects is needed.

The emerging role of tranexamic acid and its principal target, plasminogen, in skeletal health

The worldwide burden of skeletal diseases such as osteoporosis, degenerative joint disease and impaired fracture healing is steadily increasing. Tranexamic acid (TXA), a plasminogen inhibitor and anti-fibrinolytic agent, is used to reduce bleeding with high effectiveness and safety in major surgical procedures. With its widespread clinical application, the effects of TXA beyond anti-fibrinolysis have been noticed and prompted renewed interest in its use. Some clinical trials have characterized the effects of TXA on reducing postoperative infection rates and regulating immune responses in patients undergoing surgery. Also, several animal studies suggest potential therapeutic effects of TXA on skeletal diseases such as osteoporosis and fracture healing. Although a direct effect of TXA on the differentiation and function of bone cells in vitro was shown, few mechanisms of action have been reported. Here, we summarize recent findings of the effects of TXA on skeletal diseases and discuss the underlying plasminogen-dependent and -independent mechanisms related to bone metabolism and the immune response. We furthermore discuss potential novel indications for TXA application as a treatment strategy for skeletal diseases.

The Effect of Topical Tranexamic Acid on Postrhinoplasty Periorbital Ecchymosis and Eyelid Edema

BACKGROUND

This study aimed to examine the effectiveness of topical tranexamic acid application in overcoming periorbital ecchymosis and eyelid edema in patients who have undergone open-technique rhinoplasty.

METHODS

Fifty patients were included in the study and divided into two groups: those who had topical tranexamic acid applied and those who did not (controls). In the tranexamic acid group, tranexamic acid-soaked pledgets were placed under the skin flap in a way that both sides could reach the osteotomy area and left for 5 minutes. In the control group, isotonic saline-soaked pledgets were placed under the skin flap in the same manner and left for 5 minutes. Digital photographs were obtained on postoperative days 1, 3, and 7. Eyelid edema and periorbital ecchymosis were scored by two different examiners and averaged for comparison.

RESULTS

Edema that developed in the patients who had tranexamic acid applied was significantly less than in the control group on postoperative day 1. There was no difference between the two groups on postoperative day 3 or 7. Ecchymosis that developed in patients who had tranexamic acid applied was significantly less than in the control group on all days.

CONCLUSIONS

Topical tranexamic acid applied to the surgical field immediately after osteotomy in rhinoplasty surgery reduces the development of postoperative periorbital ecchymosis. In addition, the topical tranexamic acid application also reduces the development of eyelid edema in the early postoperative period.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Tranexamic acid administered intraarticularly to the knee is safer for the articular cartilage and anterior cruciate ligament compared to intravenous administration: Histological analysis of an experimental rat model

In this study, the effects of tranexamic acid (TXA) on the knee's articular cartilage, anterior cruciate ligament (ACL), and joint capsule were assessed histologically. There were 15 rats in each of the 3 groups, totaling 45 rats. Intraarticular (IA) saline injections were applied for the first group, IA TXA injections for the second group, and intravenous (IV) TXA injections for the third group. Using samples taken from the knee joint 3 weeks later, the medial/lateral femoral condyle and medial/lateral tibial plateau articular cartilages were evaluated with Osteoarthritis Research Society International (OARSI) scoring, while ACL diameter and joint capsule thickness were analyzed histologically. In comparisons of OARSI scores for the medial/lateral femoral condyle and medial/lateral tibial plateau cartilage regions, the scores obtained for the IV TXA group were significantly higher than those of the IA saline group (P < 0.001, P = 0.001, P = 0.003, P = 0.011). In comparisons of medial/lateral femoral condyle and medial/lateral tibial plateau OARSI scores, the scores obtained for the IV TXA group were again significantly higher than those of the IA TXA group (P < 0.001, P < 0.001, P < 0.001, P = 0.002). When ACL diameters were compared, a significant decrease was observed in the ACL diameters of the IV TXA group compared to the IA saline and IA TXA groups (P < 0.001, P = 0.039). Histologically, IV TXA damages the articular cartilage and ACL more than IA TXA. IA administration of TXA is more protective when the articular cartilage and ACL are preserved.

Effects of repeated intravenous doses of tranexamic acid on closed tibial fracture healing: Experimental study based on the rat model

OBJECTIVE

The aim of this study was to assess the effects of tranexamic acid on fracture healing in the rat tibia closed fracture model.

