Name: Development of a Novel Internal Fixation Model for Rat Radial Fractures: Fracture Healing Assessment and Dorsal Root Ganglion Isolation (Video) | JoVE Journal
Uploaded: 2026-03-13T15:00:00.000+00:00
Duration: 11 min 21 s
Description: Learn a novel internal fixation method combining sutures and titanium needles for rat radial fractures. This protocol uses micro-CT imaging to assess bone healing and isolates dorsal root ganglion neurons to study nerve-bone repair mechanisms.

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5 minutes

This work was supported by grants from the Scientific research project of Jiangsu traditional Chinese medicine society (XYLD2024038) and, Scientific research project of Nantong Health and Wellness Committee (QNZ2023115).

All animal experiments were approved by the Animal Ethics Committee of Nanjing University of Chinese Medicine (No. 202508A046). All rats used in the following assays were maintained in specific pathogen-free (SPF) conditions. A schematic representing the protocol is shown in Figure 1.
1. Establishment of an internal fixation model for radial fractures in rats
NOTE: Rats were acclimated to a quiet environment with soft, diffused lighting prior to surgery, shielding them from noise and harsh illumination. During handling, the rats&#39; abdomen and chest were supported with gentle manual restraint, avoiding tail grasping, a practice known to induce pain and distress and to reduce discomfort associated with struggling.
<ol>
	<li>Prepare the surgical instruments as shown in Figure 2. The surgical instruments include a scalpel blade, a scalpel handle, operating scissors, a needle holder, hemostatic forceps, and toothed tissue forceps. The male Sprague-Dawley (SD) rat was approximately 8 weeks old and weighed about 200 g.</li>
	<li>Anesthetize the rat using an isoflurane gas anesthesia machine. For induction, use 4% isoflurane and maintain ventilatory anesthesia (2% isoflurane) using a nose cone throughout the surgical procedure. Maintain the operating room temperature at approximately 28 &#176;C. 
	NOTE: Determine the success of anesthesia by checking vital signs (such as respiration and heart rate), corneal reflex (no response indicates effective anesthesia), blink reflex (absence), and toe contraction response (no retraction after stimulation).</li>
	<li>Place the rat in the lateral position, expose the right forelimb, and shave off the hair using a hair clipper. Drape a sterile sheet and wrap a tourniquet around the proximal right forelimb to reduce surgical bleeding.</li>
	<li>Prepare the skin by alternating alcohol and betadine scrubs three times.</li>
	<li>Make a 1.5-cm longitudinal incision on the dorsal radial side of the right forearm, as shown in Figure 3. Separate the muscle spaces and fully expose the right forelimb radius. 
	NOTE: The radius is exposed by bluntly separating the muscles along the muscle interspace. Only the dorsal muscles of the radius are exposed without completely stripping the surrounding muscles.</li>
	<li>Use operating scissors to cut the radius to create a transverse fracture. The scissors are oriented at a 90-degree angle to the radius (Figure 4).</li>
	<li>Take a 0.8 mm-diameter, 10 mm-long titanium needle and insert it into the radius fracture along its longitudinal axis (Figure 5). Fix the radius and the titanium needle with suture (4-0 [1.5 metric] silk braided non-absorbable), as shown in Figure 6.</li>
	<li>Tie the suture with three consecutive knots, and secure the titanium needle to the radius via four interrupted sutures. 
	NOTE: The proximal and distal ends of the fracture are fixed twice, respectively.</li>
	<li>Suture (4-0 [1.5 metric] silk braided non-absorbable) the skin, cut off the excess suture, and close the wound. Disinfect the skin with Betadine scrubs.</li>
	<li>Cover the wound with sterile gauze and secure it with bandages. Place the rat in a cage to regain consciousness until recovery.</li>
	<li>Postoperative pain management:
	<ol>
		<li>If the animal demonstrates signs of pain, is not eating, and/or hesitates to walk on their hindlimbs, consult with veterinary personnel and administer additional analgesics. 
		NOTE: Cefuroxime sodium is used in the treatment of bacterial infections. Tramadol hydrochloride is used to administer analgesics.</li>
	</ol>
	</li>
</ol>
2. Micro CT imaging
<ol>
	<li>Anesthetize the rat using an isoflurane gas (induction dose 4%) anesthesia machine.</li>
	<li>Place the rat in a prone position within the scanning chamber, adjust limb and head positioning to center the target scanning area in the field of view, and maintain continuous ventilation and anesthesia (2% isoflurane) throughout the procedure.</li>
	<li>Push the fixed animal bed into the scanning chamber and close the chamber door.</li>
