Artificial intelligence models based on non-contrast chest CT for measuring bone mineral density

Objective To observe the value of artificial intelligence(AI)models based on non-contrast chest CT for measuring bone mineral density(BMD).Methods Totally 380 subjects who underwent both non-contrast chest CT and quantitative CT(QCT)BMD examination were retrospectively enrolled and divided into training set(n=304)and test set(n=76)at a ratio of 8∶2.The mean BMD of L1—L3 vertebrae were measured based on QCT.Spongy bones of T5—T10 vertebrae were segmented as ROI,radiomics(Rad)features were extracted,and machine learning(ML),Rad and deep learning(DL)models were constructed for classification of osteoporosis(OP)and evaluating BMD,respectively.Receiver operating characteristic curves were drawn,and area under the curves(AUC)were calculated to evaluate the efficacy of each model for classification of OP.Bland-Altman analysis and Pearson correlation analysis were performed to explore the consistency and correlation of each model with QCT for measuring BMD.Results Among ML and Rad models,ML Bagging-OP and Rad Bagging-OP had the best performances for classification of OP.In test set,AUC of ML Bagging-OP,Rad Bagging-OP and DL OP for classification of OP was 0.943,0.944 and 0.947,respectively,with no significant difference(all P>0.05).BMD obtained with all the above models had good consistency with those measured with QCT(most of the differences were within the range of Ax-G±1.96 s),which were highly positively correlated(r=0.910—0.974,all P<0.001).Conclusion AI models based on non-contrast chest CT had high efficacy for classification of OP,and good consistency of BMD measurements were found between AI models and QCT.

Artificial tiger bone powder for improving the quality of life in elderly patients with fracture

Objective: To investigate the application of artificial tiger bone powder on fracture healing time, wrist functional recovery and quality of life (QOL) in elderly patients with distal radius fracture. Methods: The study was a randomised controlled trials performed from January 2015 to December 2016 in a hospital. Elderly patients with distal radius fracture were divided into the treatment and the control groups by the random sealed envelope method. All patients were given splint or plaster fixation after manipulative reduction, and functional exercise, the treatment group was also given artificial tiger bone powder orally (trade name: Jintiange capsule), the control group was given an oral placebo in their appearance and usage identical with the treatment group. Prior to treatment and 6, 12 months after treatment, the wrist function was assessed by range of motion, including flexion-extension, radial-ulnar and pronation-supination, and the QOL was assessed by the Mos 36-item Short Form Health Survey. Each patient's fracture healing time was recorded. Results: Before treatment, there were no significant differences in wrist function and QOL between the two groups. At 6 and 12 months after treatment, the wrist function and QOL in the treatment group were better than those in the control group, the differences were statistically significant (P < 0.05). The fracture healing time in the treatment group was shorter than that of the control group, and the difference was statistically significant (P < 0.05). Conclusion: The early usage of artificial tiger bone powder for elderly patients with distal radius fracture can promote the healing of fracture, recovery of wrist joint function, and ultimately improve the QOL for elderly patients.

Autotransplantation of Teeth and the Reconstruction of Alveolar Bone Defects Using Artificial Bone: A Case Series

The aim of this study was to evaluate the outcome of autotransplantation or replantation of extracted teeth combining with reconstruction of alveolar bone defects in use of artificial bone grafting clinically and radiographically. This article presents a more useful and convenient method for repairing tooth and reconstruction of bone defecting with some interesting cases. Eleven patients (seven men and four women) in whom teeth with complete root formation were extracted and autotransplanted, the bone of receiving area was Insufficient. All transplanted teeth were stabilized with orthodontic wire and resin or 4-0 silk sutures;at the same time, artificial bone powder was filled. In 11 cases, the missing teeth were restored by autogenous teeth and the alveolar bone defect was restored by artificial bone, the improvement in the radiographic and clinical parameters strongly suggest that it may be a useful therapy to solve the problem of the missing teeth and alveolar bone insufficiency simultaneously. However, the risk of replacement root resorption remains.

