这项工作是由NIAMS以R01-AR053645。

所有的程序批准由加州大学旧金山分校的机构动物照顾及使用委员会，并符合国家准则。 1。手术前准备的固定器<ol><li>前创造稳定骨折，需要装配的定制设计的外固定器。定制设计的外固定帧由两个铝环由三个不锈钢钢＃0/56螺纹棒，六角螺母8＃2/56，17（一小部分公司，佛罗里达州迈阿密湖3）匹配的螺栓稳定。 </li><li>每骨折，需要两个铝环。一环组装六角螺母4＃2/56（一小部分公司，佛罗里达州迈阿密湖）及配套螺栓到合适的孔，这些应保持宽松。这将是近端环。到远端环3螺母和螺栓组装，再不要完全拧紧。 </li></ol> 2。麻醉，骨折的创作，并固定器的应用<ol><li>小鼠（年龄，性别，身体重量由用户确定）50mg/ml氯胺酮，0.5腹腔注射麻醉毫克/:毫升Medetomidine（0.03毫升/鼠标）。 </li><li>申请到老鼠的眼睛和眼部润滑剂的磁带放置在其头的一块，在手术过程中保护自己的眼睛。 </li><li>动物被放置在一个程序的其余部分的加热垫。 </li><li> TRANSFIX使用4个0.25毫米的昆虫不育引脚（Anticorro:精细的科学工具，福斯特城，加利福尼亚州）的左胫骨近端和远端干骺端通过附加引脚到德雷梅尔工具，并通过骨钻。 </li><li>引脚是面向胫骨长轴垂直，90°对方。至少有10毫米之间的近端和远端引脚。 </li><li>定位高于近端向内坚果向着引脚，引脚的第一环。确保引脚保持集中在铝圈定位胫骨环。 </li><li>定位低于DI第二环STAL引脚和固定销使用前六角螺母环。第四螺母螺栓组合加入远端固定。 </li><li>三点弯曲与适当的设备，建立横向骨折。我们使用的Bonnarens和艾因霍恩4的重力系统。休息跨块胫骨外侧表面，提高体重下拉臂沿预定的高度和下降的重量，使接触产生钝骨折的胫骨外侧方面。身高体重从需求下降，每个小鼠品系，以确保一个单一的胫骨骨折专门决定。 </li><li>骨折，证实了X射线。 </li><li>确认骨折后，3个不锈钢＃0/56螺纹杆连接环。从远端开始插入杆和螺纹拖到远端环螺母固定杆。然后把另一个螺母上杆，将坐在这n上的近端环UT。确保两环，将举行相等的距离，不使劲的针脚。近端环获得第三螺母棒。 </li><li>丁丙诺啡（1.0毫克/千克）皮下注射镇痛手术后立即给予和动物疼痛和丁丙诺啡监测。 </li><li>麻醉逆转阿替美唑管理，动物进行监测，直到他们响应和走动。 </li></ol> 3。牵张成骨（另见:12,13） 修改这个程序，以适应牵张很简单。正在举行的环螺纹杆的位置，并把坚果棒戒指除了可以移动。 <ol><li>延迟:对于标准分心，利用该模型骨外固定器放置到胫骨，独自离开了5天的潜伏期。 </li><li>牵引:牵引osteog香根草可以进行转向稳定棒¼圈（0.25毫米）每天7天的坚果。 </li><li>成熟:骨桥观察10天，全面巩固牵引完成后27天观察。 </li></ol> 4。创作的临界尺寸缺陷创建一个关键尺寸的缺陷外固定器适用于以下修改与先前描述。 <ol><li>程序开始之前，皮肤用70％乙醇清洗。 </li><li>固定器是完全应用之前创建缺陷。 </li><li>然后将鼠标放置在解剖显微镜下可视化胫骨内侧，与10＃刀片手术刀切口（5-7毫米）。 </li><li>肌肉轻轻地切断和分离暴露中旬胫骨骨干。 </li><li>一个3毫米的骨段，然后从中期骨干用剪刀。使用T他指出剪刀，骨慢慢剪断，如有必要，镊子取出碎骨。应小心用剪刀的技巧，以避免胫骨取代大型机械力量。 </li><li>手术部位的检查，以确保有没有碎骨，因为这可以促进愈合。 </li><li>更换胫骨迟钝完周围的肌肉。 </li><li>在皮肤上，用2-3 6-0多胺​​单丝缝合关闭切口。 </li><li>逆转麻醉和监测动物疼痛，如前所述止痛。 </li></ol> 5。代表结果如果运用得当，减少（ 图1，2）具有优良的封闭性胫骨骨折外固定器提供更多的刚性稳定。然而，在某些情况下的不足，减少（发生明显和较大的差距之间的骨端或多处骨折（ 图3 </strong&gt;），并分析这些小鼠被排除。骨折稳定，使用这种方法主要是通过膜内骨化愈合（ 图4）。相反，如果没有稳定骨折大型软骨痂形成骨折间隙（ 图5），这是由骨取代通过膜内骨化过程。 <img alt="图1" src="/files/ftp_upload/3552/3552fig1.jpg" /> 图1说明用于稳定胫骨骨折外固定器的X光片。拍摄X光片后，呈现出良好的对齐骨段（箭头）骨折。 <img alt="图2" src="/files/ftp_upload/3552/3552fig2.jpg" /> 图2。已应用于后的固定鼠标的图像。 <img alt="图3" src="/files/ftp_upload/3552/3552fig3.jpg" /> 图3。X光片后出现Fracture显示对齐和分散的骨段（箭头）。 <img alt="图4" src="/files/ftp_upload/3552/3552fig4.jpg" /> 图4。通过膜内骨化稳定骨折愈合。稳定骨折的三色染色显示了一些新骨骨折部位（B）。比例尺= 500微米。 <img alt="图5" src="/files/ftp_upload/3552/3552fig5.jpg" /> 图5。非稳定骨折愈合通过软骨内骨化。 （b）在骨折部位的非稳定断裂的三色染色显示软骨（c）和骨。比例尺= 500微米。

