OBJECTIVE: To explore the effect of a modified three-point bending fracture device for establishing a rabbit model of closed tibial fracture. METHODS: The model of closed tibial fracture was established in 40 6-month-old male New Zealand white rabbits with a body weight of 2.5 to 3.0 kg, and the model was verified at 6 weeks after operation. Five rabbits underwent pre modeling without temporary external fixation before modeling, and then were fractured with a modified three-point bending fracture device;35 rabbits underwent formal modeling. Before modeling, needles were inserted, and splints were fixed externally, and then the fracture was performed with a modified three-point bending fracture device. The fracture model and healing process were evaluated by imaging and histopathology at 2 hours, 4 weeks, and 6 weeks after operation. RESULTS: Two hours after modeling, the prefabricated module showed oblique fracture in varying degrees and the broken end shifted significantly;Except for 1 comminuted fracture, 2 curved butterfly fractures and 2 without obvious fracture line, the rest were simple transverse and oblique fractures without obvious displacement in formal modeling group. According to the judgment criteria, the success rate of the model was 85.71%. Four weeks after modeling, the fixed needle and splint of the experimental rabbits were in good position, the fracture alignment was good, the fracture line was blurred, many continuous callus growths could be seen around the fracture end, and the callus density was high. Six weeks after modeling, many thick new bone trabeculae at the fracture, marginal osteoblasts attached, and a small number of macrophages were seen under the microscope. The intramembrane osteogenesis area was in the preparation bone stage, the medullary cavity at the fracture had been partially reopened, the callus was in the absorption plastic stage, and many osteoclasts were visible. The X-ray showed that the fracture line almost disappeared, part of the medullary cavity had been opened, the external callus was reduced around, the callus was in the plastic stage, and the bone cortex was continuous. It suggests that the fracture model showed secondary healing. CONCLUSION The improved three-point bending fracture device can establish a stable rabbit model of closed tibial fracture, and the operation is simple, which meets the requirements of closed fracture model in basic research related to fracture healing.
Rabbits ; Male ; Animals ; Bony Callus ; Fracture Healing ; Tibial Fractures/surgery* ; Osteogenesis ; Radiography

OBJECTIVE: To explore effects of isopsoralen (ISO) with different doses on fracture and vascular healing in mice. METHODS: Sixty 2-month-old male C57BL/6 mices with body mass of (20±2) g were selected and divided into 4 groups by random number table method:model group (model), low dose group (isopsoralen-low dose, ISO-L), medium dose group (isopsoralen-medium dose, ISO-M) and high dose group (isopsoralen-high dose, ISO-H), with 15 animals in each group. The right tibial fracture model was established. After operation, ISO-L group, ISO-M group and ISO-H group were given ISO concentration of 10 mg·kg^-1, 20 mg·kg^-1 and 40 mg·kg^-1, respectively. Model group was given same volume of normal saline once a day for 28 days. Weighed once a week. X-ray was performed on 7, 14, 21 and 28 days, respectively, and modified I.R. Garrett scoring method was used to evaluate callus growth. After 28 days, the main organs were stripped and weighed, and organ coefficients were calculated. Hematoxylin eosin staining (HE staining) was performed on the organs to observe whether there were pathological structural changes. Micro-computed tomography (Micro-CT) was used to scan fracture area and conduct three-dimensional reconstruction to obtain the effect map, and quantify bone volume fraction (bone volume/total volume, BV/TV). After decalcification, the tibia was embedded in paraffin wax and sectioned. The healing and shape of fracture end were observed by HE staining and ferruxin solid green staining. The right tibia was removed and decalcified after intravascular infusion of Microfil contrast agent. Micro-CT was used to scan the callus microvessels in the fracture area, and the vascular volume fraction and vessel diameter were quantified. RESULTS: After 28 days of administration, there was no significant difference in body mass and organ coefficient among all groups (P>0.05), and no significant pathological changes were found in HE staining of organs. The results of X-ray and improved I.R. Garrett score showed that ISO-M group was higher than that of Model group at 28 days (P<0.05). Scores of ISO-H group at 14, 21 and 28 days were higher than those of the other 3 groups (P<0.05). Micro-CT results showed intracavitary callus in ISO-M group was significantly reduced, which was lower than that in Model group (P<0.05), most of the callus in ISO-H group were subsided, and BV/TV in ISO-H group was lower than that in the other 3 groups (P<0.05). The results of HE staining and ferrubens solid green staining showed fracture area of ISO-H group was closed, continuous laminar bone had appeared, and the fracture healing process was higher than that of other groups. Angiographic results showed vascular volume fraction in ISO-H and ISO-M groups was higher than that in Model and ISO-L groups (P<0.05), and the vascular diameter in ISO-H and ISO-M groups was higher than that in Model and ISO-L groups (P<0.05). CONCLUSION In the concentration range of 10-40 mg·kg^-1, ISO has no obvious toxic and side effects, and could improve bone microstructure, promote formation of callus microvessels, and accelerate healing of fracture ends in a concentration-dependent manner.
Mice ; Male ; Animals ; X-Ray Microtomography ; Mice, Inbred C57BL ; Bony Callus ; Fracture Healing ; Tibial Fractures/surgery*

