Midterm Radiographic Results and Reoperations of Tantalum Trabecular Metal Cones in Knee Arthroplasties / Reoperações e resultados radiográficos de médio prazo do uso de cone de metal trabecular de tântalo nas artroplastias do joelho

Abstract Objective The management of bone loss represents a challenge in revisions of total knee arthroplasty (rTKA) and in complex primary total knee arthroplasties (TKAs). The purpose of the present study was to evaluate the midterm outcomes (5-year minimum follow-up) of knee reconstructions with tantalum trabecular metal (TM) cones on bone defects Anderson Orthopaedics Research Institute (AORI) 2 and 3. Materials and MethodsA retrospective analysis of the medical records of patients operated on between July 2008 and November 2014 was performed, collecting the following data: age, gender, laterality, body mass index, etiology of arthrosis, comorbidities, AORI classification of bone defects, causes for revision, readmissions, reoperations, perioperative and postoperative complications, radiographic signs of osteointegration, and maintenance of the TM support. Results A total of 11 patients with a mean follow-up of 7.28 years (standard deviation [SD] = 1.88; range = 5.12-10 years) was evaluated, with 1 patient operated upon for a primary arthroplasty, 6 for revision arthroplasties, and 4 for a second revision arthroplasty (re-revision). There were complications with the surgical wound, injury to the extensor mechanism and loosening of the femoral component in three of the patients that led to the necessity of four procedures due to complications with the surgical wound, injury to the extensor mechanism and loosening of the femoral component. Radiological signs of osteointegration of the trabecular cones were observed in all patients. We did not observe migration of the TM cones or the prosthetic components in the sample. Conclusion The tantalum metaphyseal cones were able to provide efficient structural support to prosthetic implants with radiographic signs of osteointegration in the medium term.

Resumo Objetivo O manejo da perda óssea representa um grande desafio em cirurgias de revisão de artroplastia do joelho (rATJ) e em artroplastias totais do joelho (ATJ) primárias complexas. O objetivo do presente estudo foi avaliar os resultados em médio prazo (seguimento mínimo de 5 anos) das reconstruções de joelho nas quais cones de metal trabecular (MT) de tântalo foram utilizados para tratamento de defeitos ósseos tipos 2 e 3, de acordo com a classificação proposta pela Anderson Orthopaedic Research Institute (AORI). Métodos Feita análise retrospectiva dos prontuários dos pacientes operados entre julho de 2008 e novembro de 2014, coletando-se os seguintes dados: idade, gênero, lateralidade, índice de massa corporal, etiologia da artrose, comorbidade, classificação AORI da falha óssea, causa da revisão da artroplastia total do joelho, reinternações, reoperações, complicações peri- e pós-operatórias, ocorrência de osteointegração radiográfica e manutenção da função de suporte do MT. Resultados Foram avaliados 11 pacientes com tempo médio de seguimento de 7,28 anos (desvio padrão [DP] = 1,88; variação = 5,12-10 anos), sendo que 1 paciente foi submetido a artroplastia primária, 6 a artroplastia de revisão e 4 a segunda revisão de artroplastia (re-revisão). Três pacientes necessitaram de quatro reoperações devido a complicações com a ferida operatória, a lesão do mecanismo extensor e a soltura do componente femoral. Sinais de osteointegração dos cones trabeculados foram observados em todos os pacientes. Não observamos migração do cone de MT ou dos componentes protéticos. Conclusão Os cones metafisários de tântalo foram capazes de prover suporte estrutural eficiente aos implantes protéticos com sinais radiográficos de osteointegração em médio prazo.

Application of porous tantalum Jumbo cup in revision of hip arthroplasty / 中国骨伤

OBJECTIVE@#To investigate the clinical effect of porous tantalum Jumbo cup on acetabular reconstruction in revision of total hip arthroplasty.@*METHODS@#From September 2014 to December 2017, 18 patients(18 hips) with acetabular defect were reconstructed by porous tantalum Jumbo cup technology, including 6 males and 12 females;the age ranged from 54 to 76 years old with an average of(63.8±15.3) years. There were 6 cases of paprosky typeⅡA, 8 cases of typeⅡB, 2 cases of typeⅡC and 2 cases of type Ⅲ a. Harris score and visual analogue scale (VAS) were performed before and after operation. Imaging examination was performed to evaluate the position of hip rotation center and prosthesis, and to judge whether acetabular loosening, displacement and complications existed.@*RESULTS@#All cases were followed up for 13 to 49 months, with an average of 20.6 months. Harris score increased from 54.6±4.7 to 86.5±3.2 one year after operation(P<0.01), and VAS score decreased from 6.8±0.7 to 0.8±0.6 one year after operation (P<0.01). The transverse coordinate of hip rotation center was (3.52±0.72) cm before operation and (3.47±0.54) cm after operation (P>0.05). The longitudinal coordinate of hip rotation center was improved from (3.02±0.84) cm before operation to (2.35±0.53) cm after operation (P<0.01). During the follow-up period, the Jumbo cup was well fixed without loosening and displacement, the acetabular cup had bone ingrowth in varying degrees, and no light transmission line and osteolysis around the acetabular cup were found. No complications such as infection and nerve injury occurred.@*CONCLUSION@#The method of reconstructing acetabular bone defect with porous tantalum Jumbo cup is simple and easy, the early stability of acetabulum is good, and the short-term follow-up effect is good.