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我们什么都没有透露。

两种不同的方式取决于机械稳定性（综述:14）骨头愈合。当留在不稳定的一个大型软骨模板形式取代骨骨折的差距，以弥合断骨两端。近端和远端断裂，骨内，骨膜及骨内膜的膜内骨化形成直接的。相比之下，发生在稳定骨折愈合完全通过膜内骨化3。然而，这两个进程之间的开关调节的具体机制不明。有证据表明，机械环境中的干细胞的命运是基因控制，并可以改变。在小鼠体?...

<table border="1"><tbody><tr><td> 试剂名称 </td><td> 公司 </td><td> 目录编号 </td><td> 评论 </td></tr><tr><td> 0.25毫米昆虫针</td><td>精细科学工具</td><td> 26000-25 </td><td>涂黑阳极氧化钢，0.25毫米杆直径，4厘米的长度</td></tr><tr><td>不锈钢六角螺母</td><td>小零件</td><td> ＃2-56 </td><td> 1/8"的长度，每英寸56线程</td></tr><tr><td>不锈钢六角螺母</td><td>小零件</td><td> ＃0-80 </td><td> 1/8"的长度，每英寸80线程</td></tr><tr><td>不锈钢机螺钉</td><td>小零件</td><td> ＃0-80 </td><td> 1/8"的长度，每英寸80线程</td></tr><tr><td>不锈钢机剪切螺杆</td><td>小零件</td><td> ＃0-80 </td><td> 6"的长度，每英寸80线程</td></tr><tr><td> 18-8不锈钢头机SCREW </td><td>麦克马斯特，卡尔</td><td></td><td> 2-56主题，3/6"的长度</td></tr><tr><td>外固定器</td><td>车间</td><td>定制设计</td><td></td></tr></tbody></table>

creating rigidly stabilized fractures for assessing intramembranous ossification, distraction osteogenesis, or healing of critical sized defects

评估骨骼修复的模式是用于开发用于临床治疗骨折的治疗至关重要。机械稳定性骨损伤愈合中起着很大的作用。在最坏的情况下，机械不稳定，可能导致延迟或在非工会的人。然而，运动还可以促进愈合过程。在骨折有运动软骨组织形式，以稳定骨折的骨端，骨和软骨逐渐取代通过软骨内骨化发育过程的概括。相反，如果骨折稳定硬性骨形成直接通过膜内骨化。临床上，同时出现软骨内和膜内骨化。为了有效地复制这个过程中研究者一根针插入髓腔的断骨Bonnarens 4的 。这种实验方法提供了极好的横向稳定性，同时允许rotatio坚持信号不稳定。然而，我们理解的机制，规范这两个不同的过程，也可以加强实验隔离这些进程。我们已经开发出一种稳定的协议，提供旋转和横向稳定。在这种模式下，膜内骨化是唯一的模式，观察愈合，愈合的参数，可以在不同品系的转基因小鼠5-7后，8,9生物活性分子的应用，改变生理参数的愈合10后，比较，修改后牵张12后的金额或11稳定时间，创 ​​造一个非工会13后，或之后创建一个关键尺寸的缺陷。在这里，我们说明如何申请学习和小鼠胫骨骨折愈合牵张改良Ilizarov外固定器。

