oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
Treatment of fractures of the tibial diaphysis using external fixator compared with locked intramedullary nails Tratamento das fraturas diafisárias da tíbia com fixador externo comparado com a haste intramedular bloqueada
Rodrigo Tavares Cardozo,Luís Gustavo Silva,Leandro Augusto Bragante,Murilo Ant?nio Rocha
Revista Brasileira de Ortopedia , 2013,
Abstract: OBJECTIVE: To compare efficiency of external fixator in modular form with unilateral and uniplanar intramedullary locked seeking definitive treatment of fractures of the tibia diaphysis. METHODS: Orthopedic surgical treatments were compared to 50 patients with definite diafisária fracture of the tibia, through the use of the external fixator, modular and intramedullary locked. The fractures were treated at emergency hospital school of Orthopedics and Traumatology service in the period from January 2007 to January 2011, with a variation of 15 to 48 weeks. RESULTS: this study has proven functional results and excellent consolidation when locked intramedullary rods were used and the versatility and speed of application of external fixator reaching the necessary stabilization of bony fragments. Consolidation of fractures was obtained in 95 cases when using the intramedullary locked and 90 cases undergoing external fixation. CONCLUSIONS: the definitive treatment of tibial diaphysis fractures by external fixator modular presented themselves as valid alternative treatment in patients who could not be submitted for early conversion to internal osteosynthesis or when the intramedullary nails are not available to the surgeon. OBJETIVO: Comparar a eficiência de fixador externo modular na forma uniplanar e unilateral com haste intramedular bloqueada (HIB) buscando tratamento definitivo das fraturas diafisárias da tíbia. MéTODOS: Foram comparados os tratamentos cirúrgicos ortopédicos definitivos de 50 pacientes com fratura diafisária da tíbia, por meio do uso do fixador externo modular e da haste intramedular bloqueada. As fraturas foram tratadas no setor de emergência de um hospital-escola pelo servi o de ortopedia e traumatologia de janeiro de 2007 a janeiro de 2011, com varia o de 15 a 48 semanas. RESULTADOS: Este estudo comprovou resultados funcionais e de consolida o excelentes quando usada a haste intramedular bloqueada e a versatilidade e rapidez na aplica o do fixador externo atingindo a estabiliza o necessária dos fragmentos ósseos. Foi obtida a consolida o das fraturas em 95% dos casos quando usamos a haste intramedular bloqueada e 90% dos casos submetidos à fixa o externa. CONCLUS ES: O tratamento definitivo das fraturas diafisárias da tíbia por meio do fixador externo modular apresentou-se como uma op o válida de tratamento em pacientes que n o puderam ser submetidos à convers o precoce para osteossíntese interna ou quando as hastes intramedulares n o est o disponíveis para o cirurgi o.
Factorial Study of Compressive Mechanical Properties and Primary In Vitro Osteoblast Response of PHBV/PLLA Scaffolds  [PDF]
Naznin Sultana,Tareef Hayat Khan
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/656914
Abstract: For bone tissue regeneration, composite scaffolds containing biodegradable polymers and nanosized osteoconductive bioceramics have been regarded as promising biomimetic systems. Polymer blends of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and poly(L-lactic acid) (PLLA) can be used as the polymer matrix to control the degradation rate. In order to render the scaffolds osteoconductive, nano-sized hydroxyapatite (nHA) particles can be incorporated into the polymer matrix. In the first part of this study, a factorial design approach to investigate the influence of materials on the initial compressive mechanical properties of the scaffolds was studied. In the second part, the protein adsorption behavior and the attachment and morphology of osteoblast-like cells (Saos-2) of the scaffolds in vitro were also studied. It was observed that nHA incorporated PHBV/PLLA composite scaffolds adsorbed more bovine serum albumin (BSA) protein than PHBV or PHBV/PLLA scaffolds. In vitro studies also revealed that the attachment of human osteoblastic cells (SaOS-2) was significantly higher in nHA incorporated PHBV/PLLA composite scaffolds. From the SEM micrographs of nHA incorporated PHBV/PLLA composite scaffolds seeded with SaOS-2 cells after a 7-day cell culture period, it was observed that the cells were well expanded and spread in all directions on the scaffolds. 