The Construction and Investigation of PLGA Artificial Bone by Biomimetic Mineralization

To modify the surface property of poly lactide-co-glycolide （PLGA） by biomimetic mineralization to construct a new kind of artificial bone. PLGA films and 3-diamensional （3-D） porous scaffolds hydrolyzed in alkaline solution were minerilized in SBF for 14 days. The morphology and composition of the mineral grown on PLGA were analyzed with SEM, FTIR and XRD. The porosity of the scaffolds was detected by using the liquid displacement method. The compressive strength of the scaffolds was detected by using a Shimadzu universal mechanic tester. An obvious mineral coating was detected on the surface of films and scaffolds. The main compqnent of the mineral was carbonated hydroxyapatite （HA） similar to the major mineral component of bone tissues. The porosity of the un-mineralized and mineralized porous scaffolds was （84.86±8.52） % and （79.70 ± 7.70） % respectively. The compressive strength was 0. 784±0. 156 N/mm^2 in un-mineralized 3-D porous PLGA and 0. 858±0. 145 N/mm^2 in mineralized 3-D porous PLGA. There were no significant differences between the mineralized and un-mineralized scaffolds （P〉0, 05） in porosity and biomechanics. Biomimetic mineralization is a suitable method to construct artificial bone.

Macrophages in Degradation of Calcium Phosphate Compound Artificial Bone： An in vitro Study

The isolated mice peritoneal macrophages in degradation of calcium phosphate compound artificial bone - collagen/hydroxylapatite (CHA). hydroxylapatite (HA), beta-tricalcium phosphate (TCP) ceramics, have been studied by use of both Ca++, P concentration assay in cultured supernatant and scanning electron microscopy (SEM). The solubility of Ca++ . composition of materials increased more significantly when macrophages were inoculated than when macrophages were not seeded (P< 0.001), and it was shown that the ground materials were wrapped and phagocytized or resorbed extracellularly by macrophages under SEM, suggesting that macrophages could mediate the degradation of calcium phosphate compound artificial bone by phagocytizing and/or degrading extracellularly.

Experimental Study on Polymer Artificial Bone with HA Coated and Fiber Liners

Layers of ante-polymerized PMMA （ Polymethylmethacrylate ） ore manually smeared on both sides of carbon fiber and polyester fiber to a certain thickness. It was pre-solidified, stripped and cut for sterilization. Based on the results of a series of experiments, HA coated artificial bone is considered to be a non-senshizing, non- irritant, and non- toxic biomaterial for medical applications. The artificial bone has excellent mechanical and biological property. And it conforms to the national standard requirement. Safety analysis guarantees h a prosperous future of clinical application.

Development of an Artificial Finger-Like Knee Loading Device to Promote Bone Health

This study presents the development of an innovative artificial finger-like device that provides position specific mechanical loads at the end of the long bone and induces mechanotransduction in bone. Bone cells such as osteoblasts are the mechanosensitive cells that regulate bone remodelling. When they receive gentle, periodic mechanical loads, new bone formation is promoted. The proposed device is an under-actuated multi-fingered artificial hand with 4 fingers, each having two phalanges. These fingers are connected by mechanical linkages and operated by a worm gearing mechanism. With the help of 3D printing technology, a prototype device was built mostly using plastic materials. The experimental validation results show that the device is capable of generating necessary forces at the desired frequencies, which are suitable for the stimulation of bone cells and the promotion of bone formation. It is recommended that the device be tested in a clinical study for confirming its safety and efficacy with patients.

Mechanical Properties of a Vacuum-Sintered Apatite Body for Use as Artificial Bone

Regenerative artificial bone material and bone parts were fabricated using vacuum-sintered bodies of a “titanium medical apatite (TMA?)” that is formed by chemically connecting Ti oxide molecules to the reactive [Ca10 (PO4 )6 ] group of hydroxyapatite (HAp). Sintering at temperatures of 1273 - 1773 K caused this TMA sintered bodies to recrystallize and form a varying mix of α-TCP (tricalcium phosphate), β-TCP and Perovskite-CaTiO3 phases. The Perovskite crystals proved to be quite stable and hard, forming a uniform distribution of similarly sized fibers in all directions under vacuum sintering, but an irregular distribution and size when sintered in the presence of oxygen. Complete recrystallization was achieved by vacuum sintering at temperatures in excess of 1473 K. In particular, TMA vacuum-sintered bodies at 1573 K are given the maximum value;a Vickers hardness of 400, a bending strength of 43 MPa, a compressive strength of 270 MPa and a density of approximately 2300 kg/m3 was achieved that closely corresponds to that of compact bone or a tooth. As these TMA bodies could also be cut into various forms, they are considered a promising biomaterial for use as artificial bone in the regeneration of natural bone, or to provide reinforcement of bone junctions in dental and orthopedic surgery.