	<li>Set the micro-CT scanning parameters as follows. Scan mode: standard; exposure time: 2 min; field of view: 72 mm; voxel size: 144 &#181;m; voltage: 90 kV; current: 88 &#181;A; filter: 3D-soft. 
	NOTE: The scan data is automatically transmitted to the software, and a three-dimensional CT image is generated.</li>
	<li>Separate the target tissues.
	<ol>
		<li>Analyze the selected bone tissue area from the original micro-CT images. Slide the transfer function line to separate the bone from the muscle, avoiding too much muscle tissue included. Perform the high-resolution reconstruction on the segmented bone tissue area to generate a 3D model.</li>
	</ol>
	</li>
	<li>Export the processed images.
	<ol>
		<li>After processing the images, locate and click the end button to finalize the current workflow.</li>
		<li>A pop-up window will appear, first select still to confirm you want to export a static image (not a dynamic sequence).</li>
		<li>Choose jpeg as the output file format from the available options.</li>
		<li>Select large size to ensure the exported image retains high resolution suitable for analysis or documentation.</li>
		<li>Click OK to complete the export process.</li>
	</ol>
	</li>
</ol>
3. Isolation and culture of DRG in rats with radial fractures
NOTE: Euthanasia is administered with 4% isoflurane inhalation anesthesia, followed by rapid cervical dislocation to euthanize the animals. The DRGs are extracted 20 days after the radial fracture model establishment.
<ol>
	<li>Sever the spine, remove the C1-C7 vertebral bodies. Cut the cervical spine along the anterior and posterior midlines, and divide it into left and right halves. If necessary, cut off the spinous processes to facilitate the operation.</li>
	<li>Gently clean the spinal cord tissue and nerve fibers inside the intervertebral foramina. Rinse the intervertebral foramina with a syringe filled with PBS to remove the blood to expose the lateral recesses. 
	NOTE: The DRG is located inside the lateral recesses, presenting as a light-yellow nodule, with nerve fibers connected at both ends.</li>
	<li>Use toothed tissue forceps to pick up the DRG, gently lift it, and then use operating scissors to cut the nerve fibers at both ends.</li>
	<li>Transfer the extracted DRGs to a 1.5 mL centrifuge tube with extraction medium; place on ice. 
	NOTE: Prepare the extraction medium by adding 2% fetal bovine serum (FBS) to the &#945;-Minimum Essential Medium (&#945;-MEM). The DRGs are incubated in the extraction medium for about 30 min before proceeding to the next step.</li>
	<li>Slowly aspirate and discard the extraction medium. Add 1 mL of the mixed digestive enzyme working solution. Digest in a 37 &#176;C water bath for 60-70 min. 
	NOTE: To prepare the mixed digestive enzyme working solution, dissolve 100 mg of type I collagenase and 100 mg of dispase in 1 mL of Phosphate Buffered Saline (PBS). When using, dilute it to a working solution of 5 mg/mL and store it on ice.</li>
	<li>Coat a Petri dish by pipetting an appropriate volume of the fibronectin working solution, then incubate at 37 &#176;C for 1 h. 
	NOTE: Human plasma fibronectin working solution (Fibronectin working solution) is prepared by diluting the 1 mg/mL Fibronectin stock solution with ddH&#8322;O to a 0.02 mg/mL Fibronectin working solution.</li>
	<li>Post-digestion, aspirate and discard the mixed digestive enzyme working solution. Add 1 mL of complete medium, and gently pipette the DRG tissue several times. 
	NOTE: To prepare complete medium, mix 45 mL of MEM-&#945; medium, 4.5 mL of FBS, and 0.5 mL of Penicillin-Streptomycin (PS) solution, and sterilize by filtration through a 0.22 &#181;m sterilizing-grade microporous membrane.</li>
	<li>Collect filtrate, centrifuge at 75 &#215; g for 8.5 min at 25 &#176;C.</li>
	<li>After centrifugation, aspirate and discard the supernatant in the centrifuge tube, and add 1 mL of complete medium to resuspend the precipitate.</li>
	<li>Take out the Petri dish. Discard the Fibronectin working solution and wash with PBS twice.</li>
	<li>Inoculate the cells into the coated Petri dish, add 1 mL of complete medium, and incubate in a constant-temperature incubator at 37 &#176;C with 5% CO&#8322; for 8-12 h.</li>
	<li>After 8-12 h, replace the complete medium with replacement medium. Then, replace half of the volume with the replacement medium every 2-3 days. 
	NOTE: To prepare replacement medium, mix 44.5 mL of MEM-&#945; medium, 4.5 mL of FBS, 0.5 mL of Penicillin-Streptomycin (PS) solution, and 0.5 mL Deoxyuridine. Sterilize by filtration through a 0.22 &#181;m sterilizing-grade microporous membrane.</li>
</ol>

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</ol>

All the authors declare that they have no potential conflicts of interest.