METHODS

Sixty-four male Sprague-Dawley rats were included in this study, where closed fracture and intramedullary nailing were performed on their right tibial diaphyses. They were divided into 2 main groups, the experimental group, which was given weekly tranexamic acid injections, and the control group, which received no additional treatment. Eight rats from each group were sacrificed and evaluated for fracture healing at the first experimental group and control group, second experimental group and control group, third experimental group and control group, and fourth experimental group and control group weeks. Fracture healing was radiologically assessed according to the "Spencer Index" and "Lane and Sandhu Scoring System," and histologically evaluated according to the scoring system devised by Huo et al. Results: According to the Spencer Index, the mean union score was statistically significantly higher in the E3 group than in the third con- trol group (P = .014). Furthermore, the mean union score was statistically significantly higher in the fourth experimental group compared to the fourth control group (P=.047). According to the Lane and Sandhu Scoring System, only the mean union scores of the E3-4 groups were statistically significantly higher than the mean union scores of the C3-4 groups (P=.048). There was no histological difference between groups in terms of union, according to the criteria defined by Huo et al (P > .05).

CONCLUSION

This study showed us that repeated intravenous administrations of tranexamic acid had no negative effect on fracture heal- ing in the rat tibia fracture model. Although tranexamic acid demonstrated better radiological healing in the late period, it had no effect on histological union.

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

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Effect of Local Tranexamic Acid on the Quality of Bone Healing in a Rat Spinal Fusion Model

Introduction

The use of the antifibrinolytic agent tranexamic acid has positive effects on bleeding control, but our knowledge is still limited regarding how fibrinolysis suppression changes the process of bone formation and the quality of bone. Because of the several side effects of systemic tranexamic acid, topical usage has been established in several procedures. This study aimed to investigate the effect of local tranexamic acid on vertebral fusion by using macroscopic, radiologic, and microscopic techniques. We also attempted to determine the safe dose range in case some doses had negative effects on fusion.

Methods

Twenty-eight Wistar albino rats underwent intertransverse fusion. All rats were randomized into four groups: groups treated with local tranexamic acid doses of 1 mg/kg (D1), 10 mg/kg (D10), and 100 mg/kg (D100) and the control group with no drug (D0). At the end of the eighth week, all rats were sacrificed for evaluation in terms of palpation, mammography, and histopathologic analysis.

Results

The manual palpation results presented with lower fusion rates in D10 and D100 groups than in the control group. Radiological examination results were significantly higher in the control group. The histopathologic examination revealed no significant differences between groups in the percent of new bone formation.

Conclusions

Our results showed that local administration of tranexamic acid reduced the quality and stability of fusion without a delay in bone formation. However, doses of 1 mg/kg did not reduce the stability in the palpation test. Our findings suggest that 1 mg/kg dose is a critical threshold above which tranexamic acid reduced the bone healing process of fusion and that surgeons should consider the doses of local tranexamic acid during surgery.

Safety and Efficacy of Local Tranexamic Acid for the Prevention of Surgical Bleeding in Soft-Tissue Surgery: A Review of the Literature and Recommendations for Plastic Surgery

BACKGROUND

Although high-bleed surgery routinely utilizes the antifibrinolytic drug tranexamic acid, most plastic surgical procedures are conducted in soft tissue with low-volume bleeding. Unease regarding possible systemic adverse effects prevents widespread systemic use, but local use of tranexamic acid is gaining popularity among plastic surgeons. Randomized controlled trials on topical use of tranexamic acid are mainly from high-bleed surgeries, and few studies address the effect in soft tissue. This article reviews the scientific evidence regarding local use of tranexamic acid in soft-tissue surgery, discusses pharmacological effects and possible adverse reactions, and presents recommendations for use in plastic surgery.

METHODS

A systematic search of databases for studies on local use of tranexamic acid in soft-tissue surgery was performed. Randomized controlled trials were included for a systematic review on effect; a narrative review regarding other clinically relevant aspects is based on extensive literature searches combined with the authors' own research.

RESULTS

Fourteen randomized controlled trials, including 1923 patients, were included in the systematic review on local use of tranexamic acid in soft-tissue surgery.

