Base de dados : MEDLINE
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[PMID]:29424215
[Au] Autor:Chesnokova MG; Shalai VV; Kraus YA; Mironov AY; Blinova EG
[Ti] Título:[Informative indices of the biocorrosion activity for the determination of the character of the aggression ground].
[So] Source:Gig Sanit;95(6):513-7, 2016.
[Is] ISSN:0016-9900
[Cp] País de publicação:Russia (Federation)
[La] Idioma:rus
[Ab] Resumo:Underground corrosion is referred to the most difficult types of corrosion in connection with that it is multifactorial and differs in progressive dynamics of the participation of each parameter in the process of destruction of the metal. With the aim of the evaluation of the informativeness of the index of the biocorrosion activity caused by the influence of various factors to determine the character of the soil aggressiveness in the district of pipeline laying there was studied the complex of microbiological and physical-chemical indices). There was determined the amount of sulfur cycle bacteria (autotrophic thiobacteria and sulphate-reducing bacteria), the total concentration of sulfur and iron in the soil samples adjacent to the surface of the underground pipelines in the territory of the Khanty-Mansi Autonomous District of Yugra, and the ratio of these indices with a specific electrical resistance of the soil. There was established the predominance ofsamples with weak aggressiveness of the soil (55.17% of cases), with the criterion ofbiocorrosion soil activity of 2,44 ± 0,19. The results show significant differences in the thiobacteria content and mobile iron in the studied soil-ground samples. There was revealed a direct correlation of the average force of concentrations of identified bacteria and iron content in the soil. There was shown the necessity of the implementation of dynamic control and the development of methods of protection of metal structures to prevent biocorrosion in the design and in the process of the operation of the pipeline.
[Mh] Termos MeSH primário: Fenômenos Bioquímicos
Fenômenos Biofísicos
Microbiologia do Solo
Solo/química
[Mh] Termos MeSH secundário: Corrosão
Ecossistema
Bactérias Gram-Negativas Quimiolitotróficas/isolamento & purificação
Bactérias Redutoras de Enxofre/isolamento & purificação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Soil)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180210
[St] Status:MEDLINE


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[PMID]:29390311
[Au] Autor:Suwarsa O; Rahardjo RM; Sutedja E; Dharmadji HP; Hindritiani R; Gunawan H
[Ad] Endereço:Division of Allergy and Immunology, Department of Dermatology and Venereology, Faculty of Medicine, Universitas Padjadjaran-Dr. Hasan Sadikin Hospital, Bandung, Indonesia.
[Ti] Título:Systemic contact dermatitis due to corrosion of titanium-coated nickel and cobalt bone plate fixation: A case report.
[So] Source:Medicine (Baltimore);96(50):e9120, 2017 Dec.
[Is] ISSN:1536-5964
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:RATIONALE: Corrosion refers to the degradation of a material that occurs following its interaction with other substances in the environment. Corrosion of metallic substances into tissues may lead to inflammatory responses such as systemic contact dermatitis (SCD), a skin condition where an individual who has previously been sensitized to a particular allergen via the cutaneous route will subsequently react to same allergen via the systemic route. This condition occurs following exposure to allergens such as metals, medications, and certain food substances. In recent years, the use of metal plates for internal fixation has become increasingly common in bone fracture repairs. PATIENT CONCERNS: A 34-year-old Indonesian male presented with systemic erythema with itching 7 days following a bone plate fixation as a management for mandibular fracture. DIAGNOSES: Physical examination showed pruritic red macules, papules, and scales on almost his entire body, along with facial swelling. The patch test results revealed a positive reaction to nickel and cobalt. Therefore, the patient was diagnosed with SCD. INTERVENTIONS: The patient was treated with topical and systemic corticosteroids as well as bone plate removal. OUTCOME: After treatment, the eruption turned brown, the itching was resolved, and there were no facial swelling as well. LESSONS: This case report highlights the need to consider the occurrence of SCD in patients following bone plate fixation.
[Mh] Termos MeSH primário: Placas Ósseas
Dermatite de Contato/etiologia
Dermatite de Contato/terapia
Fixação Interna de Fraturas/instrumentação
Fraturas Mandibulares/cirurgia
[Mh] Termos MeSH secundário: Corticosteroides/uso terapêutico
Adulto
Cobalto
Corrosão
Remoção de Dispositivo
Seres Humanos
Masculino
Níquel
Testes do Emplastro
Titânio
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adrenal Cortex Hormones); 3G0H8C9362 (Cobalt); 7OV03QG267 (Nickel); D1JT611TNE (Titanium)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180203
[St] Status:MEDLINE
[do] DOI:10.1097/MD.0000000000009120


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[PMID]:29252750
[Au] Autor:Runner RP; Bellamy JL; Roberson JR
[Ad] Endereço:Department of Orthopaedics, Emory University, Atlanta, Georgia.