Radial fracture is one of the most common long bone fractures in clinical practice. Its healing process involves complex interactions between bone tissue repair and neural regulation (such as the regulation of osteoblasts/osteoclasts by neuropeptides and neurotrophic factors released from the dorsal root ganglion)15,16,17,18. Rats are a classic model for studying the mechanism of fracture heali...

Radial fractures are among the most common clinical fractures, with a substantial global incidence, and rank as a leading cause of long-bone fractures in the extremities1,2,3. Population studies reveal a bimodal age distribution for radial fractures, typically peaking in both pediatric and elderly populations4. Delayed treatment often results in forearm rotational dysfunction, severely impairing activities of daily living (ADLs)5,6. Controversies persist in radial fracture management, primarily centered on fracture classification systems and treatment modality selection7,8. Clinical evidence suggests that open reduction internal fixation (ORIF) significantly improves elbow or wrist joint range of motion (ROM) and strength recovery9; however, this approach is associated with higher rates of postoperative infections and internal fixation-related complications10,11.
The DRG serves as a critical anatomical and functional bridge for sensory information transmission between the peripheral and central nervous systems (CNS). Beyond its primary role in collecting and relaying peripheral sensory signals (e.g., touch, temperature), the DRG actively regulates abnormal sensations such as pain, making it a key structure underlying both normal sensory function and clinical pain management12,13,14. Pathological changes such as injury, inflammation, or neurodegeneration in the DRG can trigger sensory abnormalities (e.g., numbness, tingling) or chronic pain, positioning it as a focal point of research in neuroscience and pain medicine.
Herein, the 8-week-old male SD rats weighing approximately 200 g were selected to construct (1) an internal fixation model for radial transverse fractures in rats and subsequent post-healing assessment, and (2) the isolation and in vitro culture of DRGs from rats with an internal fixation model for radial fractures. This protocol is designed to facilitate reproducible experimentation in studies exploring fracture healing mechanisms, DRG-mediated sensory changes, and potential therapeutic targets for post-fracture pain or dysfunction.

<table><tbody><tr><td>5-Fluoro-2&#039; deoxyuridine</td><td>sigma</td><td>F0503</td><td></td></tr><tr><td>Cefuroxime sodium&amp;nbsp;</td><td>Shandong Runze Pharmaceutical Co., Ltd., China</td><td>Guoyao Zhunzi H20205058</td><td></td></tr><tr><td>DAPI Staining Solution</td><td>Biyotime</td><td>C1005</td><td></td></tr><tr><td>Dispersase</td><td>Shanghai yuanye Bio-Technology Co., Ltd.</td><td>S25046</td><td></td></tr><tr><td>Fetal bovine serum (FBS)</td><td>Thermo</td><td>16000-044</td><td></td></tr><tr><td>hemostatic forceps&amp;nbsp;</td><td>Shanghai Medical Instrument (Group) Co.,Ltd.&amp;nbsp;</td><td>J31070</td><td></td></tr><tr><td>Human plasma fibronectin (Human Fibronectin)&amp;nbsp;</td><td>sigma</td><td>F0895</td><td></td></tr><tr><td>Isoflurane</td><td>RWD</td><td>R510-22-10&amp;nbsp;</td><td></td></tr><tr><td>Live animal micro-CT imaging system</td><td>PerkinElmer in the USA</td><td>Quantum GX&amp;nbsp;</td><td></td></tr><tr><td>MEM-ALPHA Culture medium&amp;nbsp;</td><td>BI</td><td>C3060</td><td></td></tr><tr><td>needle holder&amp;nbsp;</td><td>Shanghai Medical Instrument (Group) Co.,Ltd.&amp;nbsp;</td><td>200622</td><td></td></tr><tr><td>operating scissors&amp;nbsp;</td><td>Shanghai Medical Instrument (Group) Co.,Ltd.&amp;nbsp;</td><td>J21130</td><td></td></tr><tr><td>penicillin</td><td>Solarbio</td><td>140051251</td><td></td></tr><tr><td>Penicillin-streptomycin solution&amp;nbsp;</td><td>NovaCells</td><td>N-PSS125</td><td></td></tr><tr><td>povidone-iodine</td><td>Meilunbio</td><td>MB1313800g</td><td></td></tr><tr><td>scalpel blade</td><td>Shanghai Medical Instrument (Group) Co.,Ltd.</td><td>RYY070</td><td></td></tr><tr><td>scalpel handle</td><td>Shanghai Medical Instrument (Group) Co.,Ltd.&amp;nbsp;</td><td>J11010</td><td></td></tr><tr><td>suture&amp;nbsp;</td><td>Johnson &amp;amp; Johnson MEDICAL (CHINA) Ltd.&amp;nbsp;</td><td>SA84G</td><td></td></tr><tr><td>suture needle</td><td>Shanghai XIAOYU MEDICAL EQUIPMENTS.&amp;nbsp;</td><td>&amp;Delta;3/8 &amp;middot;3&amp;times;6</td><td></td></tr><tr><td>titanium needle</td><td>Tianjin Yutong Medical Device&amp;nbsp;</td><td>2-0X250&amp;nbsp;</td><td></td></tr><tr><td>toothed tissue forceps&amp;nbsp;</td><td>Shanghai Medical Instrument (Group) Co.,Ltd.&amp;nbsp;</td><td>J41055</td><td></td></tr><tr><td>Tramadol hydrochloride</td><td>Jiangsu Jiuxu Pharmaceutical Co., Ltd., China</td><td>CYHB2201997</td><td></td></tr><tr><td>Tubulin beta-III</td><td>sigma</td><td>CBL412X</td><td></td></tr><tr><td>Type I collagenase&amp;nbsp;</td><td>Thermo</td><td>17100-017</td><td></td></tr><tr><td>Zeiss Axio Vert A1 Inverted Fluorescence Microscope</td><td>Zeiss</td><td>Axio Vert A1</td><td></td></tr></tbody></table>

