Bone Callus Formation Research Articles

Advances on T cell immunity in bone remodeling and bone regeneration.

Bone remodeling and bone regeneration are essential for preserving skeletal integrity and maintaining mineral homeostasis. T cells, as key members of adaptive immunity, play a pivotal role in bone remodeling and bone regeneration by producing a range of cytokines and growth factors. In the physiological state, T cells are involved in the maintenance of bone homeostasis through interactions with mesenchymal stem cells, osteoblasts, and osteoclasts. In pathological states, T cells participate in the pathological process of different types of osteoporosis through interaction with estrogen, glucocorticoids, and parathyroid hormone. During fracture healing for post-injury repair, T cells play different roles during the inflammatory hematoma phase, the bone callus formation phase and the bone remodeling phase. Targeting T cells thus emerges as a potential strategy for regulating bone homeostasis. This article reviews the research progress on related mechanisms of T cells immunity involved in bone remodeling and bone regeneration, with a view to providing a scientific basis for targeting T cells to regulate bone remodeling and bone regeneration.

Use of tie-in femur osteosynthesis in free-living aracuã scamoso (ortalis squamata) with blockage of the femoral and ischiatic nerves

We report the case of an adult scaly-breasted arachnid, which arrived for treatment with a history of being on the ground in the courtyard of a house, unable to stay in a station. On clinical examination, the bird had an immobile right femur, with a probable comminuted fracture, and the decision was made to perform a surgical procedure to correct the fracture. The treatment used the tie-in technique, where a 1.2 mm intramedullary pin was placed in the femur for initial alignment of the bone fragments, while external fixation was carried out with three pins of the same thickness as the previous one, two in the cranial region and one in the region distal to the fracture site. Two months after the surgery, an X-ray was taken to check for the formation of bone callus, with a satisfactory result. The external fixator was removed the following day, and seven days after removal the bird was discharged and released. As well as the tie-in technique having a high success rate with a complete return of function, it has the advantage that its implants are removable, which is important when the animal is returned to the wild, preventing these implants from remaining in the environment if it dies.

Promoting bone callus formation by taking advantage of the time-dependent fracture gap strain modulation.

Delayed union and non-union of fractures continue to be a major problem in trauma and orthopedic surgery. These cases are challenging for the surgeon. In addition, these patients suffer from multiple surgeries, pain and disability. Furthermore, these cases are a major burden on healthcare systems. The scientific community widely agrees that the stability of fixation plays a crucial role in determining the outcome of osteosynthesis. The extent of stabilization affects factors like fracture gap strain and fluid flow, which, in turn, influence the regenerative processes positively or negatively. Nonetheless, a growing body of literature suggests that during the fracture healing process, there exists a critical time frame where intervention can stimulate the bone's return to its original form and function. This article provides a summary of existing evidence in the literature regarding the impact of different levels of fixation stability on the strain experienced by newly forming tissues. We will also discuss the timing and nature of this "window of opportunity" and explore how current knowledge is driving the development of new technologies with design enhancements rooted in mechanobiological principles.

Investigating the Clinical, Radiological and Histopathological Effects of Androgens in Bone Formation and Fracture Healing By IJISRT

Background and Purpose: How to use steroid hormones as a solution and indicator in bone fractures and healing in sterilized or unsterilized male animals and even in female animals and animals that have a deficiency and disorder of steroid hormones.  Research Method: Ten apparently healthy adult male rabbits were selected from the laboratory and were sterilized by scrotal method, and four holes with diameters of 1, 2, 3, and 4 mm were inserted on the tibia from the lateral side, and then into two The group was divided. Regarding the time evaluation of radiographs, which had a normal distribution, variance analysis tests were used at a significant level of 0.05. About the status of the steps that were in the ranking scale. Kruskal-Wallis test was used and statistical calculations were done using SPSS statistical program.  Results: The gait status of rabbits in both groups improves significantly from day one to day 60. On the other hand, there is no significant difference between the two groups at different times and between different times in each group. Except for the first and seventh day, this difference is completely normal. In relation to the amount of callus formed in the two groups, there is a significant difference at some times. From the point of view of pathology, the assessment of the first and second groups indicated the occurrence of restoration and bone callus formation in both groups, but in comparison, the first group had a wider and more voluminous callus. The whole restoration process had more advanced stages.

