Effect of domestic porous tantalum modified by osteogenic induction factor slow-release system on function of MG63 cells / 中国组织工程研究

BACKGROUND:Previous research by the research team found that domestically produced porous tantalum is beneficial for early adhesion and proliferation of MG63 cells,and can be used as a scaffold material for bone tissue engineering. OBJECTIVE:To investigate the effect of domestic porous tantalum modified by osteogenic induction factor slow-release system on the adhesion,proliferation,and differentiation of MG63 cells. METHODS:Osteogenic induction factor slow-release system was constructed by adding 15%volume fraction of osteogenic factor solution to poly(lactic-co-glycolic-acid)gel.The passage 3 MG63 cells were inoculated on a porous tantalum surface(control group),porous tantalum surface coated with poly(lactic-co-glycolic-acid)copolymer gel(gel group),and porous tantalum surface coated with osteoblastic induction factor slow-release system(slow-release system group),and co-cultured for 5 days.The surface cytoskeleton of the material was observed by phalloidine staining.Cell proliferation was detected by flow cytometry.Western blot assay and RT-qPCR were used to detect the protein and mRNA expressions of type Ⅰ collagen,osteopontin,and RUNX-2 on the surface cells of the material. RESULTS AND CONCLUSION:(1)Phalloidine staining showed that MG63 cells adhered to and grew on the surface and inside of the three groups of porous tantalum,and the matrix secreted by the cells covered the surface of the material.(2)Flow cytometry showed that the cell proliferation in the slow-release system group was faster than that in the control group and the gel group(P<0.05).(3)Western blot assay and RT-qPCR showed that the protein and mRNA expressions of type Ⅰ collagen,osteopontin,and RUNX-2 in the slow-release system group were higher than those in the control group and gel group(P<0.05).(4)The results showed that the domestic porous tantalum modified by the osteogenic induction factor slow-release system was beneficial to the adhesion,proliferation,and differentiation of MG63 osteoblasts.

Curative effects of 3D printed microporous titanium (tantalum) prosthesis in reconstruction of large segmental bone defects caused by lower extremity osteomyelitis / 中华创伤骨科杂志

Objective:To evaluate the curative effects of 3D printed microporous titanium (tantalum) prosthesis in reconstruction of large segmental bone defects caused by lower extremity osteomyelitis.Methods:A retrospective study was conducted to analyze the clinical data of 18 patients who had been treated for large segmental bone defects caused by lower extremity osteomyelitis between January 2020 to May 2022 at Department of Orthopaedics, The 920th Hospital of Joint Logistics Support Force. There were 10 males and 8 females with an age of (45.3±14.1) years. The defects were at the left side in 13 cases and at the right side in 5 cases, at the femur in 11 cases and at the tibia in 7 cases. The duration of osteomyelitis was 1.0 (1.0, 3.5) years. The length of bone defects was 8.35 (6.50, 9.84) cm. Their bone defects were repaired by an individually 3D printed microporous titanium (tantalum) prosthesis after operative removal of osteomyelitis lesions. The wound healing was observed after surgery. The clinical efficacy was comprehensively evaluated by the Paley grading for bone defect healing, visual analog scale (VAS), lower extremity functional scale (LEFS), and imaging examination.Results:The postoperative follow-up period for the 18 patients was (12.2±0.3) months. Wound infection occurred 2 months after surgery in one patient who was treated with Ilizarov bone transfer after removal of the microporous titanium prosthesis. The remaining 17 patients had good postoperative wound healing. At the last follow-up, the 18 patients had a VAS pain score of 2.0(1.0, 4.0) points, significantly lower than the preoperative one [(6.1±2.3) points], and a LEFS score of 54.00(34.50, 69.25) points, significantly higher than the preoperative one [18.50(9.00, 26.50) points] ( P<0.05). At the last follow-up, according to the Paley grading, the bone union was rated as excellent in 16 patients, as good in 1 patient and as poor in 1 patient. The integration of femoral fractures with 3D printed microporous titanium prostheses was fine. Conclusion:In reconstruction of large segmental bone defects caused by lower extremity osteomyelitis, implantation of a 3D printed microporous titanium (tantalum) prosthesis is feasible and effective, not only reducing pain but also restoring the limb function.

Flap combined with 3D printed microporous tianium(tantalum)prosthesis in the treatment of lower extremity soft tissue defect with large bone defect / 中华显微外科杂志

