Bone Composition Research Articles

UTE MRI technical developments and applications in osteoporosis: a review

Osteoporosis (OP) is a metabolic bone disease that affects more than 10 million people in the USA and leads to over two million fractures every year. The disease results in serious long-term disability and death in a large number of patients. Bone mineral density (BMD) measurement is the current standard in assessing fracture risk; however, the majority of fractures cannot be explained by BMD alone. Bone is a composite material of mineral, organic matrix, and water. While bone mineral provides stiffness and strength, collagen provides ductility and the ability to absorb energy before fracturing, and water provides viscoelasticity and poroelasticity. These bone components are arranged in a complex hierarchical structure. Both material composition and physical structure contribute to the unique strength of bone. The contribution of mineral to bone’s mechanical properties has dominated scientific thinking for decades, partly because collagen and water are inaccessible using X-ray based techniques. Accurate evaluation of bone requires information about its components (mineral, collagen, water) and structure (cortical porosity, trabecular microstructure), which are all important in maintaining the mechanical integrity of bone. Magnetic resonance imaging (MRI) is routinely used to diagnose soft tissue diseases, but bone is “invisible” with clinical MRI due to its short transverse relaxation time. This review article discusses using ultrashort echo time (UTE) sequences to evaluate bone composition and structure. Both morphological and quantitative UTE MRI techniques are introduced. Their applications in osteoporosis are also briefly discussed. These UTE-MRI advancements hold great potential for improving the diagnosis and management of osteoporosis and other metabolic bone diseases by providing a more comprehensive assessment of bone quantity and quality.

Low rate of healing and high incidence of complications in benign pediatric bone tumors treated with synthetic calcium sulfate-calcium phosphate bone graft.

Synthetic calcium sulfate-calcium phosphate bioceramic composite has been developed as a material for bone grafting; however, the literature is limited on outcomes of benign bone tumors treated with bone grafting. This study aims to investigate the outcomes of benign pediatric bone tumors treated with a calcium sulfate-calcium phosphate composite bone graft. A retrospective review at a tertiary pediatric hospital with benign bone tumors treated with curettage and bone grafting with a calcium sulfate-calcium phosphate synthetic bone graft from 2008-2018 was included. Minimum follow-up was 6 months. Twenty-seven patients met inclusion criteria with a mean age of 10.3 ± 4.5 years and follow-up was 37.2 ± 22.3 months. Diagnoses were unicameral bone cysts (n = 16) and aneurysmal bone cysts (n = 11). Pathologic fracture was present in 48% (13/27) of patients on admission. All patients were treated using synthetic bone grafts and 37% (10/27) with internal fixation. Following index treatment, 96% (26/27) had resolution of pain and returned to full activity at 13.4 ± 10.7 weeks. Complications occurred in 33% (9/27) of patients; one developed chronic hip pain resulting in decreased physical activity, seven had a tumor recurrence without fracture, and one had tumor recurrence with pathologic fracture. Revision surgery was required in 26% (7/27) of cases. Per the modified Neer outcomes rating system, 52% of patients had a healed bone lesion, 4% had a healing lesion with a bone defect, and 44% had a persistent/recurrent cyst. Children with benign bone tumors treated with curettage and bone grafting using a calcium sulfate-calcium phosphate composite had a high incidence of complications and revision surgery. IV.

In vivo bone regeneration performance of hydroxypropyl methylcellulose hydrogel-based composite bone cements in ovariectomized and ovary-intact rats: a preliminary investigation

The objective of this study is to fabricate and develop hydroxypropyl methylcellulose (HPMC) hydrogel (HG)-based composite bone cements with incorporation of hydroxyapatite (HA), beta-tricalcium phosphate (β-TCP), and with/without polymethylmethacrylate (PMMA) for vertebroplasty. For animal study, twenty female Wister rats (250–300 g, 12 weeks of age) were divided into four groups including a two non-ovariectomy (NOVX) groups and two ovariectomy (OVX)-induced osteoporosis groups. Two prepared biocomposites including HG/β-TCP/HA and HG/β-TCP/HA/PMMA were injected into the tibial defects of both OVX and NOVX rats for evaluating in vivo osteogenesis after 12 weeks. Micro-computed tomography and histological analysis using hematoxylin and eosin (H&E) and Masson's trichrome stains of the two composite cements implanted into the tibial defects of OVX and NOVX rats revealed enhanced bone regeneration potential. However, no statistically significant differences were noted among the groups based on new bone formation, demonstrating that the injected composite cements showed similar osteogenesis effects in both OVX and NOVX rats. These findings suggest that the newly developed composite bone cement composed of HG, β-TCP, HA and/or PMMA may be a promising and professional tool for treating osteoporotic and non-osteoporotic vertebral fractures.