Artificial dermis combined with skin grafting for the treatment of hand skin and soft tissue defects and exposure of bone and tendon

BACKGROUND The recovery time of hand wounds is long,which can easily result in chronic and refractory wounds,making the wounds unable to be properly repaired.The treatment cycle is long,the cost is high,and it is prone to recurrence and disability.Double layer artificial dermis combined with autologous skin transplantation has been used to repair hypertrophic scars,deep burn wounds,exposed bone and tendon wounds,and post tumor wounds.AIM To investigate the therapeutic efficacy of autologous skin graft transplantation in conjunction with double-layer artificial dermis in treating finger skin wounds that are chronically refractory and soft tissue defects that expose bone and tendon.METHODS Sixty-eight chronic refractory patients with finger skin and soft tissue defects accompanied by bone and tendon exposure who were admitted from July 2021 to June 2022 were included in this study.The observation group was treated with double layer artificial dermis combined with autologous skin graft transplantation(n=49),while the control group was treated with pedicle skin flap transplantation(n=17).The treatment status of the two groups of patients was compared,including the time between surgeries and hospital stay.The survival rate of skin grafts/flaps and postoperative wound infections were evaluated using the Vancouver Scar Scale(VSS)for scar scoring at 6 mo after surgery,as well as the sensory injury grading method and two-point resolution test to assess the recovery of skin sensation at 6 mo.The satisfaction of the two groups of patients was also compared.RESULTS Wound healing time in the observation group was significantly longer than that in the control group(P<0.05,27.92±3.25 d vs 19.68±6.91 d);there was no significant difference in the survival rate of skin grafts/flaps between the two patient groups(P>0.05,95.1±5.0 vs 96.3±5.6).The interval between two surgeries(20.0±4.3 d)and hospital stay(21.0±10.1 d)in the observation group were both significantly shorter than those in the control group(27.5±9.3 d)and(28.4±17.7 d),respectively(P<0.05).In comparison to postoperative infection(23.5%)and subcutaneous hematoma(11.8%)in the control group,these were considerably lower at(10.2%)and(6.1%)in the observation group.When comparing the two patient groups at six months post-surgery,the excellent and good rate of sensory recovery(91.8%)was significantly higher in the observation group than in the control group(76.5%)(P<0.05).There was also no statistically significant difference in two point resolution(P>0.05).The VSS score in the observation group(2.91±1.36)was significantly lower than that in the control group(5.96±1.51),and group satisfaction was significantly higher(P<0.05,90.1±6.3 vs 76.3±5.2).CONCLUSION The combination of artificial dermis and autologous skin grafting for the treatment of hand tendon exposure wounds has a satisfactory therapeutic effect.It is a safe,effective,and easy to operate treatment method,which is worthy of clinical promotion.

An investigation on plasma spraying with artificial bone powder and bonding characteristics of coating

Artificial bone powder is satisfactorily deposited onto the surface of synthetic metal arthrosis(Co-Cr-Mo) with plasma spraying process. Factors influencing the quality of coating are investigated. Bond of artificial bone powder coating sprayed with different parameters is measured. and the coatings are anlyzed with metallographic examination and electron probe analysis. Experiments show that artificial bone powder coating sprayed onto synthetic metal arthrosis with satisfactory bond strength can be obtained by manipulating plasma spraying.