Uso de conos de metal trabecular para defectos óseos severos en cirugía de revisión de reemplazo total de rodilla / The use of trabecular metal cones for the management of severe bone defects in revision total knee replacement

Introducción: Las alternativas reconstructivas para defectos óseos severos en la cirugía de revisión de prótesis son las camisas metafisarias, los conos de metal trabecular y el injerto óseo impactado o estructural. El objetivo del estudio fue analizar la tasa de osteointegración de los conos de metal trabecular en pacientes con cirugía de revisión de prótesis total de rodilla. El objetivo secundario fue analizar los resultados funcionales, las tasas de complicaciones y reoperaciones. Materiales y Métodos: Cohorte retrospectiva de pacientes con conos de metal trabecular colocados en la cirugía de revisión de prótesis y un seguimiento mínimo de 2 años. Se evaluaron las causas de la revisión, cirugías previas, tipo de defecto óseo, cantidad y tipo de conos utilizados, y los diseños de las prótesis. Se realizó una evaluación clínico-radiográfica, se registraron las complicaciones y las revisiones ulteriores. Resultados: Se evaluó a 35 pacientes (49 conos de metal trabecular) en forma retrospectiva, con un seguimiento promedio de 32.1 meses. La mayoría de los defectos eran tibiales AORI 3, seguidos de los femorales tipo 3. La tasa de osteointegración de los conos fue del 94%; la de complicaciones, del 20% y la de reoperaciones, del 8,5%. El KSS objetivo promedio aumentó de 39 en el preoperatorio a 71 en el último control y el puntaje de la EAV promedio fue 8 y 2,5, respectivamente. Conclusión: La excelente tasa de osteointegración (94%) y los buenos resultados clínicos posicionan a los conos de metal trabecular como una alternativa para los defectos óseos severos. Nivel de Evidencia: IV

Introduction: Major bone defects represent a challenge during revision total knee arthroplasty (TKA) and there is still considerable debate about the best therapeutic option. The purpose of this study was to retrospectively assess the osseointegration rate of trabecular metal cones in revision TKA with severe bone defects. The secondary purpose was to evaluate the functional outcomes and complication and reoperation rates. Materials and Methods: A single-center, retrospective cohort including all consecutive cases of revision TKA using trabecular metal cones. All patients with a minimum 2-year follow-up were included in the study. Reasons for revision, number of previous surgeries, type of bone defect, and number and type of trabecular cones used were evaluated. Clinical and radiological outcomes were also analyzed as well as complications rates. Results: 35 patients (49 cones) were evaluated with a mean follow-up of 32.1 months (24-62). Most defects were localized in the tibia and were classified as AORI type 3. The rate of osseointegration of the cones was 94%; the complication rate, 20%; and the reoperation rate, 8.5%. The mean KSS increased from 39 preoperatively to 71 at the last follow-up, and the mean VAS from 8 to 2.5. Conclusion: The excellent osseointegration rate (94%), added to the good clinical outcomes, position the trabecular metal cones as an alternative to treat severe bone defects. Level of Evidence: IV

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.