[Ti] Título:Gross Trunnion Failure of a Cobalt-Chromium Femoral Head on a Titanium Stem at Midterm Follow-up: A Report of 3 Cases.
[So] Source:JBJS Case Connect;6(4):e96, 2016 Oct-Dec.
[Is] ISSN:2160-3251
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:CASE: Three patients underwent uncomplicated primary total hip arthroplasty with cobalt-chromium femoral heads (36+5 mm) on titanium V40 tapers. At 6 to 9 years of follow-up, severe effects of corrosion at the trunnion were noted in all 3 patients, along with elevated levels of serum cobalt ions and normal levels of serum chromium ions. Gross trunnion failure, apparently caused by corrosion, required femoral stem revision in all of the patients. CONCLUSION: Decreased neck diameter, longer trunnion length, and large-sized cobalt-chromium heads are possible contributors to early failure after primary total hip arthroplasty due to trunnionosis. Surgeons should be mindful of trunnionosis as a cause of pain and a mechanism of failure following total hip arthroplasty, and serum metal ions should be monitored in these patients.
[Mh] Termos MeSH primário: Artroplastia de Quadril/instrumentação
Prótese de Quadril/efeitos adversos
Falha de Prótese/etiologia
[Mh] Termos MeSH secundário: Idoso
Corrosão
Seres Humanos
Masculino
Metais/sangue
Meia-Idade
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Metals)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180216
[Lr] Data última revisão:
180216
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171219
[St] Status:MEDLINE
[do] DOI:10.2106/JBJS.CC.16.00054


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[PMID]:28464615
[Au] Autor:Nygren H; Bigdeli N; Ilver L; Malmberg P
[Ad] Endereço:Department of Medical Chemistry and Cell Biology, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, POB 440, 40530 Gothenburg, Sweden.
[Ti] Título:Mg-corrosion, hydroxyapatite, and bone healing.
[So] Source:Biointerphases;12(2):02C407, 2017 05 02.
[Is] ISSN:1559-4106
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The different capacities of magnesium in the metallic form (Mg-metal) and magnesium oxide (MgO) to stimulate bone healing are possible clues in the search for products that may promote bone healing. Since both Mg-metal and MgO can be assumed to release comparable amounts of Mg ions during their reactions in the tissue where they have been implanted, it is of some importance to follow this process and analyze the resulting mineral formation in the tissue at the implantation site. Implants of MgO were inserted into rat tibia, and the bone healing was compared with sham-operated controls. Samples were taken after 1 week of healing and analyzed by histology, environmental scanning electron microscopy equipped with an energy dispersive x-ray spectroscopy analyzer, and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Callus bone was seen in sham-operated controls after 1 week of healing. Implantation of MgO impaired the callus bone formation by replacing bone with apparently mineralized areas, lacking osteocytes and were denoted, amorphous bodies. Elemental analysis showed increased levels of Ca (7.1%), P (3.7%), and Mg (0.2%) in the bone marrow of MgO-treated animals versus sham-operated controls Ca (2.4%), P (2.3%), and Mg (0.1%). The Ca content of the cortical bone was also significantly increased (Ca, 29% increase) in MgO-treated animals compared to sham-operated controls. The Ca content of the cortical bone of sham-operated animals was also significantly (p < 0.05) higher than the corresponding value of untreated animals, which means that the surgical trauma induces an altered composition of the bone mineral. The Ca/P ratio was 1.26-1.68, which is compatible with that of mineralized bone with different contents of organic materials. Analysis of bone sections using ToF-SIMS showed the presence of hydroxyapatite (HA) and MgCO in the bone marrow and in cortical bone. Analysis using x-ray photoelectron spectroscopy of Mg, MgO, and MgCO after incubation with cell culture medium (DMEM), in vitro, showed binding of CaPO at the Mg and MgO samples. The Ca/P ratio was 0.8, indicating a higher P content than that expected for HA. Exposure of human embryonic stem cells to Mg species preincubated in DMEM resulted in HA production by the cells. Thus, two sources of CaPO in the bone marrow of MgO-treated bone were defined, catalytic formation on Mg-species and synthesis from activated stem-cells. The presented data suggest that bone healing near Mg implants is congruent with the fracture healing of bone, boosted by high HA levels in the bone marrow. In this context, the different capacities of Mg-metal and MgO to catalyse the formation of HA can be important clues to their different bone promoting effects.