development of a novel internal fixation model for rat radial fractures: fracture healing assessment and dorsal root ganglion isolation

Development of a Novel Internal Fixation Model for Rat Radial Fractures: Fracture Healing Assessment and Dorsal Root Ganglion Isolation

The rat radial fracture model is of significant importance in orthopedic research, particularly for studying fracture-healing mechanisms, drug screening, and evaluating biological materials. Despite certain limitations, its role in scientific research remains irreplaceable. Since the radius of rats is relatively thin, the steel plates and screws currently used in clinical practice are not suitable for the treatment of rat radial fractures. To address this limitation, this study innovatively employs suture and titanium needle fixation, an internal fixation model for radial fractures that provides relatively stable fixation and establishes a robust animal model for investigating internal fixation of such fractures. In vivo imaging was performed using a live-animal micro-CT system to detect radial fracture healing in Sprague-Dawley (SD) rats. The extraction and application of the rat DRG are important steps in neuroscience research, widely used in fields such as neuroscience, pathology, and cell biology. This protocol is suitable for the primary culture of dorsal root ganglion neurons from rats with radial fractures and can be used to study mechanisms of nerve injury and repair after fractures, such as neuronal apoptosis and neurotransmitter release.

The micro-CT images confirmed the successful establishment of radial fracture rat models in Figure 7 and the internal fixation model for rat radial fractures in Figure 8. The micro-CT images were compared between taking on the day of constructing the internal fixation model of fracture and twenty days after the model establishment. Twenty days post-modeling, micro-CT analysis of SD rats in the fracture model group revealed a favorable prognosis. Images showed a ...

The study innovatively combines sutures and titanium needles for stable internal fixation in a rat radial fracture model. Fracture healing was assessed via micro-computed tomography (micro-CT), and primary dorsal root ganglion (DRG) neurons were isolated and cultured for further investigation.

The rat radial fracture model is of significant importance in orthopedic research, particularly for studying fracture-healing mechanisms, drug screening, ...