Application of a novel porous tantalum implant in rabbit anterior lumbar spine fusion model: in vitro and in vivo experiments / 中华医学杂志(英文版)

BACKGROUND@#Some porous materials have been developed to enhance biologic fusion of the implants to bone in spine fusion surgeries. However, there are several inherent limitations. In this study, a novel biomedical porous tantalum was applied to in vitro and in vivo experiments to test its biocompatibility and osteocompatibility.@*METHODS@#Bone marrow-derived mesenchymal stem cells (BMSCs) were cultured on porous tantalum implant. Scanning electron microscope (SEM) and Cell Counting Kit-8 assay were used to evaluate the cell toxicity and biocompatibility. Twenty-four rabbits were performed discectomy only (control group), discectomy with autologous bone implanted (autograft group), and discectomy with porous tantalum implanted (tantalum group) at 3 levels: L3-L4, L4-L5, and L5-L6 in random order. All the 24 rabbits were randomly sacrificed at the different post-operative times (2, 4, 6, and 12 months; n = 6 at each time point). Histologic examination and micro-computed tomography scans were done to evaluate the fusion process. Comparison of fusion index scores between groups was analyzed using one-way analysis of variance. Other comparisons of numerical variables between groups were made by Student t test.@*RESULTS@#All rabbits survived and recovered without any symptoms of nerve injury. Radiographic fusion index scores at 12 months post-operatively between autograft and tantalum groups showed no significant difference (2.89 ± 0.32 vs. 2.83 ± 0.38, F = 244.60, P = 0.709). Cell Counting Kit-8 assay showed no significant difference of absorbance values between the leaching liquor group and control group (1.25 ± 0.06 vs. 1.23 ± 0.04, t = -0.644, P = 0.545), which indicated the BMSC proliferation without toxicity. SEM images showed that these cells had irregular shapes with long spindles adhered to the surface of tantalum implant. No implant degradation, wear debris, or osteolysis was observed. Histologic results showed solid fusion in the porous tantalum and autologous bone implanted intervertebral spaces.@*CONCLUSION@#This novel porous tantalum implant showed a good biocompatibility and osteocompatibility, which could be a valid biomaterial for interbody fusion cages.

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.

Uso de copas de tantalio trabecular para la reconstrucción acetabular compleja: Resultados de una serie de 42 casos y un seguimiento promedio de tres años / Trabecular metal cup outcomes in complex acetabular reconstruction. Review of 42 cases with a 3-year follow-up

Introducción: El objetivo de este estudio es analizar nuestros resultados clinico-radiologicos con el uso de copas de tantalio trabecular para la reconstruccion de acetabulos complejos, tanto en cirugias primarias como en revisiones, y compararlos con series similares de otros autores. Materiales y Métodos: Se llevo a cabo una revision retrospectiva de una serie de 42 cirugias (29 revisiones y 13 artroplastias primarias) en 40 pacientes, entre marzo de 2010 y marzo de 2016. La serie incluyo a 20 mujeres y 20 hombres, con una edad promedio de 60 anos (rango 27-93). El seguimiento promedio fue de 37 meses (rango 12-84). Todos los pacientes fueron tratados con el mismo tipo de metal trabecular. Resultados: Al promedio de seguimiento mencionado la supervivencia del componente acetabular fue del 97,6%. Un paciente fue tratado con artroplastia de reseccion debido a una infeccion persistente. La tasa de complicaciones totales fue del 12% y el promedio del Harris Hip Score posoperatorio fue de 81,54 (rango 63,25-92,75). Conclusiones: Aunque se necesita un seguimiento mas prolongado, el uso de copas de metal trabecular logra resultados prometedores para el tratamiento de acetabulos complejos. Nivel de Evidencia: IV

Introduction: The purpose of this paper is to review of our clinical and radiological results with the use of trabecular metal cups for complex acetabular reconstruction, both in primary and revision total hip arthroplasties, and to compare our results with those in similar series from other authors. Methods: A series of 42 surgeries (29 hip revisions and 13 primary total hip arthroplasties) in 40 patients, between March 2010 and March 2016 was retrospectively reviewed. The series included 20 women and 20 men, with a mean age of 60 years (range 27-93). The mean follow-up was 37 months (range 12-84). All patients were treated with the same type of trabecular metal. Results: At the average follow-up, the survival of the acetabular component was 97.6%. One patient required resection arthroplasty due to persistent infection. Overall complication rate was 12% and the average postoperative Harris Hip Score was 81.54 (range 63.25-92.75). Conclusions: Despite further follow-up is needed, trabecular metal cup use for complex acetabular reconstruction shows promising results. Level of Evidence: IV

Effects of RGD peptides-grafted porous tantalum on morphological change of MG63 osteoblasts-tantalum conjunctive interface and expression of osteogenesis factors / 北京大学学报(医学版)