Prediction of hip fracture by high-resolution peripheral quantitative computed tomography in older Swedish women.

The socioeconomic burden of hip fractures, the most severe osteoporotic fracture outcome, is increasing and the current clinical risk assessment lacks sensitivity. This study aimed to develop a method for improved prediction of hip fracture by incorporating measurements of bone microstructure and composition derived from high-resolution peripheral quantitative computed tomography (HR-pQCT). In a prospective cohort study of 3028 community-dwelling women aged 75 to 80, all participants answered questionnaires and underwent baseline examinations of anthropometrics and bone by dual x-ray absorptiometry (DXA) and HR-pQCT. Medical records, a regional x-ray archive, and registers were used to identify incident fractures and death. Prediction models for hip, major osteoporotic fracture (MOF), and any fracture were developed using Cox proportional hazards regression and machine learning algorithms (neural network, random forest, ensemble, and XGBoost). In the 2856 (94.3%) women with complete HR-pQCT data at 2 tibia sites (distal and ultra-distal), the median follow-up period was 8.0years, and 217 hip, 746 MOF, and 1008 any type of incident fracture occurred. In Cox regression models adjusted for age, BMI, clinical risk factors (CRF), and femoral neck bone mineral density (FN BMD) the strongest predictors of hip fracture were tibia total volumetric BMD and cortical thickness. The performance of the Cox regression-based prediction models for hip fracture was significantly improved by HR-pQCT (time-dependent AUC; area under receiver operating characteristic curve at 5years of follow-up 0.75 [0.64-0.85]), compared to a reference model including CRFs and FN BMD (AUC = 0.71 [0.58-0.81], p<.001) and a FRAX risk score model (AUC = 0.70 [0.60-0.80], p<.001). The Cox regression model for hip fracture had a significantly higher accuracy than the neural network-based model, the best-performing machine learning algorithm, at clinically relevant sensitivity levels. We conclude that the addition of HR-pQCT parameters improves the prediction of hip fractures in a cohort of older Swedish women.

Current Evidence on the Impact of Diet, Food, and Supplement Intake on Breast Cancer Health Outcomes in Patients Undergoing Endocrine Therapy

Background/Objectives: The most common type of breast cancer (BRC) in women is estrogen/progesterone receptor positive. First-line treatment includes endocrine therapy, either with aromatase inhibitors or tamoxifen to reduce estrogen levels. Among the side effects produced by this treatment, aromatase inhibitor-induced arthralgia is the most common, affecting the patients’ overall health and quality of life (QoL). The objectives here were to evaluate interventions examining the impact of modified diets, supplements, and/or some food components on health outcomes in BRC patients undergoing endocrine therapy. Methods: The literature search was performed in PubMed, Scopus, and Web of Science from June 2024, as well as manually, through the end of November 2024. The search was limited to studies of women diagnosed with estrogen/progesterone-receptor-positive BRC with selected articles reporting interventions with diet, food, or supplement intake and examining the relevant health outcomes. Studies not focusing on BRC patients undergoing endocrine therapy or not including specific health outcomes were excluded. Results: The search uncovered 1028 studies; after the removal of duplicates, abstracts, and irrelevant studies, 53 were closely examined, with 26 evaluated and presented here. The outcomes were changes in bone and body composition, cardiovascular disease risks, inflammation, and QoL. Conclusions: The examined evidence suggests that adherence to dietary patterns such as the Mediterranean or a low-fat diet, and a higher intake of fruits and vegetables were beneficial for various outcomes. Additionally, supplementation with some foods/components (dried plum, red clover) contributed to improving/maintaining bone and body composition, especially in overweight/obese patients. Supplementation with vitamin D or omega-3 improved lipid and angiogenic parameters and QoL. Although these results are promising, the effects of each supplement/food cannot be summarized due to the diverse nature of study designs, patients, and supplement dosages. Further studies are needed to explore the effects of specific nutritional interventions (including the newest, like fasting-mimicking diets and whole-grain cereal diets) on various health outcomes in BRC survivors during endocrine therapy, and to derive universal recommendations.