callus was evaluated using contrast-enhanced ultrasonography (CEUS) in a canine osteotomy model to determine the applicability of CEUS in the assessment of neovascularization during fracture healing and to compare the vascular signals on CEUS between external skeletal fixation and cast-applied dogs. In 6 Beagle dogs, a simple transverse osteotomy was performed at the left tibial shaft and external skeletal fixation (n = 3) or a cast (n = 3) was applied. Radiography, power Doppler ultrasonography (power Doppler), and CEUS were performed until complete union was achieved. On CEUS, vascular changes were quantitatively evaluated by measuring peak intensity (PI) and time to PI in the soft tissue and callus and by counting the vascular signals. Vascular signals from the soft tissue were detected on power Doppler and CEUS on day 2. Significantly more vascular signals were detected by CEUS than by power Doppler. On CEUS, PI in the surrounding soft tissue was markedly increased after the fracture line appeared indistinctively changed on radiography in all dogs. In the cast-applied dogs, vascular signals from the periosteal and endosteal callus were detected on CEUS before mineralized callus was observed on radiography. CEUS was useful in assessing the vascularity of soft tissue and callus, particularly in indirect fracture healing, and provided indications of a normally healing fracture.]]>
Animals ; Bony Callus ; Diagnostic Imaging ; Dogs ; Fracture Fixation ; Fracture Healing ; Microbubbles ; Miners ; Muscle, Skeletal ; Osteotomy ; Perfusion ; Radiography ; Ultrasonography ; Ultrasonography, Doppler

We performed a revisionary open reduction and internal fixation for treating nonunion of the mid-shaft of the left clavicle with an autogenous cancellous bone graft. On postoperative day 4, the patient presented with neurologic deficits in the left upper extremity. We removed the implant and made a superior angulation to decompress the brachial plexus. At 6 months postoperatively, callus bridging and consolidation were visible and all hand and elbow functions were fully recovered. Our case suggests that brachial plexus neuropathy may be caused by stretching and compression after reduction and straightening of the nonunion site around adhesions or scar tissue. Therefore, care should be taken whether there are the risk factors that can cause brachial plexus neuropathy when revision surgery is performed for treating nonunion of a clavicle shaft fracture.
Bony Callus ; Brachial Plexus Neuropathies ; Brachial Plexus ; Cicatrix ; Clavicle ; Elbow ; Hand ; Humans ; Neurologic Manifestations ; Risk Factors ; Transplants ; Upper Extremity

We assessed the efficacy of frozen-thawed gelatin-induced osteogenic cell sheet (FT-GCS) compared to that of fresh gelatin-induced osteogenic cell sheet (F-GCS) with adipose-derived mesenchymal stromal cells (Ad-MSCs) used as the control. The bone differentiation capacity of GCS has already been studied. On that basis, the experiment was conducted to determine ease of use of GCS in the clinic. In vitro evaluation of F-GCS showed 3–4 layers with an abundant extracellular matrix (ECM) formation; however, cryopreservation resulted in a reduction of FT-GCS layers to 2–3 layers. Cellular viabilities of F-GCS and FT-GCS did not vary significantly. Moreover, there was no significant difference in mRNA expressions of Runx2, β-catenin, OPN, and BMP-7 between F-GCS and FT-GCS. In an in vivo experiment, both legs of six dogs with transverse radial fractures were randomly assigned to one of three groups: F-GCS, FT-GCS, or control. Fracture sites were wrapped with the respective cell sheets and fixed with 2.7 mm locking plates and six screws. At 8 weeks after the operations, bone samples were collected and subjected to micro computed tomography and histopathological examination. External volumes of callus as a portion of the total bone volume in control, F-GCS, and FT-GCS groups were 49.6%, 45.3%, and 41.9%, respectively. The histopathological assessment showed that both F-GCS and FT-GCS groups exhibited significantly (p < 0.05) well-organized, mature bone with peripheral cartilage at the fracture site compared to that of the control group. Based on our results, we infer that the cryopreservation process did not significantly affect the osteogenic ability of gelatin-induced cell sheets.
Animals ; Bone Morphogenetic Protein 7 ; Bony Callus ; Cartilage ; Cryopreservation ; Dogs ; Extracellular Matrix ; Fracture Healing ; In Vitro Techniques ; Leg ; Mesenchymal Stromal Cells ; RNA, Messenger