OBJECTIVE@#To investigate the effects of the Arg-Gly-Asp polypeptedes (RGD) peptides-modified porous tantalum surface on osteoblasts morphology and expressions of osteogenesis factors, and to evaluate RGD peptides promotes junctura ossium of tantalum-bone interface in vivo.@*METHODS@#RGD peptides of different concentrations (1 g/L, 5 g/L, and 10 g/L) were loaded to porous tantalum slices with a diameter of 10 mm and a thickness of 3 mm by physical absorption. The 3rd generation of MG63 cells were co-cultured with tantalum and divided into 4 groups: Ta-cells (control) group, 1 g/L cells/Ta/RGD group, 5 g/L cells/Ta/RGD group, and 10 g/L cells/Ta/RGD group. Porous tantalum compo-sites and osteoblasts-tantalum interface were observed by scanning electron microscopy. The adhesion rate of osteoblasts was detected and immunocytochemistry was used to detect the expressions of filamentous actin (F-actin), osteocalcin (OC) and fibronectin (FN).@*RESULTS@#The scanning electron microscope (SEM) revealed that osteoblasts distributed on the surface of porous tantalum and secreted extracellular matrix on outside and inner of micro-pores. The osteoblasts adhesion rate on porous tantalum modified with RGD was higher than that in the unmodified porous tantalum at the end of 24, 48, and 72 hours. The best adhesion effect was got in 5 g/L cells/Ta/RGD group at hour 48 [(68.07±3.80) vs. (23.40±4.39), P<0.05]. The results of immunocytochemistry showed that the expressions intensity of F-actin, OC and FN in osteoblasts on porous tantalum modified groups with RGD were stronger than that in the unmodified groups, and the expressions of 5 g/L cells/Ta/RGD group were significantly higher than those in the 10 g/L group and 1 g/L group [OC: (18.08±0.08) vs. (15.14±0.19), P<0.05; (18.08±0.08) vs. (14.04±0.61), P<0.05. FN: (24.60±0.98) vs. (15.90±0.53), P<0.05; (24.60±0.98) vs. (15.30±0.42), P<0.05. F-actin: (29.20±1.31) vs. (24.50±1.51), P<0.05; (29.20±1.31) vs. (16.92±0.40), P<0.05]. Correspondingly F-actin in osteoblasts was showed in longitudinal arrangement, and the expressions intensity was stronger than those OC and FN.@*CONCLUSION@#The RGD peptides is beneficial to enhance adhesion of osteoblast, spreading and reorganization of cytoskeleton on porous tantalum surface and improve the interface morphology, further promoting osteoblasts-tantalum conjunctive interface osseointegration.

In Vitro Quantification of the Radiopacity of Onyx during Embolization / 신경중재치료의학

PURPOSE: Onyx has been successfully applied in the treatment of various neurovascular lesions. However, some experience is required to get accustomed to its unpredictable fluoroscopic visibility during injection. This in vitro study aimed to evaluate the characteristics of radiopacity change in a simulated embolization procedure. MATERIALS AND METHODS: Using a bench-top Onyx injection experiment simulating a typical brain arteriovenous malformation embolization, nine cycles of casting modes (continuous injection) and plugging modes (injection with intermittent pauses) were performed. Radiodensity of Onyx droplets collected from the microcatheter tip and the distal head portion of the microcatheter were measured as time lapsed. Distribution of droplet radiodensity (radiodensity) and distribution of radiographic grade (grade) were analyzed and compared by repeated measurements. RESULTS: Within-group analysis revealed no significant radiodensity change with time (P>0.05). The radiodensity was significantly higher in the casting mode than in the plugging mode (P<0.01). The lateral radiograph of the microcatheter showed higher radiopacity (P<0.01) and better evenness (P<0.01) in the casting mode than in the plugging mode. A significant difference in microcatheter attenuation (both radiographic grade mean and SD; P<0.01) was noted between the two modes. Radiodensity had a significant influence on the radiopacity and radiopacity evenness of the microcatheter. CONCLUSION: The radiopacity of the Onyx can vary significantly over time because of early precipitation of tantalum powder. Radiopacity decreased significantly during plugging modes, characterized by pauses between injections.

Acetabular revision in total hip arthroplasty with tantalum augmentation and lyophilized bovine xenograft / Revisão acetabular em artroplastia total de quadril com cunhas de tântalo associadas a enxerto ósseo bovino liofilizado

Abstract Objective To evaluate a mixed technique of acetabular reconstruction, which uses trabecular metal in the form of tantalum augments associated with lyophilized bovine xenograft. Methods Fifteen patients were evaluated prospectively, who underwent acetabular reconstruction with impacted lyophilized bovine xenograft associated with the use of tantalum augments. The main outcome was the failure of the tantalum-bone interface. Results The population had a mean age of 58.33 years ± 14.27; the majority was female, 80%. Of the total subjects, 66.7% were operated for failure in primary arthroplasty. The mean follow-up time was 45.2 months ± 11.39. The failure rate of the method in the period and population studied was 6.7%. Conclusion An extremely high index (93.3%) of success was observed in an average time of 45.2 months of follow-up. Data were comparable to current literature, demonstrating that the technique employed and proposed is adequate for hip reconstruction in young patients.