Objective:To investigate the effect of flap combined with 3D printed microporous titanium(tantalum)prosthesis in the treatment of lower extremity soft tissue defect with large bone defect.Methods:From January 2019 to December 2020, 2 patients with large soft tissue defects on dorsal foot together with large metatarsal bone defect and 4 patients with soft tissue defects of calf with large tibial bone defect were treated. The areas of soft tissue defect were 5.0 cm×8.0 cm-15.0 cm×10.0 cm. The length of the bone defect were 3.8 cm to 7.0 cm, 5.75 cm in average. In the first stage, metatarsal bone defect or tibial bone defect was filled with vancomycin blended bone cement, meanwhile, soft tissue defect was repaired with anterolateral femoral flap(ALTF) with vascular anastomosis in 2 cases of feet, and local fascia flap was trans-positioned in 4 cases of lower extremity defects. The sizes of repairing flap were 6.0 cm×8.5 cm-16.0 cm×11.0 cm. Two to 7 months after the initial surgery, the customer designed microporous titanium prostheses were used(5 cases with microporous titanium and 1 with microporous tantalum) to repair the bone defects. The wound healing, the integration of metatarsal and tibial fractures with 3D printed microporous titanium(tantalum) prostheses, and the walking condition were observed after surgery. The follow-up lasted from 6 to 25 months, with an average of 12.7 months.Results:The wound healing in 5 patients was good. The patients stood on the foot in 2 months after surgery, started to walk with the assistance of crutch in 3 months after surgery, and took walk without assistance in 5-6 months after surgery. Good osseous integration were achieved. One diabetic patient had infection of foot wound 3 months after surgery. After removal of microporous titanium prosthesis and replacement of vancomycin blended interstitial substance of bone cement, the wound healed and the patient resumed walking.Conclusion:It is an effective method to encourage the patients to take early ambulation after the surgery for lower extremity soft tissue defect with large bone defect that was repaired by a flap and 3D printed microporous titanium(tantalum)prosthesis. Further observations are required to investigate the long-term efficacy, and the reduction of prosthesis infection rate requires further exploration.

Influencing factors and biological property of novel biomedical materials: Porous silicon carbide coated with bioactive tantalum / 中国组织工程研究

BACKGROUND: Porous silicon carbide has excellent physical and chemical properties and can be used to repair complex shapes and long weight-bearing bone defects, but it has no biological activity and cannot promote bone remodeling and integration. OBJECTIVE: A tantalum (Ta) coating was deposited on the surface of the porous silicon carbide scaffold to evaluate its biological activity. METHODS: The chemical vapor deposition method was used to deposit a Ta coating on the surface of the porous silicon carbide scaffold. The optimal experimental parameters were explored by setting different gas reaction flow rates and temperatures. The Ta coating was prepared with the best experimental parameters to test the mechanical properties of porous Ta. Human osteoblasts were co-cultured with the Ta coating specimens, and were observed by scanning electron microscopy after 3 and 7 days of cultivation. RESULTS AND CONCLUSION: (1) After the optimization of experimental parameters, the best experimental conditions were controlled as follows: deposition temperature of 1 050 °C, hydrogen flow rate of 180 mL/min and chlorine flow rate of 100 mL/min. (2) The compressive strength of the Ta coated specimen was (61.4±3.2) MPa; the yield strength was (45.8±2.9) MPa; and the elastic modulus was 4.8 GPa. (3) Scanning electron microscopy demonstrated that after 3 days of co-cultivation, a large number of cells adhered to the surface of the porous silicon carbide scaffold that is coated with Ta and the porous structure. Some of the cells protruded from the pseudopod and were connected to each other. After 7 days of co-cultivation, the cell protrusions fused to form a sheet covering the surface of the porous Ta. In the porous structure, the cells protruded from the pseudopods, cross-linked to each other across the pores, secreted in the matrix, and coated the microparticle structure, gradually spreading in the pores. (4) The results show that the Ta coating on the surface of porous silicon carbide scaffold has good mechanical properties and biological activity.

Comparison of tantalum and titanium (Alloy) as orthopedic materials: Physical and chemical indexes, antibacterial and osteogenic ability / 中国组织工程研究

BACKGROUND: Tantalum and titanium (alloy) are the most widely employed metallic biomaterials in orthopedics. Tantalum is especially focused because of its excellent corrosion resistance and osteointegration. However, whether tantalum is better than titanium (alloy) as orthopedic materials is still in dispute. OBJECTIVE: To review the comparative studies on the biological performances of tantalum and titanium (alloy) and analyze the possible causes of the similarities and differences of biocompatibility of tantalum and titanium (alloy) materials in vivo and in vitro. METHODS: A computer-based search of CNKI, Wanfang and PubMed database was performed for articles relating to the comparative studies on the biological performances of tantalum and titanium (alloy) published until January 2020. The search words were “tantalum” in title and “titanium” in title or abstract, i.e., (tantalum[Title])) AND (titanium[Title/Abstract]). RESULTS AND CONCLUSION: Among the comparative studies on the biological performances of tantalum and titanium (alloy), two viewpoints were primarily involved according to the results from clinical follow-up, animal tests, and cellular experiments. One is that tantalum is superior to titanium (alloy) with better osteogenesis and bone formation and stronger antibacterial activity, while the other one is that tantalum has similar osteogenesis and bone formation and antibacterial activity to titanium (alloy). The primary reason responsible for this divergence is that the fabrication method and the surface chemistries, topographical structures or pore structures are different between the employed tantalum and titanium (alloy).