Watch this Scientific Journal Video about Creating Rigidly Stabilized Fractures for Assessing Intramembranous Ossification, Distraction Osteogenesis, or Healing of Critical Sized Defects at JoVE.com

Creating Rigidly Stabilized Fractures for Assessing Intramembranous Ossification, Distraction Osteogenesis, or Healing of Critical Sized Defects

本文介绍了一种稳定的长骨骨折的方法是基于改良Ilizarov外固定器的应用<sup&gt; 1-3</sup&gt;。固定架和创造的骨损伤的应用后，可以评估愈合，牵张可以被执行，或者可以创建和非工会或大小的关键缺陷，用于研究治疗干预。

建立评估膜内骨化硬性稳定骨折，牵张成骨，或临界中小企业缺损愈合

Assessing modes of skeletal repair is essential for developing therapies to be used clinically to treat fractures. Mechanical stability plays a large role ...

creating-rigidly-stabilized-fractures-for-assessing-intramembranous

Universidad de Cartagena UDEC

Research

JoVE Journal

Medicine

17.3K 次观看.  University of California, San Francisco. 本文介绍了一种稳定的长骨骨折的方法是基于改良Ilizarov外固定器的应用 1-3。固定架和创造的骨损伤的应用后，可以评估愈合，牵张可以被执行，或者可以创建和非工会或大小的关键缺陷，用于研究治疗干预。

视频: Creating Rigidly Stabilized Fractures for Assessing Intramembranous Ossification, Distraction Osteogenesis, or Healing of Critical Sized Defects

Repair of a Critical-sized Calvarial Defect Model Using Adipose-derived Stromal Cells Harvested from Lipoaspirate

Craniofacial skeletal repair and regeneration offers the promise of de novo tissue formation through a cell-based approach utilizing stem cells. Adipose-derived stromal cells (ASCs) have proven to be an abundant source of multipotent stem cells capable of undergoing osteogenic, chondrogenic, adipogenic, and myogenic differentiation. Many studies have explored the osteogenic potential of these cells in vivo with the use of various scaffolding biomaterials for cellular delivery. It has been demonstrated that by utilizing an osteoconductive, hydroxyapatite-coated poly(lactic-co-glycolic acid) (HA-PLGA) scaffold seeded with ASCs, a critical-sized calvarial defect, a defect that is defined by its inability to undergo spontaneous healing over the lifetime of the animal, can be effectively show robust osseous regeneration. This in vivo model demonstrates the basis of translational approaches aimed to regenerate the bone tissue - the cellular component and biological matrix. This method serves as a model for the ultimate clinical application of a progenitor cell towards the repair of a specific tissue defect.

This protocol describes the isolation of adipose-derived stromal cells from lipoaspirate and the creation of a 4 mm critical-sized calvarial defect to evaluate skeletal regeneration.

修复的临界大小的颅骨缺损模型脂肪间充质干细胞的收获Lipoaspirate

Craniofacial skeletal repair and regeneration offers the promise of de novo tissue formation through a cell-based approach utilizing stem cells. ...

科研

医学

Murine Model of Wound Healing

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.

A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

伤口愈合的小鼠模型

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. ...

Assessing Changes in Volatile General Anesthetic Sensitivity of Mice after Local or Systemic Pharmacological Intervention

One desirable endpoint of general anesthesia is the state of unconsciousness, also known as hypnosis. Defining the hypnotic state in animals is less straightforward than it is in human patients. A widely used behavioral surrogate for hypnosis in rodents is the loss of righting reflex (LORR), or the point at which the animal no longer responds to their innate instinct to avoid the vulnerability of dorsal recumbency. We have developed a system to assess LORR in 24 mice simultaneously while carefully controlling for potential confounds, including temperature fluctuations and varying gas flows. These chambers permit reliable assessment of anesthetic sensitivity as measured by latency to return of the righting reflex (RORR) following a fixed anesthetic exposure. Alternatively, using stepwise increases (or decreases) in anesthetic concentration, the chambers also enable determination of a population's sensitivity to induction (or emergence) as measured by EC50 and Hill slope. Finally, the controlled environmental chambers described here can be adapted for a variety of alternative uses, including inhaled delivery of other drugs, toxicology studies, and simultaneous real-time monitoring of vital signs.