Resumo Objetivo Avaliar uma técnica mista de reconstrução acetabular que usa metal trabecular na forma de cunhas de tântalo associadas com enxerto ósseo bovino liofilizado. Métodos Foram avaliados prospectivamente 15 pacientes submetidos à reconstrução acetabular com enxerto bovino liofilizado impactado associado ao uso de cunhas de tântalo. O principal desfecho avaliado foi a falha da interface tântalo-osso. Resultados A população apresentou idade média de 58,33 anos ± 14,27, a maioria do sexo feminino 80%. Do total, 66,7% foram operados por falha da artroplastia primária. O tempo médio de seguimento foi de 45,2 meses ± 11,39 meses. A taxa de falha do método no período e na população estudada foi de 6,7%. Conclusão Observou-se um índice extremamente elevado (93,3%) de sucesso em um tempo médio de 45,2 meses de seguimento. Os dados são comparáveis à literatura corrente, o que demonstra que a técnica empregada e proposta é adequada para reconstrução de quadril em pacientes jovens.

Revision Total Hip Arthroplasty Using Tantalum Augment in Patients with Paprosky III or IV Acetabular Bone Defects: A Minimum 2-year Follow Up Study / 대한고관절학회지

PURPOSE: The purpose of this study is to report the short-term outcomes of revision total hip arthroplasty (THA) using tantalum augments in patients with severe acetabular bone defects. MATERIALS AND METHODS: We retrospectively analyzed 15 revision THAs performed in 15 patients using tantalum augments between June 2010 and December 2013. Acetabular bone defects were Paprosky type IIIA in 7 hips, type IIIB in 7, and type IV in 1. The causes of revision surgery were aseptic loosening in 12 hips and deep infection in 3. Revisions were first in 1 hip, second in 3, and third in 11. Six patients were male and 9 female with a mean age of 59 years (range, 48-75 years). Mean follow-up was 29 months (range, 24-48 months). RESULTS: Mean Harris hip score was improved from 34 points (range, 12-54 points) preoperatively to 84 points (range, 38-90 points) at final follow-up. On the final follow-up radiographs, there were 12 hips (80.0%) with stable fixation of the acetabular cup, 2 (13.3%) with secondary stability after mild acetabular protrusion, and 1 (6.7%) with radiolucency around the acetabular cup without mechanical symptoms. Complications included one patient with acute hematogenous infection managed by surgical debridement and long-term antibiotic therapy. There were no cases with nerve palsy or dislocation during the follow-up period. CONCLUSION: The present study showed satisfactory clinical and radiographic outcomes of revision THA using tantalum augments due to severe acetabular bone defects of Paprosky type III or IV at a minimum follow-up of 2 years.

Treatment of Steroid-induced Osteonecrosis of Femoral Head by Porous Tantalum Rod and Gugutou Huaisiyu Capsule / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the curative effect of porous tantalum rod and Gugutou Huaisiyu Capsule (GHC) for steroid-induced osteonecrosis of femoral head (SONFH).</p><p><b>METHODS</b>A total 60 hips of 50 SONFH patients were randomly assigned to the treatment group and the control group according to grouping time, 25 in each group (30 hips). Patients in the control group were implanted with porous tantalum rod, while those in the treatment group additionally took GHC (5 pills each time, three time per day for 2 successive months; and then twice per day for 4 successive months). Then all patients were followed-up to observe Harris hip score. The curative effect and the femoral head survival time were assessed.</p><p><b>RESULTS</b>A total of 49 patients (59 hips) were followed-up. The Harris hip score of the two groups at the final follow-up was significantly improved after treatment, with statistical difference when compared with before treatment (P < 0.01). Besides, it was higher in the treatment group than in the control group. The curative effect and the survival time were superior in the treatment group, with statistical difference when compared with the control group (P < 0.05).</p><p><b>CONCLUSIONS</b>Porous tantalum rod combined GHC got better effect in treating SONFH. It could significantly improve the function of affected hips and prolong the survival time of femoral head.</p>

Results of Total Hip Arthroplasty after Core Decompression with Tantalum Rod for Osteonecrosis of the Femoral Head