Radial fractures are highly prevalent globally and a leading cause of extremity long bone fractures. The rat radial fracture model is crucial for studying fracture healing, drug screening, and biomaterial evaluation in orthopedic research. Since the radius of rats it's relatively thin, the steel plates and screws currently used in clinical practice are not suitable for the treatment of rat radial fractures.To overcome this limitation, the protocol innovatively combines suture and titanium needle fixation, establishing a stable radial fracture model for internal fixation research. In the protocol, we also presented the use of the live animal micro-CT imaging system to clarify the fracture healing in rats. We also showed the extraction and culture of the DRG in the rat fracture model, which will be used to study the mechanism of nerve injury and repair in fractures.The rat fracture surgical instruments include scalpel blade, scalpel handle, operating scissors, needle holder, hemostatic forceps, and toothed tissue forceps. The male Sprague Dawley rat, approximately 8 weeks of age and weighing about 200 grams. Anesthetize the rat using an isoflurane gas anesthesia machine and maintain ventilatory anesthesia throughout the surgical procedure.Maintain the operating room temperature at 28 C.Place the rat in the lateral position. Expose the right forelimb, and shave off the hair using a hair clipper. Drape sterile sheet and wrap a tourniquet around the proximal right forelimb to reduce surgical bleeding.Prepare the skin by alternating alcohol and betadine scrubs three times. Make a 1.5 cm longitudinal incision on the dorsal radial side of the right forearm. Separate the muscle spaces and fully expose the right forelimb radius.Use operating scissors to cut the radius to create a transverse fracture. The direction of the scissors forms a 90-degree angle with the radius. Take a 0.8 mm diameter, 10 mm long titanium needle, and insert it into the radial fracture along its longitudinal axis.Fix the radius and the titanium needle with suture. The suture was tied with three consecutive knots, and the titanium needle was secured to the radius via four interrupted sutures. Suture the skin color of the excess suture and close the wood.Disinfect the skin with betadine scrubs. Cover the wound with sterile gauze and secure it with bandages. The rat regained consciousness after anesthesia and its condition recovered well.Anesthetize the rat using an isoflurane gas anesthesia machine. Place the rat in a prone position within the scanning chamber. Adjust limb and head positioning to center the target scanning area in the field of view and maintain continuous ventilation and anesthesia throughout the procedure.Push the fixed animal bed into the scanning chamber and close the chamber door. The micro-CT scanning parameters were set as follows:scan mode:standard, exposure time:two minutes, field of view:72 mm, voxel size:144 m, kilovolt:90;micro-amperes:88, filter:3D-soft. The scan data is automatically transmitted to the software, and three dimensional CT image is generated.Separate the target tissues. Export the processed images. Sever the spine, remove the C1 to C7 vertebral bodies.Cut the cervical spine along the anterior and posterior midlines, divided into left and right halves. Use toothed tissues forceps to pick up the DRG, gently lift it up and then use operating scissors to cut the nerve fibers. Transfer extracted DRGs to a 1.5 mL centrifuge tube with extraction medium.Place on ice. Slowly aspirate and discard the extraction medium. Add 1 mL of mixed digestive and enzyme working solution.Digest in a 37 C water bath for 60 to 70 minutes. Pipette an appropriate amount of the fibronectin working solution into a Petri dish and coat it in a 37 C incubator for an hour. Post digestion, aspirate, and discard the mixed digestive enzyme working solution.Collect filtrate, centrifuge at 70 x g for 8.5 minutes. After centrifugation, aspirate and discard the supernatant in the centrifuge tube. Add 1 mL of complete medium to resuspend the precipitate.Take out the Petri dish. Discard the fibronectin working solution and wash with PBS twice. Inoculate the cells into a Petri dish, add 1 mL of complete medium.Place them in a constant temperature incubator at 37 C with 5%carbon dioxide for 8-12 hours. The micro-CT imaging confirmed the successful establishment of radial fracture rat models and internal fixation model for rat radial fractures. 20 days post modeling, micro-CT analysis of SD rats in the fracture model group revealed favorable prognosis.Callus formation was observed bridging the fracture ends, with progressive fusion and gradual obliteration of the fracture line, which is consistent with the early phase of bone union. Images showed a blurred fracture line in the modeled region, suggesting that bone tissue at the fracture site had largely healed. On the 5th to 6th day after DRG isolation, neuronal cells exhibit extensive cytoplasmic exposure.At this stage, the entire neuronal cell bodies and their surrounding synapses are clearly distinguishable. Immunofluorescence microscopy was used to photograph neuronal cells on the 6th day of culture. As shown in Figure 9, Beta III-tubulin was shown as green fluorescence.Beta III-tubulin positive cells including both DRG cell bodies and axons were stained green, and the blue fluorescence represents the nuclei of neurons stained by DAPI. Rats are a classical model for studying the mechanism of fracture healing due to their clear genetic background and short reproductive cycle. However, the small radius diameter about 1-1.5 mm makes it impossible to match clinical-grade internal fixation device, severely restricting its utility in nerve-bone healing research.In response to this problem, this study innovatively proposed the combined suture titanium needle internal fixation method. The core logic is to replace the rigid fixation of screws with the flexible ligation of sutures, which could reduce the iatrogenic nerve injury and provide stable mechanical environment. This protocol provided repeatability and standardization for the construction of the model.The sutures and titanium needles are used for internal fixation in rat radial fracture models. Fracture healing is assessed via micro-CT. The primary DRG neurons are isolated and cultured following fracture healing examinations.In the protocol, we innovatively combine sutures and titanium needles for stable internal fixation in rat radial fracture model. Fracture healing was assessed via micro-CT, and primary DRG neurons were isolated and cultured for further investigation.