[Mh] Termos MeSH primário: Calo Ósseo/metabolismo
Osso Cortical/lesões
Osso Cortical/metabolismo
Durapatita/farmacologia
Consolidação da Fratura/efeitos dos fármacos
Óxido de Magnésio/farmacologia
[Mh] Termos MeSH secundário: Animais
Calo Ósseo/patologia
Linhagem Celular
Corrosão
Osso Cortical/patologia
Células-Tronco Embrionárias Humanas
Seres Humanos
Magnésio/farmacologia
Masculino
Teste de Materiais
Ratos
Ratos Sprague-Dawley
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
3A3U0GI71G (Magnesium Oxide); 91D9GV0Z28 (Durapatite); I38ZP9992A (Magnesium)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180201
[Lr] Data última revisão:
180201
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170504
[St] Status:MEDLINE
[do] DOI:10.1116/1.4982601


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[PMID]:29337992
[Au] Autor:Emran KM; Al-Harbi AK
[Ad] Endereço:Chemistry Department, College of Science, Taibah University, Al-Madinah Al-Monawarah, Saudi Arabia.
[Ti] Título:Outstanding resistance and passivation behaviour of new Fe-Co metal-metal glassy alloys in alkaline media.
[So] Source:PLoS One;13(1):e0187567, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The electrochemical behavior of the oxide layers on two metal-metal glassy alloys, Fe78Co9Cr10Mo2Al1 (VX9)and Fe49Co49V2 (VX50) (at.%), were studied using electrochemical techniques including electrochemical frequency modulation (EFM), electrochemical impedance spectroscopy (EIS) and cyclic polarization (CP) measurements. The morphology and composition of the alloy surfaces were investigated using X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The corrosion rate and surface roughness of both alloys increased as the concentration of NaOH in aqueous solution was raised. The presence of some protective elements in the composition of the alloys led to the formation of a spontaneous passive layer on the alloy surface. The higher resistance values of both alloys were associated with the magnitude of the dielectric properties of the passive films formed on their surfaces. Both alloys are classified as having outstanding resistance to corrosion, which results from the formation of a passive film that acts as an efficient barrier to corrosion in alkaline solution.
[Mh] Termos MeSH primário: Álcalis/química
Ligas/química
Cobalto/química
Vidro
Ferro/química
[Mh] Termos MeSH secundário: Corrosão
Microscopia de Força Atômica
Microscopia Eletrônica de Varredura
Espectroscopia Fotoeletrônica
Propriedades de Superfície
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Alkalies); 0 (Alloys); 3G0H8C9362 (Cobalt); E1UOL152H7 (Iron)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180129
[Lr] Data última revisão:
180129
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180117
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0187567


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[PMID]:29292339
[Au] Autor:Berstock JR; Whitehouse MR; Duncan CP
[Ad] Endereço:Musculoskeletal Research Unit, Bristol Medical School, 1st Floor Learning & Research Building, Southmead Hospital, Bristol BS10 5NB, UK.
[Ti] Título:Trunnion corrosion: what surgeons need to know in 2018.
[So] Source:Bone Joint J;100-B(1 Supple A):44-49, 2018 Jan.
[Is] ISSN:2049-4408
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:AIMS: To present a surgically relevant update of trunnionosis. MATERIALS AND METHODS: Systematic review performed April 2017. RESULTS: Trunnionosis accounts for approximately 2% of the revision total hip arthroplasty (THA) burden. Thinner (reduced flexural rigidity) and shorter trunnions (reduced contact area at the taper junction) may contribute to mechanically assisted corrosion, exacerbated by high offset implants. The contribution of large heads and mixed metallurgy is discussed. CONCLUSION: Identifying causative risk factors is challenging due to the multifactorial nature of this problem. Cite this article: 2018;100-B(1 Supple A):44-9.
[Mh] Termos MeSH primário: Artroplastia de Quadril/instrumentação
Prótese de Quadril
Falha de Prótese/etiologia
[Mh] Termos MeSH secundário: Corrosão
Seres Humanos
Desenho de Prótese
Reoperação
Fatores de Risco
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180104
[Lr] Data última revisão:
180104
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:180103
[St] Status:MEDLINE
[do] DOI:10.1302/0301-620X.100B1.BJJ-2017-0569.R1


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[PMID]:27770566
[Au] Autor:Rahim MI; Weizbauer A; Evertz F; Hoffmann A; Rohde M; Glasmacher B; Windhagen H; Gross G; Seitz JM; Mueller PP
[Ad] Endereço:Helmholtz Centre for Infection Research, Inhoffenstrasse 7, Braunschweig, 38124, Germany.
