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Scientific Reports Oct 2016Bone callus, generated during fracture healing, is commonly discarded during surgical procedures. The aim of this study was to investigate the osteogenic potential of...
Bone callus, generated during fracture healing, is commonly discarded during surgical procedures. The aim of this study was to investigate the osteogenic potential of bone callus and its possible use as autograft material for patients needing bone grafts. Histology, immunohistochemistry, micro-computed tomography, and biomechanics were performed to examine osteogenic cells, osteoinductive factors, and the osteoconductive structure of bone callus. Alkaline phosphatase-positive osteoblasts, osteoinductive factors (including BMP2, FGF2, TGFB1, and IGF1), and a porous structure were found in bone callus. Early-stage callus (within 3 months after fracture) presented significantly improved osteogenic properties compared to medium- (3-9 months) and late-stage (longer than 9 months) callus. The results revealed that bone callus induced new bone formation in a nude mouse model. Early-stage callus showed better performance to medium- and late-stage callus in the induction of new bone formation at both 8 and 12 weeks. These findings indicated that bone callus, especially early-stage callus, possesses osteogenic potential and can potentially serve as an alternative source of material for bone grafts.
Topics: Adult; Alkaline Phosphatase; Animals; Bone Transplantation; Bony Callus; Female; Humans; Male; Mice; Mice, Nude; Middle Aged; Osteoblasts; Osteogenesis; X-Ray Microtomography
PubMed: 27796345
DOI: 10.1038/srep36330 -
Biomechanics and Modeling in... Apr 2022Bone healing has been traditionally described as a four-phase process: inflammatory response, soft callus formation, hard callus development, and remodeling. The...
Bone healing has been traditionally described as a four-phase process: inflammatory response, soft callus formation, hard callus development, and remodeling. The remodeling phase has been largely neglected in most numerical mechanoregulation models of fracture repair in favor of capturing early healing using a pre-defined callus domain. However, in vivo evidence suggests that remodeling occurs concurrently with repair and causes changes in cortical bone adjacent to callus that are typically neglected in numerical models of bone healing. The objective of this study was to use image processing techniques to quantify this early-stage remodeling in ovine osteotomies. To accomplish this, we developed a numerical method for radiodensity profilometry with optimization-based curve fitting to mathematically model the bone density gradients in the radial direction across the cortical wall and callus. After assessing data from 26 sheep, we defined a dimensionless density fitting function that revealed significant remodeling occurring in the cortical wall adjacent to callus during early healing, a 23% average reduction in density compared to intact. This fitting function is robust for modeling radial density gradients in both intact bone and fracture repair scenarios and can capture a wide variety of the healing responses. The fitting function can also be scaled easily for comparison to numerical model predictions and may be useful for validating future mechanoregulatory models of coupled fracture repair and remodeling.
Topics: Animals; Bony Callus; Fracture Healing; Fractures, Bone; Sheep
PubMed: 34997398
DOI: 10.1007/s10237-021-01553-2 -
Acta Cirurgica Brasileira Feb 2019To evaluate the effects of food restriction on fracture healing in growing rats.
PURPOSE
To evaluate the effects of food restriction on fracture healing in growing rats.
METHODS
Sixty-eight male Wistar rats were assigned to two groups: (1) Control and (2) Dietary restriction. After weaning the dietary restricted animals were fed ad libitum for 42 days with 50% of the standard chow ingested by the control group. Subsequently, the animals underwent bone fracture at the diaphysis of the right femur, followed by surgical stabilization of bone fragments. On days 14 and 28 post-fracture, the rats were euthanized, and the fractured femurs were dissected, the callus was analyzed by dual-energy X-ray absorptiometry, micro-computed tomography, histomorphometry, mechanical tests, and gene expression.
RESULTS
Dietary restriction decreased body mass gain and resulted in several phenotypic changes at the bone callus (a delay in cell proliferation and differentiation, lower rate of newly formed bone and collagen deposition, reductions in bone callus density and size, decrease in tridimensional callus volume, deterioration in microstructure, and reduction in bone callus strength), together with the downregulated expression of osteoblast-related genes.