Loss of the righting reflex has long served as a standard behavioral surrogate for unconsciousness, also called hypnosis, in laboratory animals. Alterations in volatile anesthetic sensitivity caused by pharmacological interventions can be detected with a carefully controlled high-throughput assessment system, which may be adapted for delivery of any inhaled therapeutic.

局部或全身药物干预后评估的变化小鼠中挥发性全身麻醉药敏感性

One desirable endpoint of general anesthesia is  the state of unconsciousness, also known as hypnosis. Defining the hypnotic state in animals is  less ...

Minimally Invasive Thumb-sized Pterional Craniotomy for Surgical Clip Ligation of Unruptured Anterior Circulation Aneurysms

Less invasive surgical approaches for intracranial aneurysm clipping may reduce length of hospital stay, surgical morbidity, treatment cost, and improve patient outcomes. We present our experience with a minimally invasive pterional approach for anterior circulation aneurysms performed in a major tertiary cerebrovascular center and compare the results with an aged matched dataset from the Nationwide Inpatient Sample (NIS). From August 2008 to December 2012, 22 elective aneurysm clippings on patients &#8804;55 years of age were performed by the same dual fellowship-trained cerebrovascular/endovascular neurosurgeon. One patient (4.5%) experienced transient post-operative complications. 18 of 22 patients returned for follow-up imaging and there were no recurrences through an average duration of 22 months. A search in the NIS database from 2008 to 2010, also for patients aged &#8804;55 years of age, yielded 1,341 hospitalizations for surgical clip ligation of unruptured cerebral aneurysms. Inpatient length of stay and hospital charges at our institution using the minimally invasive thumb-sized pterional technique were nearly half that of NIS (length of stay: 3.2 vs 5.7 days; hospital charges: $52,779 vs. $101,882). The minimally invasive thumb-sized pterional craniotomy allows good exposure of unruptured small and medium-sized supraclinoid anterior circulation aneurysms. Cerebrospinal fluid drainage from key subarachnoid cisterns and constant bimanual microsurgical techniques avoid the need for retractors which can cause contusions, localized venous infarctions, and post-operative cerebral edema at the retractor sites. Utilizing this set of techniques has afforded our patients with a shorter hospital stay at a lower cost compared to the national average.

Minimally invasive thumb-sized pterional craniotomy for aneurysm clipping has afforded our patients with a shorter hospital stay at a lower cost compared to the national average.

微创拇指大小翼点入开颅未破裂前循环动脉瘤的手术夹子结扎

Less invasive surgical approaches for intracranial aneurysm clipping may reduce length of hospital stay, surgical morbidity, treatment cost, and improve ...

A Simple Critical-sized Femoral Defect Model in Mice

While bone has a remarkable capacity for regeneration, serious bone trauma often results in damage that does not properly heal. In fact, one tenth of all limb bone fractures fail to heal completely due to the extent of the trauma, disease, or age of the patient. Our ability to improve bone regenerative strategies is critically dependent on the ability to mimic serious bone trauma in test animals, but the generation and stabilization of large bone lesions is technically challenging. In most cases, serious long bone trauma is mimicked experimentally by establishing a defect that will not naturally heal. This is achieved by complete removal of a bone segment that is larger than 1.5 times the diameter of the bone cross-section. The bone is then stabilized with a metal implant to maintain proper orientation of the fracture edges and allow for mobility. 
Due to their small size and the fragility of their long bones, establishment of such lesions in mice are beyond the capabilities of most research groups. As such, long bone defect models are confined to rats and larger animals. Nevertheless, mice afford significant research advantages in that they can be genetically modified and bred as immune-compromised strains that do not reject human cells and tissue.
Herein, we demonstrate a technique that facilitates the generation of a segmental defect in mouse femora using standard laboratory and veterinary equipment. With practice, fabrication of the fixation device and surgical implantation is feasible for the majority of trained veterinarians and animal research personnel. Using example data, we also provide methodologies for the quantitative analysis of bone healing for the model.

Animal models are frequently employed to mimic serious bone injury in biomedical research. Due to their small size, establishment of stabilized bone lesions in mice are beyond the capabilities of most research groups. Herein, we describe a simple method for establishing and analyzing experimental femoral defects in mice.

一个简单的临界尺寸股骨缺损模型小鼠

While bone has a remarkable capacity for regeneration, serious bone trauma often results in damage that does not properly heal. In fact, one tenth of all ...