[Ti] Título:Differential magnesium implant corrosion coat formation and contribution to bone bonding.
[So] Source:J Biomed Mater Res A;105(3):697-709, 2017 03.
[Is] ISSN:1552-4965
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Magnesium alloys are presently under investigation as promising biodegradable implant materials with osteoconductive properties. To study the molecular mechanisms involved, the potential contribution of soluble magnesium corrosion products to the stimulation of osteoblastic cell differentiation was examined. However, no evidence for the stimulation of osteoblast differentiation could be obtained when cultured mesenchymal precursor cells were differentiated in the presence of metallic magnesium or in cell culture medium containing elevated magnesium ion levels. Similarly, in soft tissue no bone induction by metallic magnesium or by the corrosion product magnesium hydroxide could be observed in a mouse model. Motivated by the comparatively rapid accumulation solid corrosion products physicochemical processes were examined as an alternative mechanism to explain the stimulation of bone growth by magnesium-based implants. During exposure to physiological solutions a structured corrosion coat formed on magnesium whereby the elements calcium and phosphate were enriched in the outermost layer which could play a role in the established biocompatible behavior of magnesium implants. When magnesium pins were inserted into avital bones, corrosion lead to increases in the pull out force, suggesting that the expanding corrosion layer was interlocking with the surrounding bone. Since mechanical stress is a well-established inducer of bone growth, volume increases caused by the rapid accumulation of corrosion products and the resulting force development could be a key mechanism and provide an explanation for the observed stimulatory effects of magnesium-based implants in hard tissue. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 697-709, 2017.
[Mh] Termos MeSH primário: Implantes Experimentais
Magnésio
Células Mesenquimais Estromais/metabolismo
Coluna Vertebral/metabolismo
[Mh] Termos MeSH secundário: Animais
Linhagem Celular
Corrosão
Feminino
Magnésio/química
Magnésio/farmacocinética
Magnésio/farmacologia
Camundongos
Camundongos Endogâmicos BALB C
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
I38ZP9992A (Magnesium)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171225
[Lr] Data última revisão:
171225
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161023
[St] Status:MEDLINE
[do] DOI:10.1002/jbm.a.35943


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[PMID]:27776907
[Au] Autor:Kwon YM; Tsai TY; Leone WA; Liow MHL
[Ad] Endereço:Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
[Ti] Título:Sensitivity and Specificity of Metal Ion Levels in Predicting "Pseudotumors" due to Taper Corrosion in Patients With Dual Taper Modular Total Hip Arthroplasty.
[So] Source:J Arthroplasty;32(3):996-1000, 2017 03.
[Is] ISSN:1532-8406
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Currently, no serum metal ion threshold exists to identify adverse tissue reactions in total hip arthroplasty (THA) patients with taper corrosion. Our study aims to investigate the sensitivity and specificity of serum metal ions in detecting taper corrosion related pseudotumors in patients with dual taper modular THA. METHODS: A total of 148 patients with dual taper modular THA were investigated: (1) 90 patients with pseudotumors detected with metal artifact reduction sequence-magnetic resonance imaging (MARS-MRI) and (2) 58 patients without pseudotumors on MARS-MRI. Receiver operating characteristic curves were constructed to determine the sensitivity and specificity using different metal ion thresholds. The severity of intraoperative tissue damage was correlated with preoperative metal ion levels. RESULTS: Pseudotumor was associated with higher cobalt (5.0 µg/L vs 3.7 µg/L, P < .01) and Co/Cr ratio (6.0 vs 3.7, P < .01). The sensitivity and specificity for cobalt level of 2.8 µg/L and Co/Cr ratio of 3.8 in detecting taper corrosion-related pseudotumors on MARS-MRI was 88% and 32% and 70% and 50%, respectively. Higher intraoperative tissue damage grades demonstrated significantly higher Co/Cr ratios (8.6 vs 3.4, P = .03). CONCLUSION: Although metal ion levels alone should not be relied on as the sole parameter to determine revision surgery, cobalt level >2.8 µg/L and the Co/Cr ratio >3.8 are useful clinical diagnostic adjuncts in the systematic clinical evaluation for taper corrosion-related adverse tissue reactions in patients with dual modular taper THA.