A inconfidência e insubordinação de Tântalo e suas reverberações no corpo político / The inconfidence and insubordination of Tantalus and its reverberations in the politial body / La incofidencia e insubordinación de Tántalo y sus reverberaciones em el cuerpo político

Este artigo propõe relacionar a trajetória e tragédia do mito grego Tântalo às conjunturas históricas, ressaltando o papel de destaque do corpo na construção da sociedade. Se alimenta de referências filosóficas, principalmente de Friedrich Wilhelm Nietzsche e de Arthur Schopenhauer e literárias de Franz Kafka e Augusto dos Anjos para poder instaurar um olhar sobre o corpo enquanto instrumento reflexivo e, por conseguinte, refém das barbáries corporais e psicológicas na história.

This article proposes to relate the trajectory and tragedy of the Greek myth Tantalus to the historical conjunctures, emphasizing the prominent role of the body in the construction of the society. It feeds on philosophical references, especially from Friedrich Nietzsche and Arthur Schopenhauer and from literary works by Franz Kafka and Augusto dos Anjos, in order to establish a look at the body as a reflexive instrument and, therefore, a hostage to the corporal and psychological barbarism in history.

Este artículo propone relacionar la trayectoria y tragedia del mito griego Tántalo a las coyunturas históricas, resaltando el papel destacado del cuerpo en la construcción de la sociedad. Se alimenta de referencias filosóficas, principalmente de Friedrich Wilhelm Nietzsche y de Arthur Schopenhauer y literarias de Franz Kafka y Augusto de los Ángeles para poder instaurar una mirada sobre el cuerpo como instrumento reflexivo y, por consiguiente, rehén de las barbarie corporales y psicológicas en la historia.

Early clinical effects of severe acetabular bone defects with 3D technology assisted tantalum augment / 中华骨科杂志

Objective@#To investigate the early clinical effects of tantalum augment assisted with 3D technology in treating acetabular bone defects of Paprosky type III in revision total hip arthroplasty (THA).@*Methods@#From May 2013 to July 2017, a total of 16 patients (18 hips) undergoing revision THA were retrospectively analyzed, including 11 males and 5 females aged 58.06±8.29 years (range 44-69 years). There were 3 cases with infective loosening and 15 cases with aseptic loosening, 13 cases with Paprosky IIIA type bone defects and 5 cases with IIIB type bone defects. 3D technology was used for precise planning before operation. The tantalum augment and cup were used to repair acetabular bone defects during operation. Cup anteversion, abduction angle, ratio of the lateral and contralateral vertical distance of the center of rotation, ratio of the lateral and contralateral horizontal distance of the center of rotation and femoral offset were measured preoperatively and postoperatively. The percentages of hips located in Lewinnek safe zone were calculated preoperatively and postoperatively. Postoperative radiographic evidence of loosening and Harris score were collected at the end of the follow-up.@*Results@#The percentage of the hips located in Lewinnek safe zone increased from 22% (4/18) preoperatively to 61% (11/18) postoperatively. The mean anteversion of the operative side was 11.99°±6.91° (range 1.71°-26.36°) postoperatively. The mean abduction angle of the operative side was 44.91°±5.93° (range 35.6°-56.0°). The mean ratio of the lateral and contralateral vertical distance of the center of rotation was 1.10±0.20 (range 0.87-1.62). The mean ratio of the lateral and contralateral horizontal distance of the center of rotation was 1.00±0.18 (range 0.69-1.46) and the mean ratio of the lateral and contralateral femoral offset was 1.01±0.66 (range 0.51-3.56). All the patients were followed-up for an average of 27.72±12.18 months (range 14-53 months). No complications, such as periprosthetic joint infection, dislocation or aseptic loosening, were observed in all patients. The mean Harris score was 77.28±4.80 (range 65-85) at 6 months postoperatively and 80.9±5.2 (range 69-89) at the end of the follow-up.@*Conclusion@#Using tantalum augmentassisted with 3D technology to re construct Paprosky type III severe bone defects of the hip can increase the accuracy of the acetabular cup positioning. The short-term outcomes are satisfying and no early prosthetic loosening was observed.

Early clinical effects of severe acetabular bone defects with 3D technology assisted tantalum augment / 中华骨科杂志

Objective To investigate the early clinical effects of tantalum augment assisted with 3D technology in treating acetabular bone defects of Paprosky type Ⅲ in revision total hip arthroplasty (THA).Methods From May 2013 to July 2017,a total of 16 patients (18 hips) undergoing revision THA were retrospectively analyzed,including 11 males and 5 females aged 58.06±8.29 years (range 44-69 years).There were 3 cases with infective loosening and 15 cases with aseptic loosening,13 cases with Paprosky ⅢA type bone defects and 5 cases with ⅢB type bone defects.3D technology was used for precise planning before operation.The tantalum augment and cup were used to repair acetabular bone defects during operation.Cup anteversion,abduction angle,ratio of the lateral and contralateral vertical distance of the center of rotation,ratio of the lateral and contralateral horizontal distance of the center of rotation and femoral offset were measured preoperatively and postoperatively.The percentages of hips located in Lewinnek safe zone were calculated preoperatively and postoperatively.Postoperative radiographic evidence of loosening and Harris score were collected at the end of the follow-up.Results The percentage of the hips located in Lewinnek safe zone increased from 22％ (4/18) preoperatively to 61％ (11/18) postoperatively.The mean anteversion of the operative side was 11.99°± 6.91° (range 1.71°-26.36°) postoperatively.The mean abduction angle of the operative side was 44.91°±5.93° (range 35.6°-56.0°).The mean ratio of the lateral and contralateral vertical distance of the center of rotation was 1.10±0.20 (range 0.87-1.62).The mean ratio of the lateral and contralateral horizontal distance of the center of rotation was 1.00±0.18 (range 0.69-1.46) and the mean ratio of the lateral and contralateral femoral offset was 1.01±0.66 (range 0.51-3.56).All the patients were followed-up for an average of 27.72± 12.18 months (range 14-53 months).No complications,such as periprosthetic joint infection,dislocation or aseptic loosening,were observed in all patients.The mean Harris score was 77.28±4.80 (range 65-85) at 6 months postoperatively and 80.9±5.2 (range 69-89) at the end of the follow-up.Conclusion Using tantalum augmentassisted with 3D technology to reconstruct Paprosky type Ⅲ severe bone defects of the hip can increase the accuracy of the acetabular cup positioning.The shortterm outcomes are satisfying and no early prosthetic loosening was observed.