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Research

JoVE Journal

Biology

This article describes a method for stabilizing long bone fractures that is based on the application of modified Ilizarov external fixators 1-3. After application of the fixators and creation of the bone injury, healing can be assessed, distraction osteogenesis can be performed, or non-union or critical sized defect can be created and used to study therapeutic interventions.

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

Source: Cheah, M., et al. Dorsal Root Ganglion Injection and Dorsal Root Crush Injury as a Model for Sensory Axon Regeneration. J. Vis. Exp. (2017).This video demonstrates a step-by-step procedure for injecting a viral suspension into the dorsal root ganglia (DRGs) and inducing a controlled axonal injury via a dorsal root crush in an anesthetized rat. The protocol involves exposing the DRGs, delivering a growth-promoting viral vector to facilitate axonal regeneration, and severing axonal...

Modeling Sensory Axon Regeneration in a Rat Using Dorsal Root Ganglion Injection and Dorsal Root Crush Injury

One constraint of preclinical research in the field of bone repair is the lack of experimental control over the local mechanical environment within a healing bone lesion. We report the design and use of an external fixator for bone repair with the ability to change fixator stiffness in vivo.

Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models

This protocol describes an osteosynthesis technique using an intramedullary locking nail for standardized fixation of femur osteotomies, which can be used to analyze normal and defective bone healing in mice.

An Intramedullary Locking Nail for Standardized Fixation of Femur Osteotomies to Analyze Normal and Defective Bone Healing in Mice

This study describes a reproducible and detailed protocol using a newly developed external fixator for distraction osteogenesis (DO) in a femoral rat model which permits physiological weight-bearing by the animal after removal of the external fixator.

An Efficient and Reproducible Protocol for Distraction Osteogenesis in a Rat Model Leading to a Functional Regenerated Femur

This protocol describes a minimally invasive osteosynthesis technique using an intramedullary screw for standardized stabilization of femur fractures, which can be used to analyze endochondral bone healing in mice.

A Minimally Invasive Model to Analyze Endochondral Fracture Healing in Mice Under Standardized Biomechanical Conditions

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.

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

In vivo mammalian models of critical-sized bone defects are essential for researchers studying healing mechanisms and orthopedic therapies. Here, we introduce a protocol for the creation of reproducible, segmental, femoral defects in rats stabilized using external fixation.

A Reliable and Reproducible Critical-Sized Segmental Femoral Defect Model in Rats Stabilized with a Custom External Fixator

Here, we present a protocol to iatrogenically fracture the shaft of the femur of Wistar albino rats and follow up on the development of the callus. This femur osteotomy model can help researchers evaluate the process of fracture healing and to study how a drug could influence fracture healing.

Protocol for Developing a Femur Osteotomy Model in Wistar Albino Rats

This protocol describes a surgical procedure for the establishment of a diaphyseal fracture in the femur of mice, which is stabilized with an intramedullary wire, for fracture healing studies.

Establishing a Diaphyseal Femur Fracture Model in Mice

Here, we present a protocol for creating a box-cavity defect in rat femoral diaphysis tissue. This model can assess biomaterial performance under biomechanical stress and explore mechanisms of bone regeneration related to intramembranous osteogenesis.

Creating a Box-Cavity Defect Model in the Cortical Bone of Rat Femora

Learn a novel internal fixation method combining sutures and titanium needles for rat radial fractures. This protocol uses micro-CT imaging to assess bone healing and isolates dorsal root ganglion neurons to study nerve-bone repair mechanisms.

Development of a Novel Internal Fixation Model for Rat Radial Fractures: Fracture Healing Assessment and Dorsal Root Ganglion Isolation (Video) | JoVE Journal

Development of a Novel Internal Fixation Model for Rat Radial Fractures: Fracture Healing Assessment and Dorsal Root Ganglion Isolation

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