[Mh] Termos MeSH primário: Artroplastia de Quadril/instrumentação
Granuloma de Células Plasmáticas/sangue
Granuloma de Células Plasmáticas/etiologia
Prótese de Quadril/efeitos adversos
Metais/sangue
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Artroplastia de Quadril/efeitos adversos
Cromo/sangue
Cobalto/sangue
Corrosão
Feminino
Granuloma de Células Plasmáticas/diagnóstico
Seres Humanos
Íons
Imagem por Ressonância Magnética
Masculino
Meia-Idade
Desenho de Prótese
Falha de Prótese
Curva ROC
Reoperação
Estudos Retrospectivos
Sensibilidade e Especificidade
Índice de Gravidade de Doença
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ions); 0 (Metals); 0R0008Q3JB (Chromium); 3G0H8C9362 (Cobalt)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171222
[Lr] Data última revisão:
171222
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161026
[St] Status:MEDLINE


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[PMID]:28963151
[Au] Autor:Langton DJ; Sidaginamale RP; Joyce TJ; Meek RD; Bowsher JG; Deehan D; Nargol AVF; Holland JP
[Ad] Endereço:Freeman Hospital, Northern Retrieval Registry, University Hospital of North Tees and Freeman Hospital, Newcastle Upon Tyne, UK.
[Ti] Título:A comparison study of stem taper material loss at similar and mixed metal head-neck taper junctions.
[So] Source:Bone Joint J;99-B(10):1304-1312, 2017 Oct.
[Is] ISSN:2049-4408
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:AIMS: We sought to determine whether cobalt-chromium alloy (CoCr) femoral stem tapers (trunnions) wear more than titanium (Ti) alloy stem tapers (trunnions) when used in a large diameter (LD) metal-on-metal (MoM) hip arthroplasty system. PATIENTS AND METHODS: We performed explant analysis using validated methodology to determine the volumetric material loss at the taper surfaces of explanted LD CoCr MoM hip arthroplasties used with either a Ti alloy (n = 28) or CoCr femoral stem (n = 21). Only 12/14 taper constructs with a rough male taper surface and a nominal included angle close to 5.666° were included. Multiple regression modelling was undertaken using taper angle, taper roughness, bearing diameter (horizontal lever arm) as independent variables. Material loss was mapped using a coordinate measuring machine, profilometry and scanning electron microscopy. RESULTS: After adjustment for other factors, CoCr stem tapers were found to have significantly greater volumetric material loss than the equivalent Ti stem tapers. CONCLUSION: When taper junction damage is identified during revision of a LD MoM hip, it should be suspected that a male taper composed of a standard CoCr alloy has sustained significant changes to the taper cone geometry which are likely to be more extensive than those affecting a Ti alloy stem. Cite this article: 2017;99-B:1304-12.
[Mh] Termos MeSH primário: Artroplastia de Quadril/métodos
Ligas de Cromo
Prótese de Quadril
Próteses Articulares Metal-Metal
[Mh] Termos MeSH secundário: Adulto
Idoso
Idoso de 80 Anos ou mais
Corrosão
Análise de Falha de Equipamento
Feminino
Seres Humanos
Masculino
Microscopia Eletrônica de Varredura
Meia-Idade
Desenho de Prótese
Falha de Prótese
Estresse Mecânico
Propriedades de Superfície
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171012
[Lr] Data última revisão:
171012
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:171001
[St] Status:MEDLINE
[do] DOI:10.1302/0301-620X.99B10.BJJ-2016-1005.R1


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[PMID]:28884275
[Au] Autor:Pourzal R; Hall DJ; Ehrich J; McCarthy SM; Mathew MT; Jacobs JJ; Urban RM
[Ad] Endereço:Department of Orthopedic Surgery, Rush University Medical Center, 1611 W Harrison Street, Suite 204-H, Chicago, IL, 60612, USA. robin_pourzal@rush.edu.
[Ti] Título:Alloy Microstructure Dictates Corrosion Modes in THA Modular Junctions.
[So] Source:Clin Orthop Relat Res;475(12):3026-3043, 2017 Dec.