BACKGROUND: Early stage osteonecrosis of the femoral head (ONFH) has many treatment options including core decompression with implantation of a tantalum rod. The purpose of this study was to evaluate clinical and radiological outcomes and potential complications during conversion total hip arthroplasty (THA) in such patients. METHODS: Six male patients (8 hips) underwent THA subsequent to removing a tantalum rod (group I) from April 2010 to November 2011. We retrospectively reviewed the medical records of these patients. We enrolled 12 age- and sex-matched patients (16 hips) during the same period, who had undergone primary THA without a previous operation as the control group (group II). All patients were followed for at least 3 years. We checked the Harris hip score (HHS), operative time, and volume of blood loss. Radiological results, including inclination, anteversion of the acetabular cup, presence of periprosthetic osteolysis, and subsidence of femoral stem were checked at the last follow-up. RESULTS: The mean preoperative HHS values were 56.5 (range, 50 to 62) and 59.1 (range, 42 to 70) in groups I and II, respectively. The HHS improved to 96.0 (range, 93 to 100) and 97.6 (range, 93 to 100), respectively, at the 3-year follow-up (p = 0.172). Mean operation time was 98.8 minutes (range, 70 to 120 minutes) in group I and 77.5 minutes (range, 60 to 115 minutes) in group II (p = 0.006). Total blood loss volumes were 1,193.8 mL (range, 960 to 1,360 mL) and 944.1 mL (range, 640 to 1,280 mL) in groups I and II, respectively (p = 0.004). No significant differences in inclination or anteversion of acetabular cup and no evidence of osteolysis or subsidence of the femoral stem were reported in either group in radiological follow-up results. However, one case of squeaking occurred in group I during the follow-up. CONCLUSIONS: The two groups showed no clinical or radiological differences except extended operative time and increased blood loss. However, the incidence of squeaking (1 of 8 hips) was higher, as compared to the control group or previously reported values.

Short-term effects on reconstruction of Paprosky type III severe acetabulum bone defect with tantalum metal block / 中国骨伤

<p><b>OBJECTIVE</b>To investigate methods and short-term effects on tantalum metal block for reconstruction of Paprosky type III severe acetabulum bone defect.</p><p><b>METHODS</b>Twelve patients (12 hips) with Paprosky type III severe acetabulum bone defect,treated with tantalum metal block in revision of total hip arthroplasty, were retrospectively analyzed from March 2009 to December 2012. Among the patients, there were 5 males and 7 females aged from 45 to 78 years old with an average of 64 years old; the courses of disease ranged from 3 to 32 months with an average of 16 months. According to classification of Paprosky, all patients were Paprosky type III acetabulum bone defect. All patients were used tantalum metal block in revision of total hip arthroplasty, and large diameter biological acetabulum cups were used in combination. Operative time,blood loss and postoperative complications were recorded and compared, Harris score were used to evaluate clinical effects.</p><p><b>RESULTS</b>Eleven patients ( 11 hips) were followed up from 9 to 36 months with an average of 25 months, 1 case was lost to follow-up for dying in car accident. The incisions were healed at stage I . Operative time ranged from 2 to 6 h with an average of 3 h; blood loss was 300 to 1 600 ml with an average of 900 ml. No deep venous thrombosis, periprosthetic femoral fracture and infection, sciatic nerve injury occurred after operation. Harris score were improved from (46.25 ± 8.99) before operation to (83.75 ± 6.76) after operation. There was significant difference in Harris score before and after operation (t = 3.14, P = 0.00 < 0.05), and 7 cases got excellent results, 2 good and 2 moderate. CONCLUCSION: Tantalum metal block is suitable for revision of Paprosky III acetabulum bone defect, could repair different kinds of acetabulum cup defect, could fill up inclusive defect of inner wall combined with particulate bone graft, induce bone growth pressured between metal block and metal cup, provide a new further choose for the treatment of Paprosky type III severe acetabulum bone defect.</p>

Structural characteristics and biocompatibility of a new nano-Ta-Ti alloy rod fabricated by laser melting technique / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the structural characteristics and biocompatibility of a novel nano-Ta-Ti alloy rod for its potential application in internal fixation.</p><p><b>METHODS</b>Ta coating of a Ti alloy rod with nano-Ta (tantalum) powder was performed using laser melting with symmetrical grooves repleted with nano-Ta powder along the whole length. The microstructure of the cross section of Ta-Ti alloy rod, pore diameter and components of the coating were analyzed using scanning electron microscopy. The influence of this nano-Ta-Ti alloy on proliferation and differentiation of MC3T3-E1 cells was evaluated by MTT cytotoxicity test and ALP activity test.</p><p><b>RESULTS</b>Under scanning electron microscope, the Ta-coating surface presented with a gross porous (200-300 µm) structure with dense fusion between Ta particles, and no new element was produced after laser melting. Biocompatibility evaluation showed that Ti alloys with and without Ta coating both promoted the proliferation of MC3T3-E1 cells, but the coated alloy showed better performance and obviously promoted the differentiation of the osteoblasts.</p><p><b>CONCLUSION</b>Alloying between Ta and Ti can be accomplished successfully by laser melting technique, and the alloy obtained has ideal surface structure and good biocompatibility.</p>