1. Introduction In scaffold-based tissue engineering (TE), scaffolds play several important roles. Scaffold material and scaffold fabrication techniques should be selected carefully as the scaffold properties are crucial to determine the success of a TE approach [1, 2]. One of the basic requirements for polymer-based scaffolds is that the scaffolds should have controllable porous architecture that can allow cell migration, attachment, and growth, leading to tissue regeneration. The degradation product(s) of scaffolds should be non-toxic and easily taken up or excreted via metabolic pathways. Scaffolds should have sufficient mechanical strength to maintain structural integrity during culture. Some of the commonly used biodegradable polymers that are used as scaffold materials include poly(glycolic acid) (PGA), poly(l-lactic acid) (PLLA), and their copolymer poly(lactic acid-co-glycolic acid) (PLGA) [2]. Poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV), which is a natural, biodegradable polymer, possesses good biocompatibility, also being used to made into TE scaffolds. The in vivo degradation product of PHBV is a normal constituent of human blood [2]. PHBV has been investigated for tissue engineering
Imobiliza o de fraturas femorais em gatos usando pino intramedular conectado ou n o ao fixador esquelético externo  [cached]
Rahal Sheila Canevese,Garib Maria Isabel,Matsubara Fabiana Mitie,Vulcano Luiz Carlos
Ciência Rural , 2004,
Abstract: O trabalho teve por objetivo comparar a consolida o óssea e a fun o do membro, em 18 gatos com fraturas transversas femorais tratadas com pino intramedular e fixador esquelético externo tipo Ia (grupo I, n=9) ou com pino intramedular associado ao fixador externo em uma configura o "tie-in" (grupo II, n=9). Independente da configura o utilizada, após a remo o dos implantes, todos os animais apresentaram fun o normal do membro operado. N o houve diferen a entre os grupos em rela o à densidade mineral óssea do calo externo mensurada pela densitometria óptica por imagens radiográficas. O tempo para consolida o foi significativamente maior para as fraturas tratadas com pino intramedular e fixador tipo Ia. As fraturas que receberam a configura o "tie-in" tiveram menos prolifera o de calo ósseo.
Estudo anat mico da via de acesso suprapatelar lateral para a haste intramedular bloqueada na fratura da tíbia Anatomical study on the lateral suprapatellar access route for locked intramedullary nails in tibial fractures
Italo Scanavini Cerqueira,Pedro Araujo Petersen,Rames Mattar Júnior,Jorge dos Santos Silva
Revista Brasileira de Ortopedia , 2012, DOI: 10.1590/s0102-36162012000200005
Abstract: OBJETIVO: A haste intramedular (HIM) é o padr o ouro no tratamento das fraturas diafisárias da tíbia. Uma das complica es frequentes é a dor no joelho após o procedimento. MéTODOS: Vias alternativas, como a suprapatelar para a introdu o da haste como op o para evitar a dor no joelho no período pós-operatório tardio, têm sido estudadas. A quest o é se nesta nova via ocorre alguma les o às estruturas intra-articulares do joelho. RESULTADOS: Este estudo analisa a via suprapatelar e o risco para as estruturas adjacentes através da sua reprodu o em 10 joelhos de cinco cadáveres. CONCLUS O: Foi visto facilidade para a localiza o do ponto de entrada por esta via, lesando apenas a gordura de Hoffa. Em três dos nossos casos houve les o da superfície condral, sendo um obstáculo de difícil transposi o e indicando necessidade de fabrica o de material específico para minimizar a les o das estruturas intra-articulares por essa via. OBJECTIVE: Intramedullary nails are the gold standard for treating tibial shaft fractures. Knee pain is a frequent complication after the procedure. Alternative routes such as the suprapatellar approach for nail insertion are seen as an option for avoiding late postoperative knee pain. The question is whether this approach might give rise to any injury to intra-articular structures of the knee. METHODS: This study analyzed the suprapatellar approach and the risk to adjacent structures by reproducing it in 10 knees of five cadavers. RESULTS: This approach was seen to make it easy to locate the entry point, with lesions only occurring in the Hoffa fat. In three of our cases, there were lesions of the chondral surface, which is an obstacle that is difficult to overcome. CONCLUSION: There is a need to develop specific material to minimize injury to intra-articular structures when using this route.