The Microbial Diversity and Biofilm Characteristics of d-PTFE Membranes Used for Socket Preservation: A Randomized Controlled Clinical Trial

Background: Understanding microbial colonization on different membranes is critical for guided bone regeneration procedures such as socket preservation, as biofilm formation may affect healing and clinical outcomes. This randomized controlled clinical trial (RCT) investigates, for the first time, the microbiome of two different high-density polytetrafluoroethylene (d-PTFE) membranes that are used in socket preservation on a highly molecular level and in vivo. Methods: This RCT enrolled 39 participants, with a total of 48 extraction sites, requiring subsequent implant placement. Sites were assigned to two groups, each receiving socket grafting with a composite bone graft (50% autogenous bone, 50% bovine xenograft) and covered by either a permamem® (group P) or a Cytoplast™ (group C). The membranes were removed after four weeks and analyzed using scanning electron microscopy (SEM) for bacterial adherence, qPCR for bacterial species quantification, and next-generation sequencing (NGS) for microbial diversity and composition assessment. Results: The four-week healing period was uneventful in both groups. The SEM analysis revealed multispecies biofilms on both membranes, with membranes from group C showing a denser extracellular matrix compared with membranes from group P. The qPCR analysis indicated a higher overall bacterial load on group C membranes. The NGS demonstrated significantly higher alpha diversity on group C membranes, while beta diversity indicated comparable microbiota compositions between the groups. Conclusion: This study highlights the distinct microbial profiles of two d-PTFE membranes during the four-week socket preservation period. Therefore, the membrane type and design do, indeed, influence the biofilm composition and microbial diversity. These findings may have implications for healing outcomes and the risk of infection in the dental implant bed and should therefore be further explored.

Long-Term Stability and Osteogenic Activity of Recycled Polysulfone-Calcium Silicate Bone Implants In Vitro.

Environmental protection issues have received widespread attention, making material recycling increasingly important. The upcycling of polysulfone (PSF) medical waste, recognized as a high-performance plastic with excellent mechanical properties, deserves promotion. While PSF is suitable for use as an orthopedic implant material, such as internal fixation, its osteogenesis capabilities must be enhanced. Mechanical stability, particularly over the long term, is a significant concern for bone implants in load-bearing applications. This study recycled PSF medical waste to create bone composites by incorporating osteogenic calcium silicate (CaSi) at three different contents: 10%, 20%, and 30%. We evaluated the phase, morphology, weight loss, and three-point bending strength of the PSF-based composites after they were soaked in dynamic simulated body fluid (SBF) at pH levels of 7.4 and 5.0 for up to 12 months. Human mesenchymal stem cells (hMSCs) were utilized to assess the osteogenic activity of these composites. Our findings revealed that, while the bending strength of PSF-based composites declined with prolonged exposure to SBF, the dissolution of CaSi particles led to a manageable weight loss of about 4% after 12 months, regardless of pH 7.4 or 5.0. Importantly, the incorporation of CaSi into the PSF matrix exhibited a positive effect on the attachment and proliferation of hMSCs. The levels of alkaline phosphatase (ALP) and calcium deposits directly correlated with the CaSi content, indicating superior osteogenic activity. Considering biostability and osteogenic ability, the 20% CaSi-PSF composite demonstrated promise as a candidate for load-bearing implant applications.

Comparative analysis of solvent-based and solvent-free (melting) methods for fabricating 3D-printed polycaprolactone-hydroxyapatite composite bone scaffolds: physicochemical/mechanical analyses and in vitro cytocompatibility.