Gefitinib enhances healing of long bone fractures in rats via inhibition of the epidermal growth factor receptor signal pathway

Purpose: To investigate the influence of gefitinib on healing of long bone fractures in rats, and the involvement of epidermal growth factor receptor (EGFR) signal route in the process.
 Methods: A model of long bone fracture was established in 30 Sprague-Dawley (SD) rats which were allocated to control and study groups (n = 15/group). Rats in study group received gefitinib (100 mg/kg per day) via gavage, while control rats were given 0.55 % methylcellulose daily for 7 - 42 days. Fracture healing, maximum callus diameter, serum levels of bone markers and mRNA levels of bone turnover indices in the callus, were determined.
 Results: Following 1 week of therapy, fracture lines were clear in both groups, and callus was produced. On days 7, 14, 21, and 28, maximum callus diameter of study group was significantly higher than that of control group (p < 0.05). However, there was no significant difference in the maximum callus diameter between the two groups after 42 days (p > 0.05). On days 7, 14 and 21, there were significantly higher BALP and PINP levels, and TRACP-5b and CTX values in study group than in control (p < 0.05). On days 7 and 14, study group COLa1 mRNA and osteocalcin (OC) mRNA was significantly raised, relative to control values. On days 7, 14 and 21, COL10 mRNA expression was significantly up-regulated in study group relative to controls (p < 0.05). However, mRNA expression levels of COLa1, OC, COL10, and COL2A1 were similar in both groups at other time points.
 Conclusion: Gefitinib enhances the healing of long bone fractures and callus formation in rats, probably through inhibition of EGFR signaling pathway. Therefore, gefitinib is beneficial in bone formation in rats.

Combined osteosynthesis for tibial shaft fracture treatment

Introduction Widespread use of intramedullary and extramedullary implants, as well as external fixation devices, has demonstrated that current surgical methods are not always successful.The study aimed to assess the efficiency of a combination of transosseous osteosynthesis with intramedullary reinforcement using elastic titanium hydroxyapatite-coated rods (HA-rods) in long bone fracture treatment.Material and methods Medical records of 40 patients aged from 18 to 55 years with closed diaphyseal tibia fractures of A1-A3 type (AO/ASIF) treated with the Ilizarov transosseous osteosynthesis method combined with intramedullary elastic HA-coated wires were analysed. Result Ilizarov fixator removal was performed on average 45.3 ± 14.7 days after surgery. Radiological signs of bone union (immature callus, patterns of periosteal and endosteal stratifications overlapping the fracture line) were visible by week 3 to 4.Discussion Соmbination of the external fixator and intramedullary elastic HA-coated wires overcomes shortcomings of both external and internal means of fixation. External osteosynthesis provides advantages of the Ilizarov method: preservation of blood supply, absence of soft tissue injury, joint function and early weightbearing. Elastic intramedullary wires do not injure a. nutricia and mechanically stimulate endosteal and periosteal bone formation.Conclusion The advantages of combined osteosynthesis provide reduction of Ilizarov apparatus fixation time, reduction in the number of wires and half-pins in the frame assembly, stimulation of bone callus formation and prevention of secondary bone fragment displacement.

PECULIARITIES OF THE TREATMENT APPROACH FOR HUMERAL DIAPHYSIS FRACTURES IN PATIENTS WITH COMORBIDITIES

Humeral diaphysis fractures are one of the frequent components of the low-energy trauma in people of different age and gender groups with comorbid pathology. Pathological autoimmune and trophic processes that disrupt the reparative capabilities of the body have a negative impact on the formation of connective tissue. The purpose of this study is to identify the peculiarities of the treatment for humeral diaphysis fractures in patients with comorbid pathology. Methods and Material. 42 patients with humeral diaphysis fractures, aged 18 to 88 years, have been involved in the study. All patients were diagnosed to have comorbid pathology affecting the regenerative processes of bone and connective tissues. Type 1 and Type 2 diabetes mellitus was diagnosed in 71.4% (30) and 28.6% (12) patients, respectively. In 28.8% (12) cases, erythrodermic psoriasis without psoriatic arthro- and enthesopathies was diagnosed. The treatment for humeral diaphysis fractures in all studied cases was carried out using the surgical techniques. Results and Discussion. 2 clinical groups of patients were distinguished depending on the applied method of osteosynthesis. The evaluation of the treatment outcomes was carried out according to a number of parameters, namely the presence of complications of combined genesis during the healing of postoperative wounds and prolongation of the repair phase for fracture consolidation and bone callus formation. Conclusions. The risk for postoperative complications among patients with injuries of the humeral diaphysis with underlying erythrodermic psoriasis and Type1 and Type 2 diabetes mellitus can be reduced by minimizing the surgical interventions and applying minimally invasive surgery.