Sistemas osso-implante ex vivo utilizando haste intramedular polimérica para imobiliza??o de fraturas femorais em bovinos jovens
Spadeto Junior, Odael;Rodrigues, Luciano Brito;Carvalho, Wellington Tadeu Vilela;Moreira, Deliene de Oliveira;De Marval, Cyril Alexandre;Costa, Cláudio Gomes da;Alves, Geraldo Eleno Silveira;Las Casas, Estevam Barbosa de;Faleiros, Rafael Resende;
Ciência Rural , 2011, DOI: 10.1590/S0103-84782011000200020
Abstract: the development of new devices using available and low cost materials may be an useful alternative for the treatment of long bone fractures in large animals. the aim of this study was to evaluate the mechanical strength of young bovine femur with diaphyseal fracture fixed with different polymeric intramedullary nails. bending and compression tests using a universal machine were carried out in 4 distinct groups of 6 femurs from young calves. in one of the groups bones were intact while in the other three fractured bones were fixed using an intramedullary nail made of polypropylene, polyacetal or polyamide (one for each group). considering bending and compression tests together, none of the used polymers offered strength to the fractured bones similar to the intact ones. the agreement of this findings with those from previous published in vivo results indicates that the employed ex vivo methods for mechanical assays may be useful in the search of stronger materials to be used in development of new devices.
Estudo prospectivo e randomizado de pacientes com fraturas expostas da diáfise do fêmur submetidos a osteossíntese com placa e haste intramedular bloqueada a foco aberto
Ferracini, Antonio Marcos;Faloppa, Flavio;Daltro, Gildasio de Cerqueira;Crisóstomo Júnior, Dalton de Castro;Reis, Fernando Baldy dos;Belotti, Jo?o Carlos;
Acta Ortopédica Brasileira , 2008, DOI: 10.1590/S1413-78522008000200008
Abstract: we assessed the complications and treatment outcomes in a prospective and randomized study of two osteosynthesis techniques in open femoral shaft fractures. between january 2002 and april 2004, 40 patients with open fractures of the femoral shaft were assessed, with 20 being treated with open reamed intramedullary locked nail and 20 with plate. twenty-six (65%) fractures were classified as gustilo type -i open fractures; ten (25%) as type ii and four (10%), as type iiia. there were 21 blunt injuries and 19 gunshot injuries. three patients were excluded from the final assessment. complications were observed in 12 (32.4%) patients, 4 in the plate group and 8 in the nail group. reamed intramedullary locked nail resulted in two deep infections (10%), two superficial infections (10%), and one nonunion (5%). with plate techniques, we had one deep infection associated to nonunion (5,8%) and one superficial infection (5.8%). good and excellent outcomes were found in 28 fractures (75.7%), fair (7.5%) in three cases, and poor (15%) in six, according to thorensen?s criteria. in this study, the stabilization with plate results in lower complications rate when compared to the open intramedullary nail, although with no statistical significance.
Estudo comparativo prospectivo e randomizado entre o tratamento cirúrgico das fraturas diafisárias do úmero com placa em ponte e haste intramedular bloqueada (análise preliminar)
Benegas, Eduardo;Amódio, Daniel Tasseto;Correia, Luiz Filipe Marques;Malavolta, Eduardo Angeli;Ramadan, Lucas Busnardo;Ferreira Neto, Arnaldo Amado;Zumiotti, Arnaldo Valdir;
Acta Ortopédica Brasileira , 2007, DOI: 10.1590/S1413-78522007000200006
Abstract: the treatment of the great majority of humeral shaft fractures is conservative. absolute indications (i.e., vascular injury) and relative indications (i.e., primary nervous palsy) for surgical treatment are well established by literature. the two most used methods for that purpose - the self - compression plate and the locked intramedullary nail - have already been comparatively studied. however, there are no studies comparing intramedullary nails to the bridging plate, therefore, this is the objective of the present study.