The study conducts a comparative analysis between two prominent methods for fabricating composites for bone scaffolds-the (solid) solvent method and the solvent-free (melting) method. While previous research has explored these methods individually, this study provides a direct comparison of their outcomes in terms of physicochemical properties, cytocompatibility, and mechanical strength. We also analyse their workflow and scalability potentials. Polycaprolactone (PCL) and hydroxyapatite (HA) composites were prepared using solvent (chloroform) and melting (180°C) methods, then 3D-printed using an extrusion-based 3D printer to fabricate scaffolds (8 × 8 × 4mm). Rheology, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), accelerated degradation, mechanical/compression test, wettability/contact angle, live/dead assay, and DNA quantification (Picogreen) assays were evaluated. The study finds that scaffolds made via the solid solvent method have higher mechanical strength and degradation rate as compared to those from the melting method, while both methods ensure adequate cytocompatibility and homogenous hydroxyapatite distribution, supporting their use in bone tissue engineering. This research investigates the utility of chloroform as a solvent for PCL composite in a direct comparison with the melting method. It also highlights the differences in workflows between the two methods and their scalability implications, emphasizing the importance of considering workflow efficiency and the potential for automation in scaffold fabrication processes for bone tissue engineering applications.

Volumetric measurement of manually drawn segmentations in cone beam computed tomography images of newly formed bone after sinus floor augmentation with bovine-derived bone substitutes.

Precise volumetric measurement of newly formed bone after maxillary sinus floor augmentation (MSFA) can help clinicians in planning for dental implants. This study aimed to introduce a novel modular framework to facilitate volumetric calculations based on manually drawn segmentations of user-defined areas of interest on cone-beam computed tomography (CBCT) images MATERIAL & METHODS: Two interconnected networks for manual segmentation of a defined volume of interest and dental implant volume calculation, respectively, were used in parallel. The volume data of dental implant manufacturers were used for reference. The efficacy of this framework was demonstrated through practical applications for collecting CBCT data from patients after MSFA with the same quantity of two different bovine-derived bone substitutes: xenohybrid composite bone (Group I, n = 10) and hydroxyapatite (Group II, n = 10). The study was approved by the central Ethical Review Board of the federal state of Lower Austria (approval number: GS4-EK-4/451-2021). The volumes were measured immediately (T1) and 6 months (T2) after MSFA and before insertion of the dental implant. All measurements were analyzed for inter- and intravariability. P-values of >0.05 were obtained from the t-test analysis RESULTS: The manual delineation of Group II (n = 10) was easier than that of Group I (n = 10) due to the visual contrast of the CBCT scan. The mean volume was 861.65 ± 290.02 mm³ at T1 and 875.9 ± 288.96 mm³ at T2. This shows a moderate dispersion around the mean value, which indicates variability of the analyzed data DISCUSSION: The proposed network may be useful for the development of computer-based diagnostic systems for assessing the success of MSFA with bone replacement materials. The volumetric stability achieved with the two bone replacement materials were comparable.

Effects of Polyvinyl Alcohol – Hydroxyapatite Composite Ceramic on Calvarial Defects with Critical Size in Rat Models

Introduction: Biodegradable composite biomaterials are essential in healthcare, effectively tackling numerous complex challenges. Bone reconstruction is a surgical procedure aimed at remedying segmental bone loss, which is notably complicated and often fails to heal properly. A novel bone graft substitute incorporating polyvinyl alcohol (PVA) and synthetic hydroxyapatite (HA) has been developed and is tested in vivo in calvarial defect models of rat. The present study aimed to evaluate the bone regeneration potential of PVA – HA composite bone graft. Materials and methods: A total of 24 adult male Wistar rats aged 12-15 weeks with an average weight of 150 grams were used in the current study. A 4 mm full-thickness critical-size defect was created on the parietal bone and filled with the pre-sized graft material. Radiography, micro-computed tomography, scanning electron microscopy, histology, and serum biochemical parameters, including alkaline phosphatase and acid phosphatase activity, were utilized to evaluate the healing potential of the graft material. The animals were observed for twelve weeks. An immediate postoperative dorsoventral view of the skull was exposed at day zero and subsequent radiographs were taken periodically at weeks 2, 4, 8, and 12 in a group including 24 animals. Results: Immediate post-operative radiographs revealed the radiolucent nature of the graft material. Throughout the healing process, it was observed that the graft remained in position and was intact. The values of serum biochemical parameters alkaline phosphatase and acid phosphatase activity) were haphazard throughout the observation period. In the 8th week, signs of progressive degradation of the graft material and bone regeneration could be seen, particularly on radiography, micro-CT scanning electron microscopy, and histologic examination. Conclusion: It is concluded that the test graft material successfully accelerated bone regeneration and completely integrated with the host bone at week 12 of the experiment in the rat model.