Direct Mouse Trauma/Burn Model of Heterotopic Ossification

Heterotopic ossification (HO) is the formation of bone outside of the skeleton which forms following major trauma, burn injuries, and orthopaedic surgical procedures. The majority of animal models used to study HO rely on the application of exogenous substances, such as bone morphogenetic protein (BMP), exogenous cell constructs, or genetic mutations in BMP signaling. While these models are useful they do not accurately reproduce the inflammatory states that cause the majority of cases of HO. Here we describe a burn/tenotomy model in mice that reliably produces focused HO. This protocol involves creating a 30% total body surface area partial thickness contact burn on the dorsal skin as well as division of the Achilles tendon at its midpoint. Relying solely on traumatic injury to induce HO at a predictable location allows for time-course study of endochondral heterotopic bone formation from intrinsic physiologic processes and environment only. This method could prove instrumental in understanding the inflammatory and osteogenic pathways involved in trauma-induced HO. Furthermore, because HO develops in a predictable location and time-course in this model, it allows for research to improve early imaging strategies and treatment modalities to prevent HO formation.

An Achilles tenotomy and burn injury model of heterotopic ossification allows for the reliable study of trauma induced ectopic bone formation without the application of exogenous factors.

异位骨化直接鼠标创伤/烧伤模型

Heterotopic ossification (HO) is the formation of bone outside of the skeleton which forms following major trauma, burn injuries, and orthopaedic surgical ...

Establishment of a Segmental Femoral Critical-size Defect Model in Mice Stabilized by Plate Osteosynthesis

The use of tissue-engineered bone constructs is an appealing strategy to overcome drawbacks of autografts for the treatment of massive bone defects. As a model organism, the mouse has already been widely used in bone-related research. Large diaphyseal bone defect models in mice, however, are sparse and often use bone fixation which fills the bone marrow cavity and does not provide optimal mechanical stability. The objectives of the current study were to develop a critical-size, segmental, femoral defect in nude mice. A 3.5-mm mid-diaphyseal femoral ostectomy (approximately 25% of the femur length) was performed using a dedicated jig, and was stabilized with an anterior located locking plate and 4 locking screws. The bone defect was subsequently either left empty or filled with a bone substitute (syngenic bone graft or coralline scaffold). Bone healing was monitored noninvasively using radiography and in vivo micro-computed-tomography and was subsequently assessed by ex vivo micro-computed-tomography and undecalcified histology after animal sacrifice, 10 weeks postoperatively. The recovery of all mice was excellent, a full-weight-bearing was observed within one day following the surgical procedure. Furthermore, stable bone fixation and consistent fixation of the implanted materials were achieved in all animals tested throughout the study. When the bone defects were left empty, non-union was consistently obtained. In contrast, when the bone defects were filled with syngenic bone grafts, bone union was always observed. When the bone defects were filled with coralline scaffolds, newly-formed bone was observed in the interface between bone resection edges and the scaffold, as well as within a short distance within the scaffold. 
The present model describes a reproducible critical-size femoral defect stabilized by plate osteosynthesis with low morbidity in mice. The new load-bearing segmental bone defect model could be useful for studying the underlying mechanisms in bone regeneration pertinent to orthopaedic applications.

Although mouse models are invaluable tools for bone tissue engineering, models of long bone defects are sparse. This need motivated development of the present protocol which uses a locking plate with four screws and a dedicated jig to perform and stabilize a reproducible, femoral, critical-size defect with low morbidity.

在小鼠节段性股临界尺寸缺陷模型的建立接骨板稳定

The use of tissue-engineered bone constructs is an appealing strategy to overcome drawbacks of autografts for the treatment of massive bone defects. As a ...

Scleral Cross-linking Using Riboflavin and Ultraviolet-A Radiation for Prevention of Axial Myopia in a Rabbit Model