Effect of bone morphogenetic protein-7 combined with porous tantalum on chondrogenic differentiation and function of bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND: The establishment of coculture system combined with physical factors and scaffold materials and the Induction of cytokines have become the focus of chondrogenlc differentiation of bone marrow mesenchymal stem cells. OBJECTIVE: To observe the effect of bone morphogenetic protein 7 combined with porous tantalum on chondrogenlc differentiation of bone marrow mesenchymal stem cells. METHODS: Bone marrow mesenchymal stem cells of Sprague-Dawley rats (provided by Beijing Huafukang Biology) were Isolated and cultured. Group Intervention: (1) in the experimental group, porous tantalum tablet was added, while In the control group, porous tantalum tablet was not added. At 5 days after culture, cell growth on the surface of porous tantalum tablet was observed by phalloidin staining. At 1, 3,5, and 7 days after culture, CCK-8 method was used to detect cell proliferation. (2) Group A was added with chondrocyte Inducer; group B with chondrocyte Inducer and bone morphogenetic protein 7; group C with domestic porous tantalum material and chondrocyte Inducer; group D with domestic porous tantalum material and chondrocyte Inducer and bone morphogenetic protein 7. At 7,14 and 21 days after culture, the levels of type II collagen, SRY type high mobility group protein and matrix metalloproteinase-13 secreted by cells In each group was detected by ELISA. Western blot assay was used to detect the expression of type II collagen, SRY type high mobility group protein and matrix metalloproteinase-13. This study was approved by the Animal Experimental Ethics Committee of North China University of Science and Technology. RESULTS AND CONCLUSION: (1) The phalloidin staining results showed that bone marrow mesenchymal stem cells grew well on and around the porous tantalum surface. (2) At 3 and 5 days after culture, the proliferation of bone marrow mesenchymal stem cells was slower In the experimental group than in the control group (P 0.05). (3) At 7,14 and 21 days, the expression of type II collagen and SRY high mobility group protein Increased gradually among groups A, B, C and D (P 0.05). At 21 days, there was no significant difference among groups A, B, C and D (P > 0.05). (4) Western blot assay showed that at 7,14 and 21 days after culture, the expression level of type II collagen and SRY high mobility group protein Increased gradually In groups A, B, C and D (P 0.05). (5) The results showed that bone morphogenetic proteln-7 combined with domestic porous tantalum could Induce cartilage differentiation of bone marrow mesenchymal stem cells, facilitate the expression of type II collagen and SRY high mobility group protein, and Inhibit the expression of matrix metalloproteinase-13.

Porous tantalum coated with RGD polypeptide can activate the integrin/focal adhesion kinase signaling pathway of MG63 cells / 中国组织工程研究