Menière's Syndrome Associated With Fibrous Dysplasia of the Temporal Bone.

Menière's Syndrome Associated With Fibrous Dysplasia of the Temporal Bone.

EARLY PHYSICAL REHABILITATION FOLLOWING FRACTURE INCREASES OSTEOCHONDRAL CALLUS FORMATION IN A PRECLINICAL MODEL OF DISUSE

Patients with bone and muscle weakness from disuse have higher risk of fracture and worse post-injury mortality rates. The goal of this current study was to better inform post-fracture rehabilitation strategies by investigating if physical remobilization following disuse by hindlimb unloading improves osteochondral callus formation compared to continued disuse by hindlimb suspension (HLS). We hypothesized that continued HLS would impair callus bone and cartilage formation and that physical rehabilitation after HLS would increase callus properties.All animal procedures were approved by the VCU IACUC. Skeletally mature, male and female C57BL/6J mice (18 weeks) underwent HLS for 3 weeks. Mice then had their right femur fractured by open surgical dissection (stabilized with 24-gauge pin). Mice were then either randomly assigned to continued HLS or allow normal physical weight-bearing remobilization (HLS + R). Mice allowed normal cage activity throughout the experiment served as controls (GC). All mice were sacrificed 14-days following fracture with 4-8 mice (male and female) per treatment. Data analyzed by respective ANOVA with Tukey post-hoc (*p< 0.05; # p < 0.10)Male and female mice showed conserved and significant decreases in hindlimb callus bone formation from continued HLS versus HLS + R. Combining treatment groups regardless of mouse sex, histological analyses using staining on these same calluses demonstrated that HLS resulted in trends toward decreased cartilage cross-sectional area and increased osteoclast density in woven bone versus physically rehabilitated mice.In support of our hypothesis, physical remobilization increases callus bone formation following fracture compared to continued disuse potentially due to increased endochondral ossification and decreased bone resorption. In all, partial weight-bearing exercise immediately following fracture may improve callus healing compared to delayed rehabilitation regimens that are frequently used.

Clinical Study on the Treatment of Long Bone Fracture Non-Union with Extracorporeal Shock Wave Therapy Combined with Platelet-Rich Plasma

Objective: The objective of the study was to evaluate of the therapeutic efficacy of extracorporeal shock wave therapy (ESWT) combined with platelet-rich plasma (PRP) injection in patients with long bone fracture non-union. Material and Methods: A total of 36 patients identified with long bone fracture non-union treated from September 2020 to September 2023 were enrolled into this study. Employing a random number table method, they were randomly divided into three groups, with 12 cases in each group. Based on the treatment modality, the groups were categorized as the ESWT group, PRP group, and combination ESWT + PRP group. Routine radiographs and musculoskeletal ultrasound were obtained before treatment and at 3-, 6-, and 9-month post-treatment intervals to observe for bone callus formation and assess fracture line imaging scores with the aim to evaluate the treatment efficacy of each group. Results: With the extension of treatment time, the bone callus and fracture line imaging scores of the three groups gradually increased (P < 0.05). At 3-, 6-, and 9-month post-treatment, the scores of the ESWT combined with the PRP group were significantly better than those of the singular ESWT group and PRP group, and the differences were statistically significant (P < 0.05). Conclusion: Therapy with singular ESWT, singular PRP, and combination ESWT + PRP has demonstrated effective improvement in fracture healing for patients with long bone fracture non-union. The synergistic effects of combination therapy were more significant, surpassing the efficacy of singular ESWT or PRP applications. The combined use of ESWT and PRP represents a safe and promising alternative treatment for long-bone fracture non-union, making it a compelling choice in the context of fracture healing. Keywords: Extracorporeal shock wave therapy, Platelet-rich plasma, Non-union of fracture.

Local zinc treatment enhances fracture callus properties in diabetic rats.