Comparison Between Nano-Hydroxyapatite/Beta-Tricalcium Phosphate Composite and Autogenous Bone Graft in Bone Regeneration Applications: Biochemical Mechanisms and Morphological Analysis.

It was assumed that only autogenous bone had appropriate osteoconductive and osteoindutive properties for bone regeneration, but this assumption has been challenged. Many studies have shown that synthetic biomaterials must be considered as the best choice for guided bone regeneration. The objective of this work is to compare the performances of nanohydroxyapatite/β-tricalcium phosphate (n-HA/β-TCP) composite and autogenous bone grafting in bone regeneration applications. The composite was characterized by scanning electron microscopy (SEM) and used as an allograft in bone defects formed in adult Wistar rats. The bone defects in the dorsal cranium were grafted with autogenous bone on one side and the n-HA/β-TCP composite on the other. Histomorphometry evaluation via different staining methods (Goldner trichrome, PAS, and Sirius red) and TRAP histochemistry were performed. Immunohistomorphometries of OPN, Cathepsin K, TRAP, acid phosphatase, VEGF, NFκ-β, MMP-2, MMP-9, and TGF-β were carried out. The RT-PCR method was also applied to to RANK-L, Osteocalcine, Alcaline Phosphatase, Osterix, and Runx2. The results showed that for all morphometric evaluations with the different staining methods, histochemistry, and immunohistochemistry, VEGF and NFκ-β were higher in the n-HA/β-TCP composite group than in the autogenous bone graft group. The RT-PCR markers were higher in the autogenous bone group than in the n-HA/β-TCP composite group. The n-HA/β-TCP composite exhibited enhanced cell-matrix interactions in bone remodeling, higher adhesion, proliferation, and differentiation, and increased vascularization. These results suggest that the n-HA/β-TCP composite induces faster bone formation than autogenous bone grafting.

Investigation of Antibiotic‐Releasing Biodegradable Composite Bone Cements for Treating Experimental Chronic Maxillofacial Bone Infection

ABSTRACTChronic osteomyelitis of the maxillofacial bones (i.e., jaw bones) is a persistent infection that requires effective treatment. Because systemic antibiotics seldom reach necrotic areas to remove bone infection, local antibiotic carriers such as antibiotic‐loaded bone cement can be tried. It is critical to assess the biosafety and efficacy of two new antibiotic‐loaded biodegradable composite bone cements for treating chronic mandibular osteomyelitis, and their drug eluting efficiency and other relevant aspects prior to clinical trial. The physico‐mechanical properties, and drug release capacity of the cements were determined to be suitable for in vivo application. After inducing chronic osteomyelitis with Staphylococcal strains in 30 female rabbit mandibles, bioactive glass composite cement (0.5 g) and biphasic calcium phosphate composite cement (0.5 g) were implanted in 18 defects (nine/test group) for 84 days to compare the therapeutic efficacy with traditional therapy (control, debridement plus antibiotics in nine defects) using microscopic, micrographic, and radiological examination. Antibiotic concentrations in bone (vancomycin: 34.7–53.2 μg/g, tobramycin: 2.1–2.87 μg/g) after 21 days of installation for both cements were sufficient to eradicate pathogens without causing adverse events. In vivo tests suggest that cement groups outperformed (p &lt; 0.05) traditional therapy in terms of infection clearance and osteoconduction. The gross histologic and micrographic scores of biphasic calcium phosphate composite cement (10.33 ± 0.58 and 8.33 ± 1.53, respectively) indicated that the cement barely surpassed (p &gt; 0.05) the other composite cement (12.67 ± 1.53 and 10.0 ± 1.0, respectively). These findings emphasize the potential of antibiotic loaded composite cements as an effective treatment option for chronic maxillofacial osteomyelitis, offering a safer and more efficient alternative to traditional therapy.