Myopic individuals, especially those with severe myopia, are at higher-than-normal risk of cataract, glaucoma, retinal detachment and chorioretinal abnormalities. In addition, pathological myopia is a common irreversible cause of visual impairment and blindness1-3. Our study demonstrates the effect of scleral crosslinking using riboflavin and ultraviolet-A radiation on the development of axial myopia in a rabbit model. The axial length of the eyeball was measured by A-scan ultrasound in New Zealand white rabbits aged 13 days (male and female). The eye then underwent 360&#176; conjunctival peritomy with scleral crosslinking, followed by tarsorrhaphy. Axial elongation was induced in 13 day-old New Zealand rabbits by suturing their right eye eyelids (tarsorrhaphy). The eyes were divided into quadrants, and every quadrant had two scleral irradiation zones, each with an area of 0.2 cm&#178; and a radius of 4 mm. Crosslinking was performed by dropping 0.1% dextran-free riboflavin-5-phosphate onto the irradiation zones 20 sec before ultraviolet-A irradiation and every 20 sec during the 200 sec irradiation time. UVA radiation (370 nm) was applied perpendicular to the sclera at 57 mW/cm&#178; (total UVA light dose, 57 J/cm&#178;). Tarsorrhaphies were removed on day 55, followed by repeated axial length measurements. This study demonstrates that scleral crosslinking with riboflavin and ultraviolet-A radiation effectively prevents occlusion-induced axial elongation in a rabbit model.

We demonstrate the effect of scleral crosslinking with riboflavin and UVA on an axial elongation rabbit eye. Axial elongation was induced in 13 day-old New Zealand rabbits (male and female) by suturing their right eye eyelids (tarsorrhaphy).

巩膜交联兔模型使用核黄素和紫外辐射的轴性近视防治

Myopic individuals, especially those with severe myopia, are at higher-than-normal risk of cataract, glaucoma, retinal detachment and chorioretinal ...

The Generation of Closed Femoral Fractures in Mice: A Model to Study Bone Healing

Bone fractures impose a tremendous socio-economic burden on patients, in addition to significantly affecting their quality of life. Therapeutic strategies that promote efficient bone healing are non-existent and in high demand. Effective and reproducible animal models of fractures healing are needed to understand the complex biological processes associated with bone regeneration. Many animal models of fracture healing have been generated over the years; however, murine fracture models have recently emerged as powerful tools to study bone healing. A variety of open and closed models have been developed, but the closed femoral fracture model stands out as a simple method for generating rapid and reproducible results in a physiologically relevant manner. The goal of this surgical protocol is to generate unilateral closed femoral fractures in mice and facilitate a post-fracture stabilization of the femur by inserting an intramedullary steel rod. Although devices such as a nail or a screw offer greater axial and rotational stability, the use of an intramedullary rod provides a sufficient stabilization for consistent healing outcomes without producing new defects in the bone tissue or damaging nearby soft tissue. Radiographic imaging is used to monitor the progression of callus formation, bony union, and subsequent remodeling of the bony callus. Bone healing outcomes are typically associated with the strength of the healed bone and measured with torsional testing. Still, understanding the early cellular and molecular events associated with fracture repair is critical in the study of bone tissue regeneration. The closed femoral fracture model in mice with intramedullary fixation serves as an attractive platform to study bone fracture healing and evaluate therapeutic strategies to accelerate healing.

The murine closed femoral fracture model is a powerful platform to study fracture healing and novel therapeutic strategies to accelerate bone regeneration. The goal of this surgical protocol is to generate unilateral closed femoral fractures in mice using an intramedullary steel rod to stabilize the femur.

小鼠闭合性股骨骨折的形成: 骨愈合模型的研究

Bone fractures impose a tremendous socio-economic burden on patients, in addition to significantly affecting their quality of life. Therapeutic strategies ...

Fracture Apparatus Design and Protocol Optimization for Closed-stabilized Fractures in Rodents

The reliable generation of consistent stabilized fractures in animal models is essential for understanding the biology of bone regeneration and developing therapeutics and devices. However, available injury models are plagued by inconsistency resulting in wasted animals and resources and imperfect data. To address this problem of fracture heterogeneity, the purpose of the method described herein is to optimize fracture generation parameters specific to each animal and yield a consistent fracture location and pattern. This protocol accounts for variations in bone size and morphology that may exist between mouse strains and can be adapted to generate consistent fractures in other species, such as rat. Additionally, a cost-effective, adjustable fracture apparatus is described. Compared to current stabilized fracture techniques, the optimization protocol and new fracture apparatus demonstrate increased consistency in stabilized fracture patterns and locations. Using optimized parameters specific to the sample type, the described protocol increases the precision of induced traumas, minimizing the fracture heterogeneity typically observed in closed-fracture generation procedures.

The goal of the protocol is to optimize the fracture generation parameters to yield consistent fractures. This protocol accounts for the variations in bone size and morphology that may exist between animals. Additionally, a cost-effective, adjustable fracture apparatus is described.

鼠类闭合稳定骨折的断裂装置设计与协议优化

The reliable generation of consistent stabilized fractures in animal models is essential for understanding the biology of bone regeneration and developing ...