Study on the physical properties and chemical compositions of artificially synthesized coral hydroxyl apatite (CHA) bone

To develop synthesized coralline hydroxyl apatite (CHA) bone graftsubstitute and measure its physical and chemical characteristics. Methods: The CHA bone graft substitute was synthesized from natural mineral―coralline through hydrothermal exchange process. This process was designed and developed independently by the authors. Its physical and chemical characteristics have been determined and studied using various techniques including Scanning Electron Microscopy (SEM), electron microscope image processing, scanning electron microscope energy spectrography; chemical analysis, ICP-AES, X-ray diffraction, etc. Clinical trials have been conducted. Results: Independently developed CHA bone graft-substitute is white in color; its porosity is 25.87%–53.58%, which is approximate to that of human bones and original coral. It is larger than 3–4 in hardness by Mohs hardness scale and the compressive strength ranges from 4.87 to 12.31 MPa. The chemical compositions of the CHA are 53.13%–64.09% CaO and 35.52%–46.48% P2O5. CaO/P2O5 is 1.143–1.804. ICP-AES analysis detected twenty-four trace elements including Pb, Co, Ni, Ba, Mn, Cr, Th, V, Cu, Ti, K, Mo, Zn, Mg, Nb, Be, Sc, Al, Sr, Na, Li, etc. Ca, P, K, Na, Al and Sr are relatively high while the rest are less than n–n×10-6, which is acceptable by human body. The REE level in the CHA bone measured by ICP-MS is 1.433×10-9–2.212×10-9, which is within the acceptable range for human beings. Conclusions: The process of synthesized CHA bone graft-substitute is an innovated independently developed method and concept. Its color, porosity and chemical composition are similar to those of human bones; therefore it has very good biocompatibility and excellent conductivity. Sixty clinical cases have proved that CHA bone graft-substitute has a strong bone-forming ability, no toxicity, no side effect, and better sacralization. It is a fine substitute for bone transplantation.

Study on β-TCP Coated Porous Mg as a Bone Tissue Engineering Scaffold Material

Three-dimensional honeycomb-structured magnesium （Mg） scaffolds with interconnected pores of accurately controlled pore size and porosity were fabricated by laser perforation technique. Biodegradable and bioactiveβ- tricalcium phosphate （β-TCP） coatings were prepared on and the biodegradation mechanism was simply evaluated the porous Mg to further improve its biocompatibility, in vitro. It was found that the mechanical properties of this type of porous Mg significantly depended on its porosity. Elastic modulus and compressive strength similar to human bones could be obtained for the porous Mg with porosity of 42.6%-51%. It was observed that the human osteosarcoma cells （UMR106） were well adhered and proliferated on the surface of the β- TCP coated porous Mg, which indicates that theβ-TCP coated porous Mg is promising to be a bone tissue engineering scaffold material.

Biological Evaluation of α-TCP/TTCP Composite Bone Cement

tricalcium phosphate(α TCP)/tetracalcium phosphate(TTCP) composite bone cement had good hydration characteristic.In our system,α TCP/TTCP powder mixture was mixed with water at a powder/liquid (P/L) ratio of 1.50g·mL -1 .The setting time could be adjusted,the maximum compressive strength was 45.36MPa,and the hydration product was hydroxyapatite (HAP).In vitro biological simulated experiments indicate that α TCP/TTCP bone cement has α certain dissolubility.The hardened product is mainly HAP after soaking in simulated body fluid (SBF) for 10 weeks.The results of in vitro test and animal experiments and SEM analyses show that no local or general toxicity response,no muscle stimulation,no haemolysis,no cruor,no inflammatory reaction and no exclusion response are caused by α TCP/TTCP cement, which can be contributed to bone tissue spreading and impinging.α TCP/TTCP cement hydrated and hardened continually in vivo.The materials fused with host bone together with implanting time prolonging.Therefore,it is believed that α TCP/TTCP composite bone cement has a high biocompatibility and bioactivity,a certain biodegradation and good osteogenesis as well.