[Is] ISSN:1528-1132
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Adverse local tissue reactions (ALTRs) triggered by corrosion products from modular taper junctions are a known cause of premature THA failure. CoCrMo devices are of particular concern because cobalt ions and chromium-orthophosphates were shown to be linked to ALTRs, even in metal-on-polyethylene THAs. The most common categories of CoCrMo alloy are cast and wrought alloy, which exhibit fundamental microstructural differences in terms of grain size and hard phases. The impact of implant alloy microstructure on the occurring modes of corrosion and subsequent metal ion release is not well understood. QUESTIONS/PURPOSES: The purpose of this study was to determine whether (1) the microstructure of cast CoCrMo alloy varies broadly between manufacturers and can dictate specific corrosion modes; and whether (2) the microstructure of wrought CoCrMo alloy is more consistent between manufacturers and has low implications on the alloy's corrosion behavior. METHODS: The alloy microstructure of four femoral-stem and three femoral-head designs from four manufacturers was metallographically and electrochemically characterized. Three stem designs were made from cast alloy; all three head designs and one stem design were made from wrought alloy. Alloy samples were sectioned from retrieved components and then polished and etched to visualize grain structure and hard phases such as carbides (eg, M C ) or intermetallic phases (eg, σ phase). Potentiodynamic polarization (PDP) tests were conducted to determine the corrosion potential (E ), corrosion current density (I ), and pitting potential (E ) for each alloy. Four devices were tested within each group, and each measurement was repeated three times to ensure repeatable results. Differences in PDP metrics between manufacturers and between alloys with different hard phase contents were compared using one-way analysis of variance and independent-sample t-tests. Microstructural features such as twin boundaries and slip bands as well as corrosion damage features were viewed and qualitatively assessed in a scanning electron microscope. RESULTS: We found broad variability in implant alloy microstructure for both cast and wrought alloy between manufacturers, but also within the same implant design. In cast alloys, there was no difference in PDP metrics between manufacturers. However, coarse hard phases and clusters of hard phases (mainly intermetallic phases) were associated with severe phase boundary corrosion and pitting corrosion. Furthermore, cast alloys with hard phases had a lower E than those without (0.46 V, SD 0.042; 0.53 V, SD 0.03, respectively; p = 0.015). Wrought alloys exhibited either no hard phases or numerous carbides (M C ). However, the corrosion behavior was mainly affected by lattice defects and banded structures indicative of segregations that appear to be introduced during bar stock manufacturing. Alloys with banding had a lower E (p = 0.008) and higher I (p = 0.028) than alloys without banding (-0.76 V, SD 0.003; -0.73 V, SD 0.009; and 1.14 × 10 mA/cm , SD 1.47 × 10 ; 5.2 × 10 mA/cm , SD 2.57 × 10 , respectively). Alloys with carbides had a slightly higher E (p = 0.046) than those without (-0.755 V, SD 0.005; -0.761 V, SD 0.004); however, alloys with carbides exhibited more severe corrosion damage as a result of phase boundary corrosion, hard phase detachment, and subsequent local crevice corrosion. CONCLUSIONS: The observed variability in CoCrMo alloy microstructure of both cast and wrought components in this study appears to be an important issue to address, perhaps through better standards, to minimize in vivo corrosion. The finding of the banded structures within wrought alloys is especially concerning because it unfavorably influences the corrosion behavior independent of the manufacturer. The findings suggest that a homogeneous alloy microstructure with a minimal hard phase fraction exhibits more favorable corrosion behavior within the in vivo environment of modular taper junctions, thus lowering metal ion release and subsequently the risk of ALTRs to corrosion products. Also, the question arises if hard phases fulfill a useful purpose in metal-on-polyethylene bearings, because they may come with a higher risk of phase boundary corrosion and pitting corrosion and the benefit they provide by adding strength is not needed (unlike in metal-on-metal bearings). CLINICAL RELEVANCE: Implant failure resulting from corrosion processes within modular junctions is a major concern in THA. Our results suggest that implant alloy microstructure is not sufficiently standardized and may also dictate specific corrosion modes and subsequent metal ion release.
[Mh] Termos MeSH primário: Artroplastia de Quadril/instrumentação
Ligas de Cromo/química
Articulação do Quadril/cirurgia
Prótese de Quadril
Polietileno/química
Falha de Prótese
[Mh] Termos MeSH secundário: Artroplastia de Quadril/efeitos adversos
Corrosão
Remoção de Dispositivo
Análise de Falha de Equipamento
Seres Humanos
Desenho de Prótese
Fatores de Risco
Propriedades de Superfície
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chromium Alloys); 9002-88-4 (Polyethylene)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171118
[Lr] Data última revisão:
171118
[Sb] Subgrupo de revista:AIM; IM
[Da] Data de entrada para processamento:170909
[St] Status:MEDLINE
[do] DOI:10.1007/s11999-017-5486-3



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