Progress on tantalum rod implanting for the treatment of femur head necrosis / 中国骨伤

Incorrect treatment for femur head necrosis can cause collapse of femoral head and tresult in severe harm for the patients (especially for the patient with middle-aged and young). The structure and mechanics characteristics of tantalum rod is similar to bone tissue, it higher strength and can adapt the internal environment of organism, so it has a large potency in treating femur head necrosis. Treatment of early femur head necrosis with tantalum rod implanting had alreadly widey applied at home and abroad, the method has the advantages of simple operation, little risk, less complication and beseems the patient with stage I - II of ARCO. But reasons that the difficult diagnosis of early femur head necrosis, localized effect of tantalum rod, different experience of medical worker,caused the contentions about effect of tantalum rod implanting. With development of science, tantalum rod implanting combined with correlative biotechnology should raise the effect in treating femur head necrosis.

Short-term curative effects of Tantalum rod treatment in early avascular necrosis / 中国骨伤

<p><b>OBJECTIVE</b>To explore the recent clinical curative effect of Tantalum rod in treating the early avascular necrosis.</p><p><b>METHODS</b>From January 2008 to November 2008, the 25 patients (39 hips) with early avascular necrosis accepted tantalum rod placement and included 9 males (11 hips) and 16 females (28 hips) with an average age of 37 years old ranging from 18 to 74 years old. Four patients (6 hips) caused by Alcoholic, 6 patients (8 hips) by hormone, 2 cases (2 hips) by traumatic, 13 cases (23 hips) by idiopathic. Steinberg preoperative stage involved 7 hips in period I, 24 hips in period II, 8 hips in period III. Curative effect analysis included preoperative and postoperative Harris score, radiographic changes and hip replacement for follow-up to accept the end of the femoral head survival rate.</p><p><b>RESULTS</b>All patients were followed up for 6 to 47 months (averaged 37.4 months). All 12 hips imaging appeard progress,including tantalum rod exit in 1 hip, hip hemiarthroplasty collapse in 3 hips, the area increased to avascular necrosis in 8 hips. Six hips accepted total hip replacement, including imaging progress in 5 hips (41.7%, 5/12), no imaging progress in 1 hip (3.7%,1/27). All hips' Kaplan-Meier survival curves showed 6-month survival rate was (97.4 +/- 2.5)% after tantalum stick insertion, 1-year survival rate was (94.7 +/- 3.6), and 2-year survival rate was (88.6 +/- 5.4)%, 3-year survival rate was (72.5 +/- 11.2).</p><p><b>CONCLUSION</b>It is effective for treatment of avascular necrosis of femoral head in Steinberg I and II by Tantalum rod, and it can effectively relieve femoral head replacement time.</p>

Cytotoxicity of a new biomedical titanium alloy Ti-25Nb-10Ta-1Zr-0.2Fe / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the cytotoxicity of a new type of titanium alloy Ti-25Nb-10Ta-1Zr-0.2Fe by studying the induced proliferation of L929 cells in contrast with other titania widely used in clinical practice.@*METHODS@#The cell line was treated with extracting liquid containing different concentrations of titanium alloys. The number and morphology of cells was observed under an inverted phase contrast microscope. MTT was used to measure the relative growth rate (RGR) and judge the cytotoxicity grade. Flow cytometry was used to observe cell cycle progression.@*RESULTS@#The RGR of TNTZ group cells at the 3 time points was (93.7±0.8), (100.6±0.4), and (106.4±0.3); the cytotoxicity grade was 1, 0 and 0 after treating for 1, 3 and 5 days; with influence on neither the cell morphology nor the cell cycle. The flow cytometry showed that the sequence of S phase cells was Ti>TNTZ>TC4>blank control >TC4ELI, with no significant difference (P>0.05). None of the 4 materials inhibited the cell proliferation.@*CONCLUSION@#The cell morphology and proliferation are not affected by TNTZ. The new titaniu alloys shows good cyto-compatibility. The cytotoxicity is grade 0, meeting the clinical application standard.