Osteogenesis Capacity of a Novel BMP/α-TCP Bioactive Composite Bone Cement

To improve the osteogenesis ability of a-tricalcium phosphate (α-TCP) bone cement, a novel BMP/ α-TCP composite bone cement was prepared. By measuring the setting time and compressive strength, the hydration characteristic of bone cement was evaluated. Animal experiments including histological observation, radiographic investigation as well as digital image analyses reveal the difference of osteogenesis ability among BMP,a-TCP bone cement and BMP/α-TCP composite bone cement. Results show that α-TCP bone cement possesses excellent hydration and setting properties as well as high mechanical property. Comparison experiments show that BMP/ α-TCP composite bone cement has a stronger osteogenesis ability. The gross observation of the implant site does not exhibit any inflammation or necrosis. Histological analyses reveal that the material has good osteointegration with host bone, and new bone formation is detected within the materials, which are degrading. Strong osteogenesis ability of the composite is due to not only the excellent osteoconductive potential but also the osteoinductive potential contributed by active BMP releasing and the material degradation. Large skull defect could be well-healed by filling BMP/α-TCP composite bone cement. This novel material proves itself to be an absorbable and bioactive bone cement with an osteogenesis ability. Key words α-tricalcium phosphate (α-TCP) - bone morphogenetic proteins (BMP) - bone cement - osteogenesis - osteoinductivity - bone tissue engineering Funded by 863 Hi-Tech Research and Development Program of China (2002AA326080) and the Fund for Outstanding Young Teacher of the Education Ministry of China(2002123)

基于Citespace对人工智能在骨创伤研究的可视化分析

背景:人工智能在医疗领域的发展日益迅速,在骨创伤领域的应用研究不断增多。文章旨在通过文献计量学分析,分析近年来人工智能在骨创伤领域中的研究热点,并预测未来的研究趋势。目的:总结人工智能技术在骨创伤领域的应用发展历程、研究现状、热点和未来发展趋势,以期为今后的研究提供新的见解。方法:选择Web of Science核心集数据库中,时间跨度设为自建库至2023年8月,检索人工智能、机器学习、深度学习应用于骨创伤相关的文献420篇。通过人工筛选,导出与文章相关的文献共202篇,采用Citespace软件进行国家、机构、被引期刊和引文分析等的合作和关键词的共现等可视化分析。结果与结论:①分析筛选后纳入的202篇文献,总体发文量呈上升趋势,且在未来研究潜力巨大。研究中心性最高和发文量排名第一的国家均为美国。加州大学(美国)是发文量最多的研究机构。②人工智能在骨创伤研究中最常用的前5个关键词是深度学习、人工智能、骨密度、机器学习、诊断,中心性最高的关键词为骨密度,关键词数量最多的为深度学习。③共被引频次前10位的参考文献分别从多个方面介绍了人工智能技术应用于骨创伤领域诊断的可行性研究,其中8篇涉及骨关节损伤与深卷积神经网络,1篇涉及深度学习在CT检查中检测骨质疏松从而预防脆性骨折,1篇通过人工智能识别皮肤纹理变的特征应用于骨的特征性识别的相关性研究。④今后,人工智能的研究热点将主要集中在骨关节创伤和骨质疏松引发的骨折特异性研究上,未来研究趋势主要集中在提升人工智能算法的性能上,使用人工智能新技术对骨损伤进行精准划分和快速高效诊断,尤其是针对复杂和隐匿性骨折的诊断,通过建立有限元分析模型,实现对骨创伤的更加标准化评估。

Multiscale engineered artificial compact bone via bidirectional freeze-driven lamellated organization of mineralized collagen microfibrils

Bone,renowned for its elegant hierarchical structure and unique mechanical properties,serves as a constant source of inspiration for the development of synthetic materials.However,achieving accurate replication of bone features in artificial materials with remarkable structural and mechanical similarity remains a significant challenge.In this study,we employed a cascade of continuous fabrication processes,including biomimetic mineralization of collagen,bidirectional freeze-casting,and pressure-driven fusion,to successfully fabricate a macroscopic bulk material known as artificial compact bone(ACB).The ACB material closely replicates the composition,hierarchical structures,and mechanical properties of natural bone.It demonstrates a lamellated alignment of mineralized collagen(MC)microfibrils,similar to those found in natural bone.Moreover,the ACB exhibits a similar high mineral content(70.9%)and density(2.2 g/cm^(3))as natural cortical bone,leading to exceptional mechanical properties such as high stiffness,hardness,and flexural strength that are comparable to those of natural bone.Importantly,the ACB also demonstrates excellent mechanical properties in wet,outstanding biocompatibility,and osteogenic properties in vivo,rendering it suitable for a broad spectrum of biomedical applications,including orthopedic,stomatological,and craniofacial surgeries.