The effects of locally applied zinc chloride (ZnCl2 ) on early and late-stage parameters of fracture healing were evaluated in a diabetic rat model. Type 1 Diabetes has been shown to negatively impact mechanical parameters of bone as well as biologic markers associated with bone healing. Zinc treatments have been shown to reverse those outcomes in tests of nondiabetic and diabetic animals. This study is the first to assess the efficacy of a noncarrier mediated ZnCl2 on bony healing in diabetic animals. This is a promising basic science approach which may lead to benefits for diabetic patients in the future. Treatment and healing were assessed through quantification of callus zinc, radiographic scoring, microcomputed tomography (µCT), histomorphometry, and mechanical testing. Local ZnCl2 treatment increased callus zinc levels at 1 and 3 days after fracture (p ≤ 0.025). Femur fractures treated with ZnCl2 showed increased mechanical properties after 4 and 6 weeks of healing. Histomorphometry of the ZnCl2 -treated fractures found increased callus cartilage area at Day 7 (p = 0.033) and increased callus bone area at Day 10 (p = 0.038). In contrast, callus cartilage area was decreased (p < 0.01) after 14 days in the ZnCl2 -treated rats. µCT analysis showed increased bone volume in the fracture callus of ZnCl2 -treated rats at 6 weeks (p = 0.0012) with an associated increase in the proportion of µCT voxel axial projections (Z-rays) spanning the fracture site. The results suggest that local ZnCl2 administration improves callus chondrogenesis leading to greater callus bone formation and improved fracture healing in diabetic rats.

Traumatic temporomandibular joint bony ankylosis in growing rats.

The pathogenesis of traumatic temporomandibular joint (TMJ) bony ankylosis remains unknown. This study aimed to explore the pathogenesis of traumatic TMJ bony ankylosis in a rat model. Twenty-four 3-week-old male Sprague-Dawley rats were used in this study. Excision of the whole disc, the fibrocartilage damage of the condyle and glenoid fossa, and narrowed joint space were performed in the left TMJ of the operation group to induce TMJ bony ankylosis (experimental side). The right TMJ underwent a sham operation (sham side). The control group did not undergo any operations. At 1, 4, and 8weeks postoperatively, rats of the operation group were sacrificed and TMJ complexes were evaluated by gross observation, Micro-CT, histological examinations, and immunofluorescence microscopy. Total RNA of TMJ complexes in the operation group were analyzed using RNA-seq. Gross observations revealed TMJ bony ankylosis on the experimental side. Micro-CT analysis demonstrated that compared to the sham side, the experimental side showed a larger volume of growth, and a considerable calcified bone callus formation in the narrowed joint space and on the rougher articular surfaces. Histological examinations indicated that endochondral ossification was observed on the experimental side, but not on the sham side. RNA-seq analysis and immunofluorescence revealed that Matrix metallopeptidase 13 (MMP13) and Runt-related transcription factor 2 (RUNX2) genes of endochondral ossification were significantly more downregulated on the experimental side than on the sham side. The primary pathways related to endochondral ossification were Parathyroid hormone synthesis, secretion and action, Relaxin signaling pathway, and IL-17 signaling pathway. The present study provided an innovative and reliable rat model of TMJ bony ankylosis by compound trauma and narrowed joint space. Furthermore, we demonstrated the downregulation of MMP13 and RUNX2 in the process of endochondral ossification in TMJ bony ankylosis.

Identification and characterization of NFATc1+ skeletal stem cells in bone regeneration.

Skeletal stem cells (SSCs) fuel adult bone with stemness resources to maintain homeostasis and support regeneration, which depends on the precise determination of the osteogenic lineage commitment of SSCs. In this study, using Cre-loxP reporter lineage tracking, we identified and characterized a population of NFATc1+ SSCs in bone regeneration. Pre-existing NFATc1+ SSCs are involved in early bone callus formation. Subsequently, these NFATc1+ SSCs produce osteolineage descendants in the subsequent stages of regeneration. The Ca2+-triggered transcriptional activity of NFATc1 constitutes the pre-imprinted memory of the trajectory to intrinsically orchestrate osteogenesis of SSCs. Inhibition of Ca2+/NFATc1 signaling in SSCs directly impairs osteogenesis and bone regeneration. In summary, our findings provide a mechanistic understanding of adult bone regeneration through the regulation of NFATc1+ SSCs.