BACKGROUND: The compounding of RGD polypeptide on the surface of the material can induce the expression of osteoblast integrin gene, promote the adhesion of osteoblasts to the surface of biomaterials and differentiate into mature cells, and promote the formation of new bone. OBJECTIVE: To analyze the effect of domestic porous tantalum modified by RGD polypeptide on integrin/focal adhesion kinase signaling pathway in MG63 cells. METHODS: Porous tantalum material modified by RGD polypeptide was prepared. MG63 cells were inoculated on the surface of porous tantalum and porous tantalum materials modified with RGD polypeptide. MG63 cells cultured alone were used as the blank group. When cultured for 1, 3, 5, and 7 days, the cell proliferation was detected by the CCK-8 method. At 1, 3, and 5 days, the cell growth status was observed under an inverted microscope. At 3, 5 days of culture, cell adhesion was observed with scanning electron microscope. At 5 days of culture, RT-PCR and western blot assay were used to detect type I collagen and integrin β1 and focal adhesion kinase expression. RESULTS AND CONCLUSION: (1) The cell proliferation of the RGD modified group cultured at 3, 5, and 7 days was faster than that of the porous tantalum group and the blank group (P 0.05). (2) Observation by an inverted phase contrast microscope showed that the cells of the porous tantalum group and the RGD modified group were attached to the edge of the material when cultured for 1 day, and the number of cells gradually increased with the extension of the culture time. The number and density of cells in the RGD modified group were better than that of the porous tantalum group. (3) Observation by scanning electron microscope showed that cells adhered to the surface of the porous tantalum group and RGD modified group after 3 days of culture. The cells adhered to the material pore walls and pores, and protruded pseudopods into the pores. When cultured for 5 days, the cells secreted a large amount of extracellular matrix, and the cells were connected to each other through the matrix and gradually covered the surface of the material. The cell growth state, matrix secretion and cell coverage area of the RGD modified group were better than those of the porous tantalum group. (4) Western blot detection results showed that the expressions of type I collagen and integrin β1 protein in the RGD modified group were higher than those in the porous tantalum group and the blank group (P < 0.05). The expression levels of type I collagen, integrin β1, and focal adhesion kinase protein in the porous tantalum group were higher than those in the blank group (P < 0.05). (5) RT-PCR detection showed that the expressions of type I collagen, integrin β1, and focal adhesion kinase mRNA in the RGD modified group were higher than those of the porous tantalum group and the blank group (P < 0.05), and the expression of the porous tantalum group was higher than that of the blank group (P < 0.05). (6) The results showed that porous tantalum modified with RGD polypeptide can up-regulate the expression of type I collagen and integrin β1 on the cell membrane, activate the integrin/focal adhesion kinase signaling pathway, and promote cell adhesion and growth.

Recovery of the Hip Rotation Center with Tantalum in Revision Arthroplasty / Recuperação do centro de rotação do quadril com tântalo em artroplastias de revisão

Abstract Objective The objective of the present study is to evaluate the restoration capacity of the hip anatomic rotation center with the use of acetabular tantalum cups, associated or not with addition wedges. Methods Retrospective analysis of patients undergoing hip arthroplasty revision using tantalum between June 2013 and April 2017. The abduction angle of the acetabular component and the horizontal and vertical distances of the component to the center of anatomical rotation of the hipwere evaluated. The measurements were made through baseline radiographs performed in the preoperative period and at the last follow-up visit. Results A sample of 21 patients was obtained, 11 (52%) men and 10 (48%) women, with amean age of 62 ± 13 years old. The mean abduction angle of the acetabular cup decreased from 48.76° ± 13.88 ° in the preoperative period to 38.52° ± 10.08 ° in the postoperative period, and this difference was statistically significant (p = 0.001). The distances from the center of rotation of the prosthesis relative to the center of anatomical rotation of the hip were also lower after revision surgery with tantalum. The mean horizontal distance of 12.74 ± 10.59 mm was reduced to 7.11 ± 4.84 mm, and the mean vertical distance was reduced from 14.79 ± 10.05 mm to 4.89 ± 6.21 mm, and these reductions were statistically significant (p < 0.001). Conclusion Hip arthroplasty revision with tantalum cups, associated or not with addition wedges, significantly recovered the anatomical rotation center of the hip.

Resumo Objetivo O objetivo do presente estudo é avaliar a capacidade de restauração do centro de rotação anatômico do quadril com uso de copas acetabulares de tântalo associado ou não a cunhas de adição. Métodos Análise retrospectiva dos pacientes submetidos a revisão de artroplastia do quadril comuso de tântalo entre o período de junho de 2013 e abril de 2017. Foramavaliados o ângulo de abdução do componente acetabular e as distâncias horizontal e vertical do componenteao centro de rotação anatômicodoquadril.Asmedidas foramrealizadas através de radiografias da bacia realizadas no pré-operatório e na última visita de seguimento. Resultados Obteve-se uma amostra de 21 pacientes, 11 (52%) homens e 10 (48%) mulheres, com média de idade de 62 ± 13 anos. O ângulo médio de abdução da copa acetabular reduziu de 48,76° ± 13,88° no pré-operatório para 38,52° ± 10,08° no pósoperatório, sendo esta diferença estatisticamente significativa (p = 0,001). As distâncias do centro de rotação da prótese em relação ao centro de rotação anatômico do quadril também foram menores após a cirurgia de revisão com o tântalo. A distância média horizontal de 12,74 ± 10,59 mm foi reduzida para 7,11 ± 4,84 mm, e a distância média vertical foi reduzida de 14,79 ± 10,05 mm para 4,89 ± 6,21 mm, sendo essas reduções estatisticamente significativas (p < 0,001). Conclusão As revisões de artroplastia do quadril comcopas de tântalo, associadas ou não a cunhas de adição, recuperaram de forma significativa o centro de rotação anatômico do quadril.