Characterization of akermanite (AKT) and zirconia-infused PMMA bone cement composite with superior physicochemical, mechanical, and bioactive properties for enhanced orthopaedic performance

ABSTRACT The development of advanced bone cements is critical for enhancing the performance and longevity of orthopaedic implants. This study introduces a combination synthesis method for producing akermanite (AKT-Ca2MgSi2O7) ceramics and commercial zirconia (ZrO2) bioceramics. This study aims to improve the material’s mechanical strength, bioactivity, and biocompatibility by the incorporation of bioceramics into the polymethyl methacrylate (PMMA) matrix. The PMMA matrix ensures appropriate handling characteristics and setting times suitable for clinical applications. Characterization studies reveal that the composite achieves an optimal balance between bioactivity and mechanical performance. The results indicated that the AKT/PMMA/ZrO2 composite bone cements that were produced exhibited a substantially lower polymerization temperature than pure PMMA. Additionally, they maintained high compressive strength (~105 MPa) and optimal setting times (9–14 minutes). The bioactivity assessment, through simulated body fluid immersion tests, indicates a layer of hydroxyapatite is formed on the composite surface within 7 days, confirming its osteointegration potential. Furthermore, the composite exhibits excellent biocompatibility, with in vitro assays showing over 90% cell viability after 24 hours of culture. Scanning electron microscopy and X-ray diffraction analyses confirm the homogeneous distribution of akermanite and zirconia throughout the PMMA matrix, contributing to ensuring the uniform mechanical characteristics and bioactivity of the composite material.

Bone quality analysis of the mandible in alcoholic liver cirrhosis: Anatomical, microstructural, and microhardness evaluation.

Alcoholic bone disease has been recognized in contemporary literature as a systemic effect of chronic ethanol consumption. However, evidence about the specific influence of alcoholic liver cirrhosis (ALC) on mandible bone quality is scarce. The aim of this study was to explore microstructural, compositional, cellular, and mechanical properties of the mandible in ALC individuals compared with a healthy control group. Mandible bone cores of mаle individuаls with ALC (n = 6; age: 70.8 ± 2.5 yeаrs) and age-matched healthy controls (n = 11; age: 71.5 ± 3.8 yeаrs) were obtаined postmortem during аutopsy from the edentulous аlveolаr bone in the mandibular first molаr region аnd the mаndibulаr аngulus region of each individual. Micro-computed tomogrаphy wаs used to аssess bone microstructure. Analyses based on quаntitаtive bаckscаttered electron microscopy included the characterization of osteon morphology, osteocyte lаcunаr properties, and bone mаtrix minerаlizаtion. Composition of bone minerаl аnd collаgen phаses was assessed by Rаmаn spectroscopy. Histomorphometry wаs used to determine cellulаr аnd tissue chаrаcteristics of bone specimens. Vickers microhardness test was used to evaluate cortical bone mechanical properties. The ALC group showed higher closed cortical porosity (volume of pores thаt do not communicаte with the sаmple surfаce) (p = 0.003) and smaller lacunar area in the trabecular bone of the molar region (p = 0.002) compared with the Control group. The trabecular bone of the angulus region showed lower osteoclast number (p = 0.032) in the ALC group. There were higher carbonate content in the buccal cortex of the molar region (p = 0.008) and lower calcium content in the trabecular bone of the angulus region (p = 0.042) in the ALC group. The cortical bone showed inferior mechanical properties in the ALC cortical bony sites (p < 0.001), except for the buccal cortex of the molar region (p = 0.063). There was no significant difference in cortical thickness between the groups. Bone quality is differentially altered in ALC in two bony sites and compartments of the mandible, which leads to impaired mechanical properties. Altered mandible bone tissue characteristics in patients with ALC should be considered by dental medicine professionals prior to oral interventions in these patients. Knowledge about mandible bone quality alterations in ALC is valuable for determining diagnosis, treatment plan, indications for oral rehabilitation procedures, and follow-up procedures for this group of patients.