CONCLUSION
Dietary restriction had detrimental effects on osseous healing, with a healing delay and a lower quality of bone callus formation.
Topics: Animals; Bone Density; Bony Callus; Femoral Fractures; Fracture Fixation, Intramedullary; Fracture Healing; Fractures, Closed; Male; Malnutrition; Osteoporosis; Rats; Rats, Wistar
PubMed: 30785503
DOI: 10.1590/s0102-865020190010000002 -
Journal of Orthopaedic Research :... May 2015Type III collagen (Col3) has been proposed to play a key role in tissue repair based upon its temporospatial expression during the healing process of many tissues,...
Type III collagen (Col3) has been proposed to play a key role in tissue repair based upon its temporospatial expression during the healing process of many tissues, including bone. Given our previous finding that Col3 regulates the quality of cutaneous repair, as well as our recent data supporting its role in regulating osteoblast differentiation and trabecular bone quantity, we hypothesized that mice with diminished Col3 expression would exhibit altered long-bone fracture healing. To determine the role of Col3 in bone repair, young adult wild-type (Col3+/+) and haploinsufficent (Col3+/-) mice underwent bilateral tibial fractures. Healing was assessed 7, 14, 21, and 28 days following fracture utilizing microcomputed tomography (microCT), immunohistochemistry, and histomorphometry. MicroCT analysis revealed a small but significant increase in bone volume fraction in Col3+/- mice at day 21. However, histological analysis revealed that Col3+/- mice have less bone within the callus at days 21 and 28, which is consistent with the established role for Col3 in osteogenesis. Finally, a reduction in fracture callus osteoclastic activity in Col3+/- mice suggests Col3 also modulates callus remodeling. Although Col3 haploinsufficiency affected biological aspects of bone repair, it did not affect the regain of mechanical function in the young mice that were evaluated in this study. These findings provide evidence for a modulatory role for Col3 in fracture repair and support further investigations into its role in impaired bone healing.
Topics: Animals; Bone Regeneration; Bony Callus; Cell Proliferation; Collagen Type III; Female; Fracture Healing; Mice; Osteoclasts; Tibial Fractures; X-Ray Microtomography
PubMed: 25626998
DOI: 10.1002/jor.22838 -
Journal of Orthopaedic Research :... Aug 2023Fracture burden has created a need to better understand bone repair processes under different pathophysiological states. Evaluation of structural and material properties...
Fracture burden has created a need to better understand bone repair processes under different pathophysiological states. Evaluation of structural and material properties of the mineralized callus, which is integral to restoring biomechanical stability is, therefore, vital. Microcomputed tomography (micro-CT) can facilitate noninvasive imaging of fracture repair, however, current methods for callus segmentation are only semiautomated, restricted to defined regions, time/labor intensive, and prone to user variation. Herein, we share a new automatic method for segmenting callus in micro-CT tomograms that will allow for objective, quantitative analysis of the bone fracture microarchitecture. Fractured and nonfractured mouse femurs were scanned and processed by both manual and automated segmentation of fracture callus from cortical bone after which microarchitectural parameters were analyzed. All segmentation and analysis steps were performed using CTAn (Bruker) with automatic segmentation performed using the software's image-processing plugins. Results showed automatic segmentation reliably and consistently segmented callus from cortical bone, demonstrating good agreement with manual methods with low bias: tissue volume (TV): -0.320 mm , bone volume (BV): 0.0358 mm , and bone volume/tissue volume (BV/TV): -3.52%, and was faster and eliminated user-bias and variation. Method scalability and translatability across rodent models were verified in scans of fractured rat femora showing good agreement with manual methods with low bias: TV: -3.654 mm , BV: 0.830 mm , and BV/TV: 7.81%. Together, these data validate a new automated method for segmentation of callus and cortical bone in micro-CT tomograms that we share as a fast, reliable, and less user-dependent tool for application to study bone callus in fracture, and potentially elsewhere.