CONCLUSIONS

Local use of tranexamic acid may reduce blood loss comparably to intravenous prophylactic use with negligible risk of systemic adverse effects, but high-quality randomized controlled trials are few. Prolonged exposure to high local concentrations is discouraged, and direct contact with the central nervous system may cause seizures. No single superior means of administration or dosage is supported in the literature, and lowest effective dose is unknown. There may not be one single ideal dosing regimen, but rather many possibilities adaptable for different surgical situations.

EFFECT OF TRANEXAMIC ACID ON FRACTURE HEALING IN RATS

Introduction

In this study we investigated the effect of tranexamic acid (TXA) on fracture healing in an established animal model, when used to stop bleeding in orthopedic trauma surgery.

Materials and Methods

This study was a randomized, controlled, laboratory study. Eighteen Sprague-Dawley rats were randomly assigned to three groups, either receiving TXA intravenously (Group 1), TXA topically (Group 2), or isotonic TXA intravenously and TXA topically in the same amounts for the control group (Group 3). First, a Kirschner wire was inserted retrogradely into the femoral intramedullary canal. Then the femurs were fractured at the midshaft region with blunt guillotine. After 4 weeks, the rats were sacrified and the femurs harvested. Cortical bone volume, callus volume, and bone mineral density were calculated using computer tomography scans. Torsion tests were performed. Groups were compared by maximum torque to failure and callus stiffness.

Results

There were no statistical differences in torque to failure and stiffness between the 3 groups. There were no differences in mean total bone volume, callus volume, percent bone volume, or callus density between the groups.

Conclusions

A single dose of topical or intravenous TXA has no negative effect on fracture healing when used in traumatic femur fracture surgery in an animal model. Evidence level II; Randomized controlled experimental study.

The histological effect of tranexamic acid on tendon-to-bone healing histologically in rats

Objectives

In this study, we aimed to investigate the effect of tranexamic acid (TXA) on osteotendinous junction healing in a rat model, both biomechanically and histologically.

Materials and methods

Sixty-four male Wistar-Albino rats weighing 450 to 600 g were used in this study. The rats were divided into two groups as the experimental (n=16) and control (n=16) groups. Achillotomy and subsequent repair site was exposed to 1 mL of TXA in the experimental group, while 1 mL of saline was given to the control group. For biomechanical and histopathological investigation, each group was further divided into two subgroups. At the end of four weeks, all rats were sacrificed. Biomechanical tests were performed using the M500-50CT device. The Bonar, Movin, and Nourissat bone-tendon junction scoring systems were used for histopathological evaluation.

Results

There was no statistically significant difference in the elongation at a maximum point, maximum loading, and maximum stress variables in the biomechanical study (p=0.558 p=0.775, and p=0.558, respectively). In the histopathological evaluation, the collagen content and layout were close to the native tissue in the experimental group (p=0.047 and p=0.008, respectively). Vascularity, hyalinization, and glycosaminoglycan content were significantly lower in the experimental group (p=0.004, p=0.014, and p=0.026, respectively). The total Bonar and Movin scores were more favorable in the experimental group (p<0.001).

Conclusion

This experimental study showed that local administration of TXA accelerated bone-tendon junction healing in rats.

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.

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

BACKGROUND

Tranexamic acid (TXA) is an antifibrinolytic agent. It has long been used to reduce the need for perioperative blood loss in various surgeries. Few studies have investigated the effects of local and intravenous administration of TXA on fracture healing. Thus, we aimed to evaluate if TXA influences hematoma volume and fracture healing in the rat tibia fracture model.

MATERIALS AND METHODS

A tibia fracture with intramedullary Kirschner wire fixation was created in all animals. Rats were randomly divided into three groups as local TXA, intravenous TXA, and control. A dose of 50 mg/kg local and intravenous TXA was administered to the study groups. Hematoma volume was measured on the first and third days of the study. The animals were sacrificed on the 14th and 21st days for radiological and histopathological examinations.

RESULTS

There was no significant difference between the groups in terms of hematoma volume measured on Day 1 and the mean decrease of hematoma volume from Day 1 to Day 3 (p = 0.158 and p = 0.239, respectively). The total radiological scores of Day 14 and Day 21 were similar in all groups (p > 0.05 for all). There was also no significant difference between the histological staging of the fracture repair on Day 14 and Day 21 for all groups (p > 0.05 for all).

CONCLUSION

Our findings suggest that TXA's local and intravenous application makes no significant difference in fracture healing.