A Novel High-Visibility Radiopaque Tantalum Marker for Biliary Self-Expandable Metal Stents

BACKGROUND/AIMS: Radiopaque metal markers are required to improve X-ray absorption by self-expandable metal stents (SEMSs) to enable precise stent placement. A new tantalum radiopaque marker was recently developed using an ultrasonic spray technique. The aim of the present study was to evaluate the safety and visibility of tantalum markers. METHODS: A total of three beagle dogs were used for a gastrointestinal tract absorption test. Five tantalum markers were placed in the stomach of each dog endoscopically. Excreted tantalum markers were collected, and their weights were compared to the original weights. In radiopacity tests, marker radiopacities on X-ray images were quantified using ImageJ software and compared with those of commercially available metal markers. Finally, the radiographic images of six patients who underwent biliary SEMS placement using tantalum marker Nitinol SEMSs (n=3) or gold marker Nitinol SEMSs (n=3) were compared with respect to marker brightness on fluoroscopic images. RESULTS: Absorption testing showed that the marker structures and weights were unaffected. Radiopacity tests showed that the mean brightness and total brightness scores were greater for tantalum markers (226.22 and 757, respectively) than for gold (A, 209 and 355, respectively; B, 204.96 and 394, respectively; C, 194.34 and 281, respectively) or platinum markers (D, 203.6 and 98, respectively). On fluoroscopic images, tantalum markers had higher brightness and total brightness scores (41.47 and 497.67, respectively) in human bile ducts than gold markers (28.37 and 227, respectively). CONCLUSIONS: Tantalum markers were found to be more visible than other commercially available markers in X-ray images and to be resistant to gastrointestinal absorption.

Clinical effects of the implantation of porous tantalum rod under three-dimensional C-arm positioning in treating ARCO I-II non-traumatic necrosis of the femoral head / 中华骨科杂志

Objective@#To evaluate the clinical effects of the implantation of porous tantalum rod under three-dimensional (3D) C-arm positioning in the treatment of ARCO I and II non-traumatic femoral head necrosis.@*Methods@#Fifty patients (58 hips, 39 males and 11 females, mean age 33.52 years) with non-traumatic femoral head in ARCO I-II were included from January 2009 to December 2011. All patients received implantation of porous tantalum rod. The 3D C-arm X-ray positioning was used in 24 patients (29 hips), while traditional C-arm X-ray positioning was performed in the other patients. The visual analogue scale (VAS), Harris score and superior rate were evaluated at 0.5, 1, 2, and 4 years after the surgery. Total hip arthroplasty was regarded as the end event for survival rate.@*Results@#In the 3D C-arm X-ray positioning group, the VAS score decreased from 7.17±1.00 points preoperatively to 2.38±0.86 points at half year, to 2.10±1.40 points at 1 year, to 2.38±1.66 points at 2 years, and to 2.21±1.47 points at 4 years postoperatively (F=98.78, P=0.00). Meanwhile, the Harris score increased significantly from 73.97±3.49 points preoperatively to 89.90±1.93, 89.93±3.26, 89.21±5.83, 88.57±5.70 points at the follow up, respectively (F=84.35, P=0.00). According to the analysis of the pre-operative and post-operative image data, there was no significant difference in progress in the ARCO staging at 23 hips duration the follow-up. Four hips were developed to ARCO III and two hips to ARCO II. Thus, the success rate of operation was 79% (23/29). There were two hips underwent total hip arthroplasty, so the survival rate of femoral head was 93% (27/29). The trend of VAS score and Harris score in the C-arm X-ray positioning group was in accordance with the 3D C-arm X-ray positioning group but without statistically significant difference (P>0.05). The operation duration 31.38±3.96 min, blood loss 36.72±5.59 ml, the ratio of distance of metal rod to bone cortex in femoral neck 0.48±0.10, and the distance of mental rod to center of necrosis 0.18±0.07 cm in 3D C-arm X-ray positioning group was superior to C-arm X-ray positioning group (respectively 41.97±4.64 min, 41.49±4.46 ml, 0.46±0.06, 0.23±0.10 cm, P<0.05).@*Conclusion@#The implantation of tantalum rod in treating ARCO I-II non-traumatic femoral head necrosis can increase the function of hip joint, relieve the symptoms of necrosis of femoral head, alleviate the progress of femoral head necrosis in X-ray, and obtain a higher survival rate. The 3D C-arm positioning in surgical operation could improve the accuracy and safety of surgery.

Research progress and clinical application of Tantalum in therepair of cartilage / 国际外科学杂志

Cartilage injury is very common in clinical,which can be caused by multiple factors,such as trauma,degenerative change and chronic strain.The clinical application of cartilage injury treatment includs conservative treatment,surgical treatment,and chondrocytes implant with cell scaffold,but all these methods are still unable to achieve a very satisfactory effect.Therefore,new explorations have been made in the field of cartilage repair,and the metal and other inorganic substances with better human compatibility have made great progress.Tantalum,a kind of transitional element,which has excellent chemical and physical properties and biocompatibility,is becoming more and more concerned in cartilage repair.This paper will review the research progress of tantalumin the repair of cartilage in recent years.