Topics: Rats; Mice; Animals; X-Ray Microtomography; Rodentia; Bony Callus; Femur; Femoral Fractures
PubMed: 36582023
DOI: 10.1002/jor.25507 -
Critical Reviews in Eukaryotic Gene... 2010The failure of an osseous fracture to heal, or the development of a nonunion, is common; however, current diagnostic measures lack the capability of early and reliable... (Review)
Review
The failure of an osseous fracture to heal, or the development of a nonunion, is common; however, current diagnostic measures lack the capability of early and reliable detection of such events. Analyses of radiographic imaging and clinical examination, in combination, remain the gold standard for diagnosis; however, these methods are not reliable for early detection. Delayed diagnosis of a nonunion is costly from both the patient and treatment standpoints. In response, repeated efforts have been made to identify bone metabolic markers as diagnostic or prognostic tools for monitoring bone healing. Thus far, the evidence regarding a correlation between the kinetics of most bone metabolic markers and nonunion is very limited. With the aim of classifying the role of biological pathways of bone metabolism and of understanding bone conditions in the development of osteoporosis, advances have been made in our knowledge of the molecular basis of bone remodeling, fracture healing, and its failure. Procollagen type I amino-terminal propeptide has been shown to be a reliable bone formation marker in osteoporosis therapy and its kinetics during fracture healing has been recently described. In this article, we suggest that procollagen type I amino-terminal propeptide presents a good opportunity for early detection of nonunion. We also review the role and potential of serum PINP, as well as other markers, as indications of fracture healing.
Topics: Biomarkers; Bony Callus; Fracture Healing; Humans; Osteogenesis; Osteoporosis; Prognosis
PubMed: 21133841
DOI: 10.1615/critreveukargeneexpr.v20.i2.20 -
Molecular Medicine Reports May 2017Fracture healing involves the coordinated actions of multiple cytokines. Bone morphogenetic protein 9 (BMP9) is an important factor in bone formation. The present study...
Fracture healing involves the coordinated actions of multiple cytokines. Bone morphogenetic protein 9 (BMP9) is an important factor in bone formation. The present study aimed to investigate the osteogenic potential of bone marrow stem cells (BMSCs) in response to adenoviral (Ad)BMP9, and the early fracture repair properties of AdBMP9 in surgically‑created fractures in osteoporotic rats. Alkaline phosphatase (ALP) activity was assayed and matrix mineralization was examined by Alizarin Red S staining. mRNA and protein expression levels of BMP9, runt‑related transcription factor 2 (RUNX2) and type 1 collagen (COL‑1) were detected in vitro and in vivo. Femoral bone mineral density was assessed for osteoporosis in ovariectomized rats. An open femora fracture was subsequently created, and gelatin sponges containing AdBMP9 were implanted. The femora were harvested for radiographical, micro‑computed tomography, biomechanical and histological analysis 4 weeks later. BMP9 successfully increased ALP activity and induced mineralized nodule formation in BMSCs. BMP9 in gelatin sponges demonstrated marked effects on microstructural parameters and the biomechanical strength of bone callus. In addition, it upregulated the expression levels of RUNX2 and COL‑1. AdBMP9 in gelatin sponges significantly mediated callus formation, and increased bone mass and strength in osteoporotic rats with femora fractures. The results of the present study suggested that BMP9 enhanced callus formation and maintained early mechanical stability during fracture healing in osteoporotic rats, implicating it as a potential novel therapeutic target for fracture healing.
Topics: Adenoviridae; Animals; Bony Callus; Female; Femoral Fractures; Fracture Healing; Growth Differentiation Factor 2; Osteoporosis; Rats; Rats, Sprague-Dawley; Transduction, Genetic
PubMed: 28447742
DOI: 10.3892/mmr.2017.6302 -
Journal of Orthopaedic Surgery and... Jul 2019The positive effects of grape seed proanthocyanidin extract (GSPE) on bone health, which is a potent antioxidant, are known but its effects on fracture healing are not...
BACKGROUND
The positive effects of grape seed proanthocyanidin extract (GSPE) on bone health, which is a potent antioxidant, are known but its effects on fracture healing are not sufficiently covered in the literature. This study aims to investigate the effects of GSPE on fracture healing and biomechanics of healing bone.