Fraturas da extremidade distal da tíbia tratadas pela haste intramedular e placa em ponte: compara??o do tempo de exposi??o à radia??o nos dois métodos
Labronici, Pedro José;Lyra, Fábio Soares;Moreira Junior, Ildeu Leite;Hoffmann, Rolix;Franco, José Sergio;Louren?o, Paulo Roberto Barbosa de Toledo;Labronici, Gustavo José;
Revista Brasileira de Ortopedia , 2010, DOI: 10.1590/S0102-36162010000200004
Abstract: objective: to compare the exposure time to radiation in patients with distal third fractures of the tibia treated with intramedullary nail and bridge plate. methods: in 33 fractures intramedullary nails were used, and in 41 fractures plates were used. in the intramedullary nail group, according to the ao classification, 14 patients had type a fractures, 15 patients had type b fractures and four had type c fractures. twelve patients had closed fractures and 21 had open fractures. in the plate group, 10 patients had type a fractures, 22 patients had type b fractures and nine had type c fractures. 27 patients had closed fractures and 14 had open fractures. results: a significant difference was observed in exposure time to radiation between the patients treated with the intramedullary nail and the plate (p = 0.0001). the group treated with the intramedullary nail had a significantly higher exposure time to the radiation than the group treated with the plate. comparing the type of fracture (a, b and c), it was observed that there is no considerable difference in exposure time to radiation between the intramedullary nail technique (p = 0.19) and the plate technique (p = 0.80). conclusion: fractures of distal third of the tibia treated with intramedullary nail show considerably higher exposure time to radiation than fractures treated with the bridge plate, independent of fracture type.
Improvement of PHBV Scaffolds with Bioglass for Cartilage Tissue Engineering  [PDF]
Jun Wu, Ke Xue, Haiyan Li, Junying Sun, Kai Liu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0071563
Abstract: Polymer scaffold systems consisting of poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) have proven to be possible matrices for the three-dimensional growth of chondrocyte cultures. However, the engineered cartilage grown on these PHBV scaffolds is currently unsatisfactory for clinical applications due to PHBV’s poor hydrophilicity, resulting in inadequate thickness and poor biomechanical properties of the engineered cartilage. It has been reported that the incorporation of Bioglass (BG) into PHBV can improve the hydrophilicity of the composites. In this study, we compared the effects of PHBV scaffolds and PHBV/BG composite scaffolds on the properties of engineered cartilage in vivo. Rabbit articular chondrocytes were seeded into PHBV scaffolds and PHBV/BG scaffolds. Short-term in vitro culture followed by long-term in vivo transplantation was performed to evaluate the difference in cartilage regeneration between the cartilage layers grown on PHBV and PHBV/BG scaffolds. The results show that the incorporation of BG into PHBV efficiently improved both the hydrophilicity of the composites and the percentage of adhered cells and promoted cell migration into the inner part the constructs. With prolonged incubation time in vivo, the chondrocyte-scaffold constructs in the PHBV/BG group formed thicker cartilage-like tissue with better biomechanical properties and a higher cartilage matrix content than the constructs in the PHBV/BG group. These results indicate that PHBV/BG scaffolds can be used to prepare better engineered cartilage than pure PHBV.
CRYSTALLIZATION BEHAVIOR OF INCOMPATIBLE PHBV/PS AND PHBV/PMMA CRYSTALLINE/AMORPHOUS BLENDS
不相容PHBV/PS、PHBV/PMMA结晶/非晶共混体系的结晶行为研究

YANG Jian,WANG Zongbao,WU Yang,WU Xiangfa,GU Qun,
杨建
,王宗宝,伍洋,吴香发,顾群

高分子学报 , 2010,
Abstract: The crystallization behaviors of incompatible poly(3-hydroxybutyrate-co-3-hydroxyvalerate)(PHBV)/PS,PHBV/PMMA crystalline/amorphous blends with different ratios and different crystallization temperatures were investigated,with particular emphasis on the effect of amorphous components,such as PS or PMMA,on the morphology of PHBV ring-banded spherulites.PHBV ring-banded spherulites with slightly fuzzy bands were obtained when the content of PHBV in blends was 75%,which was similar to pure PHBV.Petal shaped spherulites were obtained at the crystallization temperature slightly lower than Tg of amorphous components when the content of PHBV in blends was 50%.When the content of PHBV in blends was 25%,irregular crystal morphologies were obtained in PHBV/PS blends,whereas no crystal was observed under POM in PHBV/PMMA blends.In the incompatible blends,the dispersion state and blends ratio of amorphous content had the decisive effect on the formation of PHBV ring-banded spherulites:ring-banded spherulites developed only at low crystallization temperatures when amorphous component content was high,and ring-banded spherulites generated at a wide range of crystallization temperature when amorphous component content was low,whereas the effect of amorphous content on the growth of lamellae at the front of spherulites was the main cause of the formation of petal shaped spherulites.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.