Nutritional and toxicological evaluation of Jojoba (Simmondisa chinensis) oil meal in the complete feed of rabbits

Fourty New Zealand white rabbits were randomly allotted to four equal dietary treatments consisting of complete mixed rations (16% CP; 15% CF) without (T0) and with 5 (T1), 15 (T2) and 25 (T3) per cent jojoba (Simmodsin chinensis) oil meal to study the toxicity as well as bone and meat characteristics. Supplementation of jojoba oil meal caused absolute mortality and the extent of mortality followed the dose response pattern. Fifty per cent of mortality rate was documented in T3 as early as 3rd week of experiment and at the end of 3rd week all experimental animals succumbed to death while no mortality recorded in control group. Chemical composition of meat and bone indicated significantly lower crude protein and ether extract contents in treated rabbits. Autopsy of rabbits which died in jojoba oil meal incorporated complete feed showed mild to severe dilated and congested mesenteric blood vessels and enlarged liver and kidney. Toxicopathological changes include hepatocellular swelling, bile duct hyperplasia, glomerular nephritis and thyroiditis indicative of simmondsin toxicity in rabbits due to jojoba oil meal.

Management of Bone Defects and Complications After Bone Tumor Resection Using Ilizarov Method.

Ilizarov technology is highly effective in addressing complex orthopedic challenges. This study aims to describe our experience with distraction osteogenesis in managing bone tumors in the lower extremity, focusing on composite bone defects and associated complications. A retrospective clinical study was conducted to analyze patients with primary bone tumors who underwent distraction osteogenesis using the Ilizarov method from 2010 to 2020. Some young children received epiphyseal distraction and bone transport as part of their sarcoma surgical treatment. Additionally, external fixation, bone transport, or limb lengthening were employed to address complex postoperative complications associated with bone tumors. The clinical outcomes assessed included the patient's general information, the location of bone defects, the length of bone repair, the status of bone healing, and limb function. Eleven patients were followed up for an average of 66 months (range, 24-132 months). The average length of repaired bone defects was 13 cm (range, 2.5-32 cm). The cohort comprised three females and eight males, with ages at presentation ranging from 6 to 42 years (mean, 18 years). The sites of involvement included the distal femur (n = 4), femoral diaphysis (n = 3), proximal tibia (n = 2), and the distal tibia (n = 2). Nine patients were diagnosed with osteosarcoma, while one presented with Ewing's sarcoma and another with a giant cell tumor of bone. Three young children were successfully treated with epiphyseal stretching; however, one patient experienced treatment failure. Additionally, seven patients underwent external fixation to address complex postoperative complications, including infection, bone defects, and limb shortening. At the last follow-up, with the exception of one failure, the average Musculoskeletal Tumor Society (MSTS) limb function scores for the remaining 10 patients were 25 (range, 21-30). Three months post-fixator removal, the Asociación Latinoamericana de Oncología (ASAMI) bone score was rated as excellent in 63.6% (7/11) of patients, whereas the ASAMI function score was excellent in 36.4% (4/11) and good in 54.5% (6/11) of cases. The Ilizarov method demonstrates some clinical value in the resection and reconstruction of bone tumors, as well as in the management of postoperative complications associated with such tumors.

Breaking the Mould: Comparing 3D-Printed and Composite Bone Models in Orthopaedic Training.