MATERIALS AND METHODS
Sixty-four adult Wistar-Albino male rats were divided into 8 groups of 8 animals in each group. Osteotomy was performed to the right femurs of all groups except the negative control (G1) and positive control (G2) groups, and intramedullary Kirchner wire was used for fixation. GSPE was given to half of the rats (G2-G4-G6-G8) 100 mg/kg/day by oral gavage. The rats were sacrificed on the tenth (G3-G4), twentieth (G5-G6), and thirtieth (G1-G2-G7-G8) days, respectively, and histopathological, radiological, and biomechanical examinations were performed.
RESULTS
Histopathological examination of the specimens from the callus tissues revealed that bone healing was more prominent in the groups supplemented with GSPE (G4, G6, G8). There was a statistically significant improvement in radiological recovery scores and callus volumes in groups with GSPE. When biomechanical strengths were evaluated, it was found that GSPE increased bone strength not only in fracture groups but also in the positive control group (G2).
CONCLUSIONS
As a result, this study showed that GSPE, a potent anti-oxidant, had a positive effect on bone healing and improved mechanical strength of the healing bone.
Topics: Animals; Antioxidants; Biomechanical Phenomena; Bony Callus; Compressive Strength; Dietary Supplements; Femur; Grape Seed Extract; Male; Rats; Rats, Wistar
PubMed: 31277691
DOI: 10.1186/s13018-019-1251-5 -
Journal of Visualized Experiments : JoVE Dec 2022Micro-computed tomography (µCT) is the most common imaging modality to characterize the three-dimensional (3D) morphology of bone and newly formed bone during fracture...
Micro-computed tomography (µCT) is the most common imaging modality to characterize the three-dimensional (3D) morphology of bone and newly formed bone during fracture healing in translational science investigations. Studies of long bone fracture healing in rodents typically involve secondary healing and the formation of a mineralized callus. The shape of the callus formed and the density of the newly formed bone may vary substantially between timepoints and treatments. Whereas standard methodologies for quantifying parameters of intact cortical and trabecular bone are widely used and embedded in commercially available software, there is a lack of consensus on procedures for analyzing the healing callus. The purpose of this work is to describe a standardized protocol that quantitates bone volume fraction and callus mineral density in the healing callus. The protocol describes different parameters that should be considered during imaging and analysis, including sample alignment during imaging, the size of the volume of interest, and the number of slices that are contoured to define the callus.
Topics: Fracture Healing; X-Ray Microtomography; Bony Callus; Osteogenesis
PubMed: 36571411
DOI: 10.3791/64262 -
Calcified Tissue International Jul 2004The aim of this study was to determine the ability of the following bone turnover markers to monitor the course of callus consolidation during bone healing:...
The aim of this study was to determine the ability of the following bone turnover markers to monitor the course of callus consolidation during bone healing: Carboxy-terminal propeptide of procollagen type I (PICP), skeletal alkaline phosphatase (sALP), and amino-terminal propeptide of type III procollagen (PIlINP). Since interfragmentary movements have been proven to possess the ability to document the progression of bone healing in experimental studies, correlations between bone turnover markers and interfragmentary movements in vivo were investigated. Therefore, two different types of osteosyntheses representing different mechanical situations at the fracture site were compared in an ovine osteotomy model. Blood samples were taken preoperatively and postoperatively in weekly intervals over a nine-week healing period. At the same intervals, interfragmentary movements were measured in all sheep. After nine weeks, animals were sacrificed and the tibiae were evaluated both mechanically and histologically. Wide interindividual ranges were observed for all bone turnover markers. The systemic PICP level did not increase with callus consolidation. The bone-healing model seemed to influence the systemic level of PIIINP and sALP but no general correlation between bone turnover markers and interfragmentary movements could be detected. No differences between the different types of osteosyntheses and thus the different mechanical situations were observed. All analyzed markers failed as general predictors for the course of callus consolidation during bone healing.
Topics: Alkaline Phosphatase; Animals; Biomarkers; Bony Callus; Disease Models, Animal; External Fixators; Female; Fracture Healing; Osteogenesis; Osteotomy; Peptide Fragments; Predictive Value of Tests; Procollagen; Sheep; Stress, Mechanical; Tibia; Tibial Fractures; Weight-Bearing
PubMed: 15148561
DOI: 10.1007/s00223-004-0183-0