Cirugía de revisión acetabular utilizando un cotilo modular con superficie de metal trabecular de tantalio: resultados a corto plazo / Acetabular revision surgery using a modular acetabular cup coated with trabecular metal of tantalum: short term results

Objectives: To evaluate short-term clinical results of patients performed acetabular revision surgery using a Trabecular Tantalum coated modular acetabular cups. Materials and Methods: This is a retrospective and descriptive analysis of a serie of 32 consecutive patients (34 hips) with acetabular revision surgery (23 women, 9 men, mean age 70.7 years), mean follow-up 32 month (12-60). The Paprosky and the AAOS acetabular defects classifications were assessed. According to Paprosky acetabular defects classification, there were eleven type I, two IIA, three IIB, nine IIC, seven IIIA and two IIIB. According to AAOS acetabular defects classification there were thirteen patients with type 1, nine patients with type 2, ten type 3 and two type 4. The percentage of own acetabular bone in contact with the new cup was recorded for each patient at the time of surgery and was 45 percent (range from 20 to 80 percent), with 23 patients presenting less than 50 percent of bone contact (mean 35 percent). Postoperatively, osseous integration was radiographically assessed. Functional results were evaluated according to the Harris Hip Score (HSS). The complications related to the implant were also recorded. Results: In all radiographic assessments performed at 3, 6 and 12 month postoperatively an integrated cup without signs of migration or osteolysis was observed. Four patients (11.8 percent) presented recurrent hip dislocation that required a revision surgery without further cup revision. The final clinical assessment was performed at a mean of 26 month after surgery (12-60) with a mean HHS of 91.8 points. Conclusion: Trabecular tantalum coated modular acetabular cups in acetabular revision surgery shows good short term clinical results even with acetabular defects greater than 50 percent. No cup loosening was observed in these series.

Objetivo: Evaluar los resultados clínicos a corto plazo de pacientes sometidos a cirugía de revisión acetabular utilizando cotilos modulares con superficie de metal trabecular de tantalio. Material y Métodos: Estudio retrospectivo-descriptivo de una serie consecutiva de 32 pacientes (34 caderas) sometidos a cirugía de revisión acetabular (23 mujeres, 9 hombres, edad promedio 70,7 años), seguimiento promedio 32 meses (12-60). Se clasifican los defectos acetabulares de acuerdo ala clasificación de Paprosky y de la AAOS. Según la clasificación de Paprosky de los defectos acetabulares, 11 pacientes tenían categoría I, 2 categoría IIA, 3 categoría IIB, 9 categoría IIC, 7 categoría IIIA y 2 categoría IIIB. Según la clasificación de la AAOS, 13 pacientes correspondieron a nivel 1, 9 pacientes a nivel 2, 10 a nivel 3 y 2 a nivel 4. Se registra el porcentaje de hueso propio acetabular en contacto con el nuevo cotilo de cada paciente que fue en promedio 45 por ciento (20-80 por ciento), presentándose en 23 caderas un porcentaje < 50 por ciento, el cual fue en promedio 35 por ciento. En el postoperatorio se evalúa la integración ósea mediante radiografías de pelvis. Se evalúan los resultados funcionales mediante el HHS (Harris Hip Score) y las complicaciones postoperatorias relacionadas con el implante. Resultados: En todas las radiografías postoperatorias realizadas a los 3, 6 y 12 meses se evidenciaba el cotilo integrado, sin signos de migración ni osteolisis. Cuatro pacientes (11,8 por ciento) presentaron luxaciones recidivantes de cadera, las cuales requirieron de una cirugía de revisión sin recambio del cotilo. La última evaluación clínica fue en promedio 26 meses tras la cirugía (12-60 meses) constatándose un HHS promedio de 91,8 puntos. Conclusión: El uso de cotilos modulares con revestimiento de metal trabecular de tantalio en cirugías de revisión acetabular presenta buenos resultados clínicos a corto plazo incluso en defectos óseos acetabulares superiores...

The metal tantalum in orthopedic applications / 生物医学工程学杂志

This paper describes the biological characteristics of the metal tantalum (Ts) and the application status of tantalum in artificial joints, bone necrosis, spine, defects of bone and other aspects of bone. The early clinical application results of tantalum in bone diseases were satisfactory, but it is necessary to do further study of tantalum in a deep going way, and further detailed comparison between the tantalum with other metals as orthopedics implants. The advantage of tantalum materials as orthopedic implants still needs to be verified by a great deal of clinical cases for a long period of time.