Does the c.-14C>T Mutation in the IFITM5 Gene Provide Identical Phenotypes for Osteogenesis Imperfecta Type V? Data from Russia and a Literature Review

Osteogenesis imperfecta (OI) is a large group of genetically heterogeneous diseases resulting from decreased bone density and an abnormal microarchitecture, which are clinically manifested by abnormal bone fractures. A distinctive clinical feature of this group of diseases is the presence of spontaneous fractures and skeletal deformities. However, the clinical manifestations of different types of OI are characterized by marked polymorphism with variable severity of skeletal and extra-skeletal features. Previous studies have shown that a mutation (c.-14C>T) in the IFITM5 gene is responsible for autosomal dominant OI type V. However, the mutation has a variable expression pattern and marked clinical heterogeneity. In this study, a clinical and genetic analysis of 12 cases with molecularly confirmed OI type V from 12 unrelated families was performed. Significant clinical heterogeneity of the disease with the same molecular defect was detected. In six subjects (50%), there were no classic signs of OI type V (formation of a hyperplastic bone callus, calcification of the interosseous membrane and dislocation of the radial head). In all cases, the mutation occurred de novo.

Effect of Annular External Fixator-Assisted Bone Transport on Clinical Healing, Pain Stress and Joint Function of Traumatic Massive Bone Defect of Tibia.

Objective To investigate the effect of annular external fixator-assisted bone transport in the treatment of traumatic massive bone defect of tibia on clinical healing, pain stress, and joint function. Methods From January 2018 to November 2021, 146 patients with traumatic massive bone defect of tibia were selected as the research objects, and they were divided into observation group (annular external fixator-assisted bone transport, 71 cases) and control group (unilateral external fixator bone lengthening, 75 cases) according to different surgical methods. The therapeutic efficacy, fracture healing-related indexes, and postoperative range of motion of the knee joint were compared between the two groups. Callus healing was evaluated by Fernandez-Esteve callus score, and joint function was evaluated by Paley score, American Knee society score (AKSS), and Baird-Jackson ankle score. The changes of pain mediator (serum substance P (SP), neuropeptide Y (NPY), prostaglandin E2 (PGE2), and tumor necrosis factor-α (TNF-α)) and stress indexes (adrenocorticotropic hormone (ACTH), cortisol (COR), and nor Epinephrine (NE)) were observed before and after treatment in two groups. The incidence of postoperative complications was analyzed. Results There were no significant differences in total effective rate and bone lengthening between the two groups (P > 0.05). The bone healing time and callus formation time in the observation group were shorter than those in the control group, and the Fernandez-Esteve callus score was higher than that in the control group (P < 0.05). The levels of SP, NPY, PGE2, TNF-α, ACTH, COR, and NE in the observation group were lower than those in the control group (P < 0.05). AKSS and Baird-Jackson scores in the observation group after operation were higher than those in the control group (P < 0.05). There was no significant difference in the incidence of postoperative complications between the two groups (P > 0.05). Conclusion Annular external fixator-assisted bone transport can promote postoperative fracture healing, reduce pain stress level, and improve joint function of patients with traumatic massive bone defect of tibia.

BIOMECHANICAL AND PHYSIOLOGICAL PRINCIPLES APPLIED IN CHEST WALL RECONSTRUCTION ASSOCIATED WITH RIB FRACTURES

TYPE: Abstract TOPIC: Cardiothoracic Surgery PURPOSE: The aim of this study was to describe osseointegration of osteosynthesis material and risk of surgical intervention when biomechanical and physiological principles are applied in chest wall reconstruction (CWR). METHODS: All adult patients with pulmonary contusion, multiple rib fractures, flail chest, hemothorax or pneumothorax associated with rib fractures who underwent CWR between March 2012 and December 2016 in emergency department retrospectively included.Titanium clips pressure-fitted at 2 cm proximal and distal were used at each fracture site. Curvature of the clip was made to simulate the natural curvature of the costal arch. In all cases the vascular and nervous package was released. Postoperative follow-ups were obtained from medical records and the integration of the osteosynthesis material was assessed. RESULTS: The 60 patients were 37 men and 23 woman, average age of 44 years. Hospital stays between 7 and 16 days. At 30 days postoperative complications had been recorded such as respiratory insufficiency (n=2) and acute myocardial infarction (n=1).Osteointegration of the osteosynthesis material was found in 59 patients (98.3%) and 1 patient (1.6%) present refracture and mobilization of a titanium implant, for which it was surgery reintervened and the defect corrected CONCLUSIONS: In our study, we found a very high percentage of osseointegration when using the biomechanical principles in the techniques for CWR. CLINICAL IMPLICATIONS: The healing process near fracture sites relies in a correct immobilization,adequate vascularization and formation of bone callus and new bone therefore, by using titanium clips combined with different biomechanical principles they help this purpose by improving the conditions at the fracture site. DISCLOSURE: Nothing to declare. KEYWORD: CHEST WALL RECONSTRUCTION

β-type TiNbSn Alloy Plates With Low Young Modulus Accelerates Osteosynthesis in Rabbit Tibiae.