Polymethylmethacrylate bone cements and additives: A review of the literature

Polymethylmethacrylate(PMMA) bone cement technology has progressed from industrial Plexiglass administration in the 1950 s to the recent advent of nanoparticle additives. Additives have been trialed to address problems with modern bone cements such as the loosening of prosthesis, high post-operative infection rates, and inflammatory reduction in interface integrity. This review aims to assess current additives used in PMMA bone cements and offer an insight regarding future directions for this biomaterial. Low index(< 15%) vitamin E and low index(< 5 g) antibiotic impregnated additives significantly address infection and inflammatory problems, with only modest reductions in mechanical strength. Chitosan(15% w/w PMMA) and silver(1% w/w PMMA) nanoparticles have strong antibacterial activity with no significant reduction in mechanical strength. Future work on PMMA bone cements should focus on trialing combinations of these additives as this may enhance favourable properties.

Molecular mechanisms of intermuscular bone development in fish:a review

Intermuscular bones(IBs)are slender linear bones embedded in muscle,which ossify from tendons through a process of intramembranous ossification,and only exist in basal teleosts.IBs are essential for fish swimming,but they present a choking risk during human consumption,especially in children,which can lead to commercial risks that have a negative impact on the aquaculture of these fish.In this review,we discuss the morphogenesis and functions of IBs,including their underlying molecular mechanisms,as well as the advantages and disadvantages of different methods for IB studies and techniques for breeding and generating IB-free fish lines.This review reveals that the many key genes involved in tendon development,osteoblast differentiation,and bone formation,e.g.,scxa,msxC,sost,twist,bmps,and osterix,also play roles in IB development.Thus,this paper provides useful information for the breeding of new fish strains without IBs via genome editing and artificial selection.

3D打印PLLA/β-TCP复合人工骨及组织相容性研究

目的基于3D打印技术制备新型可生物降解的左旋聚乳酸(poly L-lactic acid,PLLA)/β-磷酸三钙(β-tricalcium phosphate,β-TCP)复合人工骨,并对其性能及组织相容性进行研究,探究其作为体内组织工程骨材料的可行性。方法扫描电镜观察3D打印的PLLA/β-TCP复合人工骨微观形貌、动静态疲劳试验机检测力学强度、水银孔率计及密度法测量其孔隙率。复合人工骨培养骨髓间充质干细胞(C3H10)后观察细胞状态以评价其细胞相容性。用复合人工骨浸提液培养C3H10细胞并观察细胞的分化情况。将未培养细胞的PLLA/β-TCP复合人工骨植入新西兰大白兔臀肌肌袋内1个月、2个月及3个月后行组织切片观察其组织相容性。结果扫描电镜下可见PLLA/β-TCP具备多孔结构,接种培养的C3H10细胞在PLLA/β-TCP复合人工骨中大量黏附、伸展生长。PLLA/β-TCP复合人工骨的弹性模量最高为(21.1±3.4)MPa,抗弯强度最高为(9.5±2.3)MPa,孔隙率为(51±3)%。复合人工骨浸提液培养C3H10细胞7d及21d后进行碱性磷酸酶及茜素红染色阳性,提示复合人工骨中存在成骨诱导分化成分。PLLA/β-TCP复合人工骨植入体内后早期出现纤维包囊,包囊内见少量的中性粒细胞及淋巴细胞浸润。后期纤维包裹逐渐消失,人工骨与周围组织结合密切,界限模糊,仅见少许淋巴细胞。人工骨植入实验结果符合国际及国家医疗器械的植入后局部反应试验标准。结论 3D打印PLLA/β-TCP复合多孔人工骨具备优良的力学强度,良好的细胞相容性、骨诱导性及组织相容性,是一种理想的组织工程骨材料。