Forearm fractures are common injuries in childhood. Median nerve entrapment is a rare complication of forearm fractures, but several cases have been reported in the literature. This case report discusses the diagnosis and management of median nerve entrapment in a 13-year-old male who presented acutely with a both-bone forearm fracture and numbness in the median nerve distribution. Following the delayed diagnosis, surgical exploration revealed complete nerve entrapment and a nerve graft was performed.
Adolescent ; Bony Callus ; Delayed Diagnosis ; Diagnosis ; Forearm Injuries ; Forearm ; Fractures, Bone ; Humans ; Hypesthesia ; Male ; Median Nerve ; Nerve Compression Syndromes ; Transplants

The brachial plexus palsy is a rare complication of a clavicle fracture, occurring in 0.5% to 9.0% of cases. This condition is caused by excessive callus formation, which can be recovered by a spur resection and surgical fixation. In contrast, only seven cases have been reported after surgical reduction and fixation. A case of progressive brachial plexus palsy was observed after fixation of the displaced nonunion of a clavicle fracture. The symptom were improved after removing the implant.
Bony Callus ; Brachial Plexus Neuropathies ; Brachial Plexus ; Clavicle ; Paralysis ; Thoracic Outlet Syndrome

Physical forces agents may induce distinctive skin changes. Pressure and friction induce callus and corn. Callus and corn arise at sites of friction or pressure, particularly palms and soles, and especially the bony prominences of the joints. Pressure, shearing forces, friction, and moisture are main etiologic factors of pressure ulcer. The pressure ulcer is caused by ischemia of the underlying structures of the skin, fat, and muscles. Skin has long been known to be a very radiosensitive organ. Skin changes after radiation exposure follow a predictable course dictated by radiation dose, timing, and the biology of the human inflammatory reaction. When the skin is exposed to radiation, acute radiation dermatitis, chronic radiation dermatitis, skin cancer, and radiation recall dermatitis may be developed.
Biology ; Bony Callus ; Dermatitis ; Friction ; Humans ; Ischemia ; Joints ; Muscles ; Pressure Ulcer ; Radiation Exposure ; Radiodermatitis ; Skin ; Skin Diseases ; Skin Neoplasms ; Zea mays

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare disease that affects the sensory and autonomic nervous system. The patients do not have the ability to sense different sensations, such as pain, which tends to lead to different injuries. In addition, the patients suffer from fluctuations in body temperature due to autonomic involvement. The present case was a five-year-old girl with a neglected distal femur fracture. X-rays taken during the follow-up showed marked callus formation and pseudarthrosis of the distal femur. She had biting injuries of the tongue, auto-amputation of the fingers, some developmental delay and a history of recurrent fever with an unknown origin. The electrodiagnostic study was normal. The quantitative sudomotor axon reflex test revealed markedly reduced postganglionic sudomotor axonal responses at all sites recorded on the left. She was diagnosed with CIPA. As the initial presentation of CIPA involves the musculoskeletal system, orthopedic surgeons should have a high index of suspicion.
Autonomic Nervous System ; Axons ; Body Temperature ; Bony Callus ; Female ; Femur ; Fever ; Fingers ; Follow-Up Studies ; Hereditary Sensory and Autonomic Neuropathies ; Humans ; Musculoskeletal System ; Orthopedics ; Pain Insensitivity, Congenital ; Pseudarthrosis ; Rare Diseases ; Reflex ; Sensation ; Surgeons ; Tongue

Cell sheets technology is being available for fracture healing. This study was performed to clarify bone healing mechanism of undifferentiated (UCS) and osteogenic (OCS) differentiated mesenchymal stromal cell (MSC) sheets in the fracture model of dogs. UCS and OCS were harvested at 10 days of culture. Transverse fractures at the radius of six beagle dogs were assigned into three groups (n = 4 in each group) i.e. UCS, OCS and control. The fractures were fixed with a 2.7 mm locking plate and six screws. Cell sheets were wrapped around the fracture site. Bones were harvested 8 weeks after operation, then scanned by micro-computed tomography (micro-CT) and analyzed histopathologically. The micro-CT revealed different aspects of bone regeneration among the groups. The percentages of external callus volume out of total bone volume in control, UCS, and OCS groups were 42.1, 13.0 and 4.9% (p < 0.05) respectively. However, the percentages of limbs having connectivity of gaps were 25, 12.5 and 75% respectively. In histopathological assessments, OCS group showed well organized and mature woven bone with peripheral cartilage at the fracture site, whereas control group showed cartilage formation without bone maturation or ossification at the fracture site. Meanwhile, fracture site was only filled with fibrous connective tissue without endochondral ossification and bone formation in UCS group. It was suggested that the MSC sheets reduced the quantity of external callus, and OCS induced the primary bone healing.
Animals ; Bone Regeneration ; Bony Callus ; Cartilage ; Connective Tissue ; Dogs ; Extremities ; Fracture Healing ; Mesenchymal Stromal Cells ; Osteogenesis ; Radius