β-type TiNbSn Alloy Plates With Low Young Modulus Accelerates Osteosynthesis in Rabbit Tibiae.

Development of an ischemic fracture healing model in mice.

Background and purposeIn fracture healing, ischemia caused by vascular injuries, chronic vascular diseases, and metabolic comorbidities is one of the major risk factors for delayed union and non-union formation. To gain novel insights into the molecular and cellular pathology of ischemic fracture healing, appropriate animal models are needed. Murine models are of particular interest, as they allow to study the molecular aspects of fracture healing due to the availability of both a large number of murine antibodies and gene-targeted animals. Thus, we present the development of an ischemic fracture healing model in mice.Material and methodsAfter inducing a mild ischemia by double ligature of the deep femoral artery in CD-1 mice, the ipsilateral femur was fractured by a 3-point bending device and stabilized by screw osteosynthesis. In control animals, the femur was fractured and stabilized without the induction of ischemia. The femora were analyzed at 2 and 5 weeks after fracture healing by means of radiology, biomechanics, histology, and histomorphometry.ResultsThe surgically induced ischemia delayed and impaired the process of fracture healing. This was indicated by a lower Goldberg score, decreased bending stiffness, and reduced bone callus formation in the ischemic animals when compared with the controls.InterpretationWe introduce a novel ischemic femoral fracture healing model in mice, which is characterized by delayed bone healing. In future, the use of this model may allow both the elucidation of the molecular aspects of ischemic fracture healing and the study of novel treatment strategies.

Local Infiltrative Analgesia of Murine Femur Fractures In Vivo Does Not Inhibit Fracture Healing.

The opioid epidemic in the United States has forced care providers to seek out alternatives to narcotic analgesics. Physicians involved in trauma care, including orthopaedic trauma surgeons, often have patients requiring significant amounts of these medications, especially in the perioperative period, given the acuity and severity of their injuries. Modalities such as local infiltration of fractures with anesthetic agents during operative treatment may provide some benefit to this population by decreasing postoperative pain and narcotic usage. However, prior data suggest that these agents are chondrotoxic, which may impede secondary fracture healing. The purpose of this study was to investigate the hypothesis that local anesthetics decrease secondary bone healing and callus formation in stabilized murine femur fractures through chondrocyte apoptosis. Male C57BL/6 mice underwent intramedullary stabilization and fracture of bilateral femurs followed by immediate infiltration of the fracture site with local anesthetic agents. Femurs were dissected at 10- and 20-days post-fracture and evaluated by muCT and histological analysis. No significant differences were seen in callus size or mineralization between controls and fractures treated with a local anesthetic. When the callus was analyzed histologically, local anesthetic agents appeared to increase cartilage density. Therefore, infiltration of local anesthetics during operative treatment of fracture as part of a multimodal approach to pain control does not appear to significantly affect callus formation in a preclinical model, although subclinical molecular effects may be present. Local infiltrative analgesia with local anesthetics may be used as an adjunct for perioperative pain control during femur fracture surgery without a significant effect on secondary bone healing.

Electrospun composites of poly-3-hydroxybutyrate reinforced with conductive fillers for in vivo bone regeneration

The aim of this study was to investigate the biocompatibility and osteoinductive properties of fibrous scaffolds implanted in the bone tissue of white rats in vivo. The effect of various concentrations of conductive PANi (2 and 3 wt%) and rGO (0.2 and 1 wt%) in the PHB scaffolds on the reparative processes of bone callus formation in white rats was studied. On the 28th day after implantation, a histomorphological study of the preparations of the transverse section of the diaphysis of the femur of the implantation area was performed. The results of implantation tests in the femur revealed that all the studied scaffolds are biocompatible and the most pronounced stimulating effect on bone formation was observed for hybrid PHB scaffolds doped with 3 wt% PANi and 0.2 wt% rGO compared with pure PHB scaffolds, thus determining further prospects to study the osteoinductive features of hybrid PHB scaffolds.