Study the mechanism of tantalum particles on the proliferation of osteoblasts / 实用医学杂志

Objective To investigate the effect of tantalum particles on the proliferation of osteoblasts and explore its mechanism. Methods Mouse osteoblasts MC3T3-E1 were co-cultured with micro-tantalum particles (micro-Ta)and Nano-tantalum particles(nano-Ta)of different concentrations respectively. CCK-8 assay was used to measure the cell viability at 6,12,24 and 48 h. According to the result of CCK-8 the group with the most prolif-erative effect was screened and the level of autophagy was detected by using Western blot,laser confocal microsco-py and transmission electron microscopy(SEM). Finally,to verify the role of autophagy in pro-proliferation effect of nano-Ta,the OD value was measured repeatedly in combination with autophagy inducer and inhibitor. Results 100 ng/mL micro-Ta treated groups had obvious proliferative effect but autophagy was not detected. 20 μg/mL nano-Ta treated groups had obvious proliferative effect and autophagy was detected. CCK-8 assay revealed that autophagy inhibitor can significantly inhibited cell proliferation of nano-Ta treated group. Conclusion Nano-Ta could pro-mote cell proliferation by inducing autophagy,and micro-Ta may promote osteoblast proliferation through other non-autophagy pathway.

The application of 3D printed customized porous tantalum acetabular patch for adult DDH hip reconstruction / 中华骨科杂志

Objective To explore the feasibility,safety and efficacy of customized porous tantalum acetabular patch made by three-dimensional (3D) printing technique in treating adult developmental dysplasia of the hip (DDH).Methods Eight adult patients with Crowe Ⅰ type DDH (2 men and 6 women,with a mean age of 43.75±7.81 years,range 33-58 years) who were treated with 3D printed customized porous tantalum acetabular patch hip reconstruction from January 2017 to September 2017 were included.The 3D printing technique was used for reconstructing and designing the optimal acetabular patch for the personalized hip joint of each patient.The acetabular patch was subjected to porous processing and finite element analysis until the biomechanical requirements were met.The 3D printing of porous tantalum acetabular patch and post-processing was subsequently performed.The acetabular patch was implanted through the anterior approach of the hip joint.The operative duration,intraoperative blood loss and complications were recorded.All the included patients were followed up at 1.5,3 and 6 months postoperatively.Pain was assessed using the visual analog scale (VAS),and the hip joint function was evaluated using the Harris score and gait analysis.The patients underwent anterior-posterior radiography and 3D computed tomography of the hip joint aiming to observe the position of the acetabular patch and osteoarthritis progression.Results The mean operative duration was 1.13±0.23 h,and the mean blood loss was 114.17±41.22 ml.All patients were followed up for 6 to 12 months,with an average of 8.2 months.The mean lateral central-edge angle and anterior central-edge angle ranged from 9.83°±5.34° preoperatively to 32.67°±2.53° postoperatively and from 3.83°± 2.79° preoperatively to 21.67°± 1.87° postoperatively,respectively.The rate of acetabular coverage increased from 57.33％±7.97％ preoperatively to 87.33％±4.56％ postoperatively.The VAS and Harris scores ranged from 2.92± 0.79 preoperatively to 0.83±0.72 postoperatively and from 69.67±4.62 preoperatively to 84.25±4.14 postoperatively with statistically significant difference,respectively.The results of gait analysis showed that the step speed,stride,the range of motion of hip and knee were better than that preoperatively.The images suggested a close contact between the tantalum acetabular patch and the iliac bone without loosening and progress of osteoarthritis in hip joint.Conclusion 3D printed customized porous tantalum acetabular patch could reconstruct the defect of acetabular,increase the coverage,and delay the progress of osteoarthritis of the hip joint.This method could reduce the difficulty of hip reconstruction,and the patients could obtain better joint function at the early stage.

In vivo study of 3D printed porous tantalum implant on osseointegration / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This work aims to investigate the effect of porous tantalum and porous titanium on osseointegration.</p><p><b>METHODS</b>Two kinds of porous materials with same microporous parameters, namely, porous tantalum and porous titanium, were fabricated by computer-aided design (CAD) modeling and 3D printing technology. A defect model was established in 24 New Zealand white rabbits in the bilateral femoral lateral malleolus at the left and right side of each animal. Then, animals were randomly divided into two groups, and bone defects were repaired by porous tantalum and porous titanium (experimental and control groups, respectively). Animals were sacrificed at two, four, and eight weeks after implantation. Gross observation and methylene blue-acid fuchsin staining were used to observe osseointegration of the implant and bone interface, and the osseointegration strength of implant bone interface was tested by push-out test.</p><p><b>RESULTS</b>At two, four, and eight weeks after operation, the new bone tissue in the two groups increased gradually, and new bone trabecula appeared and grew into the pores of the materials. No significant difference (P>0.05) in osteogenesis and the strength of implant bone tissue interface between the two groups was observed.</p><p><b>CONCLUSIONS</b>3D
printed porous tantalum implants, which exhibit comparable osseointegration capabilities to porous titanium implants, can form an early biological combination with bone tissue.</p>

Research progress of porous tantalum in bone tissue engineering / 中国修复重建外科杂志

Objective : To review the basical research progress of porous tantalum in bone tissue engineering. Methods: The related basical research in fabrication, cytobiology, and surface modification of porous tantalum was reviewed and analyzed. Results: The outstanding physiochemical properties of porous tantalum granted its excellent performance in biocompatibility and osteointegration, as well as promoting cartilage and tendon tissue restoration. However, the clinical utilization of porous tantalum is somehow greatly limited by the complex and rigid commercial fabrication methods and extraordinary high cost. Along with the publication of novel fabrication and surface modification technology, the application of porous tantalum will be more extensive, the promotion in bone tissue regeneration will be more prominent. Conclusion: Porous tantalum has advantage in bone defect restoration, and significant breakthrough technology is needed in fabrication methods and surface modification.