Background and aim Synthetic composite bone models (reinforced solid foam) have become the standardised material used in practical orthopaedic education. However, with discussions regarding whether composite foam truly replicates human bone, there has been a drive to explore other available models. Three-dimensional (3D) printing has risen in both popularity and availability, providing a new option in the creation of anatomically accurate bone models. We designed a pilot study to assess whether a new formulation of synthetic bone provides the same tactile feedback that is essential for training purposes. Method Orthopaedic trainees of various grades across two London hospital trusts were invited to participate in a distal radius fixation workshop. As part of the workshop, trainees were asked to complete the following three tasks on the two different models: Kirschner-wire driving, pilot hole drillingand screw insertion. Participants were blinded in this trialand not informed which model was made via 3D printing or the conventional composite bone. Following completion, participants provided feedback on tactile feedback for each task on each model. Results Twenty-three orthopaedic trainees participated in the workshop, with overall majority agreement in all clinical skills that the 3D-printed model provided better tactile feedback. Three-dimensional models were rated superior in K-wire driving (mean score 7.39 vs 4.82; p<0.001) and pilot hole drilling (7.87 vs 4.96; p<0.001), with no significant difference in screw insertion. Qualitative feedback from testers noted a more anatomical representation of the 3D-printed bone, in addition to an overall better representation of the corticomedullary junction. Conclusion Overall, 3D printed models provide a new high-fidelity and sustainable option when seeking bone models for modern-day orthopaedic training. At present composite bone remains the standard for workshops. However, with the growing availability of 3D-printing models, and as supported by this study, they crucially provide the medium for future orthopaedic surgeons to learn and gain confidence.

Enhanced biological activity of ACPs/cc/cs/PVA composite bone cement: a study on degradation, mineralization, and bone repair properties

The application of calcium phosphate cement in bone repair is often limited by its restricted degradation and mineralization capabilities. Here, we developed a novel composite material integrating amorphous calcium phosphates (ACPs) and calcium citrate (CC) to enhance biological activity. The composite was combined with powdered chitosan (CS) and liquid polyvinyl alcohol (PVA) to formulate the ACPs/CC/CS/PVA bone cement. We investigated the influence of varying PVA concentrations (0.3%, 0.6%, 1.0%, and 1.5%) on the cement’s setting time, hydrophilicity, compressive strength, pH, calcium release rate, and degradation rate. We find the ACPs/CC/CS/PVA bone cement demonstrates favorable injectability and anti-washout characteristics within the PVA concentration range of 0.3–1.5%. An elevated PVA concentration is correlated with enhanced anti-washout properties and improved compressive strength, reaching 42.8 MPa, which is essential for maintaining mechanical stability at the defect site. Additionally, the 1.5% PVA cement formulation ensures an adequate calcium ion concentration (6.5–9.5 mg/L) for the beginning of bone repair. Furthermore, in vivo animal studies have confirmed the biocompatibility of the ACPs/CC/CS/PVA bone cement. Controlled release of Ca2+ and PO4 3− ions from ACPs is suggested to facilitate osteoconduction and osteogenesis, highlighting the material’s prospect in bone repair applications.

The Evaluation of Mechanical Properties of Commercial Composite Bones and 3D-Printed Bones Produced Using the CJP Technology

Cadaver bones and artificial bones are utilized to perform preoperative studies and education purposes. Cadaver bones are hard to find, require ethical permissions, and have infection hazards. Therefore, commercial artificial bones are preferred in practice. Nonetheless, since these commercial alternatives are standardly produced in an average size and geometry, it is almost impossible to adapt them to a specific surgical simulation. In addition, these artificial bones have relatively high costs, which limits their accessibility. On the other hand, ColorJet printing (CJP), one of the three-dimensional printing technologies, offers a rapid and cost-effective alternative. However, whether the printed 3D-printed models can mechanically comply with artificial bones is unclear. In this study, 3D-printed bones and artificial commercial composite bones were compared in terms of mechanical properties. Compression tests were applied over 14 printed and 14 composite bones using the ISO 5833 standard. Mechanical properties including stress-strain, load to failure, and elastic modulus were calculated, and these results were compared using the two-sample independent t-test, which is one of the statistical analysis methods. Consequently, there was no significant difference between the bone models in terms of stress and failure load values (p

Comorbidity of frontotemporal dementia in the bone evidenced as, gender‐specific alterations in the bone microarchitecture, composition, and biomechanical properties observed in MAPT P301S transgenic mouse model

Comorbidity of frontotemporal dementia in the bone evidenced as, gender‐specific alterations in the bone microarchitecture, composition, and biomechanical properties observed in MAPT P301S transgenic mouse model