Tantalum trabecular metal cup with trabecular metal augments for Paprosky type Ⅱ and type Ⅲ acetabular defects in revision hip arthroplasty / 中华骨科杂志

Objective To investigatc thc short-term clinical and radiographic outcomes of tantalum trabecular metal (TM) components associated with TM augments for Paprosky type Ⅱ and type Ⅲ acetabular defects in revision hip arthroplasty.Methods From June 2014 to April 2016,seventeen patients with aseptic loosening underwent revision total hip arthroplasty for Paprosky type Ⅱ or type Ⅲ acetabular defects with TM revision acetabular cups and TM augments.The subjects consisted of 5 males and 12 females with mean age of 56.6 years (range 30-75).Acetabular bony defects were Paprosky type Ⅱ A in 4 hips,Ⅱ B in 3 hips,Ⅲ A in 8 and Ⅲ B in 2 hips.The whole hip revision was performed in 13 hips and acetabular reconstruction in 4 hips.Preand post-operative functional outcomes were accessed by the Harris Hip Score.The vertical and horizontal position of the rotation center from the intertear drop line were measured and analyzed.Complications were recorded during the follow-up.Radiographic examination was performed after operation immediately by X-ray.The recent X-ray was conducted to assess bone ingrowths at the cup-bone or augments-bone interface,radiolucent lines and implant migration.Results All of the patients were followed-up for an average of 23 months (range 11-33 months).There was no infection,dislocation or periprosthetic fracture complications at the last followed-up.The Harris Hip Score was improved from 45.8±3.4 pre-operatively to 79.2±7.5 post-operatively (t=-16.8,P=0.00).The mean vertical distance of the center of rotation was 32.1±4.3 mm preoperatively and 14.5±2.3 mm postoperatively (t=14.8,P=0.00).The mean horizontal distance of the center of rotation was 33.6±6.1 mm preoperatively and 27.8±3.2 mm postoperatively (t=3.5,P=0.00).More than 3 radiographic signs of osseointegration were observed in 11 hips.No progressive radiolucent lines or component migration was observed.All the TM components were well-fixed at last follow-up.Conclusion Using tantalum TM cups with TM augments in revision hip arthroplasty could be regarded as an effective management for Paprosky type Ⅱ and type Ⅲ acetabular defects.This technology can avoid using over-large cup,provide reliable primary stability,restore the center of rotation with almost normal hip biomechanics and improve the functional outcome.

Expression and significance of osteogenic genes on porous tantalum-bone interface during osteogenesis / 中国组织工程研究

BACKGROUND:Previous studies have shown that home-made porous tantalum has non-toxicity and good biocompatibility, and can promote osteogenesis. Herein, we explore the mechanisms of tantalum-bone interface osseointegration.OBJECTIVE:To observe the morphological characteristics and expressions of integrin β1 and fibronectin on the interface between porous tantalum and bone tissues after implantation into the right rabbit femur, and to evaluate the biological mechanisms of tantalum-bone interface osseointegration.METHODS: Animal models of bilateral femoral condyle defects were made in Japanese big ear rabbits. Porous tantalum rod and allogeneic bone were respectively implanted into the left (experimental group) and right (control group) femur of rabbits. The animal specimens at the bone defect region were taken and made into paraffin sections and hard tissue sections at postoperative 2, 4, 8 weeks for morphological observation of new bone at the junction between the tantalum rod and host bone under light microscope, for osteogenic observation of the tantalum-bone interface under scanning electron microscope, and for immunohistochemical detection of integrin β1 and fibronectin expression.RESULTS AND CONCLUSION:Porous tantalum was bonded closely with the host bone. The loose and thick fibrous capsule was observed in the early stage and became thinner in the late stage shown by hematoxylin-eosin staining. The new bone was visible on tantalum-bone interface. Hard tissue slicing observation showed that the new bone was seen on the porous tantalum-bone interface, blood capillaries grew into the pores at postoperative 2 weeks and the pores were full of new bone tissues at postoperative 4 and 8 weeks. Under the scanning electron microscope, the osteoblasts appeared on the tantalum surface and in the pores at the early stage, and bone maturation and lamelar bone were seen at the late stage. The immunohistochemical results showed that the expression of integrin β1 in the experimental group was significantly lower than that in the control group at postoperative 2 weeks (P 0.05). In addition, there was a decline trend in the expression of integrin β1 and fibronectin atpostoperative 2, 4, 8 weeks. To conclude, the porous tantalum material is beneficial to enhance adhesion of osteoblasts on the surface and inside the micro-pores. Increased expression of integrin β1 and fibronectin on the tantalum-bone interface at early stage may promote early osteogenesis, while their decreased expression at bone maturing stage can promote osseointegration and bone remodeling.