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Open fractures often require complex treatments, especially those with joint involvement or critical bone defects. Managing both combined injuries present even greater challenges and is not without complications. We present the case of a young patient with an open fracture of the femoral condyle and loss of bone stock in the articular surface. In this case, a combined osteosynthesis approach was employed, utilizing cannulated screws and a femoral condyle arthroplasty with bone cement as a salvage measure, allowing a favorable clinical and functional outcome at the 3-year follow-up. This technique serves as a simple, reproducible, and cost-effective alternative for transient or potentially definitive management in such cases.

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PURPOSE: To compare the incidence of perioperative thromboembolic events in femoral neck fracture (FNF) patients treated with hybrid total hip arthroplasty (THA) with intraoperative unfractionated heparin (UFH) versus a control group without intraoperative UFH before femoral component cementation. METHODS: We compared 139 cases without UFH (group A) versus 134 who received 10 UI/kg UFH (group B). Indication of UFH before cementation depended on the preferences of the anaesthesiologists in each case. We assessed intraoperative bone cement implantation syndrome (BCIS) and 30-day thromboembolic events, and 90-day and 1-year mortality. BCIS was classified as per Donaldson et al.'s classification according to the degree of hypotension, arterial desaturation or loss of consciousness. RESULTS: BCIS was observed in 51 (18%) cases, including 37 (13%) grade 1 and 14 (5%) grade 2. Forty-seven BCISs (35%) were observed in group B and 4 (3%) in group A (p < 0.001). Multivariate regression showed that intraoperative UFH (OR = 18, CI 95% 6-52) and consumption of oral anticoagulants (OR = 3.3, CI 95% 1-10) increased the risk of BCIS. Five patients further developed a 30-day pulmonary embolism in group B, while 2 presented this complication in group A (p = 0.231). No association between BCIS and 30-day thromboembolic events was found (p = 0.62). 90-day (1% each, p = 0.98) and 1-year (2% vs. 3%, p = 0.38) mortality were similar. CONCLUSIONS: BCIS was a frequent finding in FNF patients treated with hybrid THA. We found a paradoxically significant increase in BCIS with the use of UFH. Heparin did not seem to prevent BCIS, other thromboembolic events and mortality in this group of patients.

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New bone cement type that combines Sr2 + /Mg2 + or Sr2 + /Zn2 + co-substituted nano-hydroxyapatite (n-HAs) with calcium phosphate dibasic and chitosan/gelatin polymers was developed to increase adhesion and cellular response. The cements were physicochemically described and tested in vitro using cell cultures. All cements exhibited quite hydrophilic and had high washout resistance. Cement releases Ca2 + , Mg2 + , Sr2 + , and Zn2 + in concentrations that are suitable for osteoblast proliferation and development. All of the cements stimulated cell proliferation in fibroblasts, endothelial cells, and osteoblasts, were non-cytotoxic, and produced apatite. Cements containing co-substituted n-HAs had excellent cytocompatibility, which improved osteoblast adhesion and cell proliferation. These cements had osteoinductive potential, stimulating extracellular matrix (ECM) mineralization and differentiation of MC3T3-E1 cells by increasing ALP and NO production. The ions Ca2 + , Mg2 + , Zn2 + , and Sr2 + appear to cooperate in promoting osteoblast function. The C3 cement (HA-SrMg5%), which was made up of n-HA co-substituted with 5 mol% Sr and 5 mol% Mg, showed exceptional osteoinductive capacity in terms of bone regeneration, indicating that this new bone cement could be a promising material for bone replacement.

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Most genetic diseases affect purebred animals and are inherited as recessive genes. Cranioschisis refers to dysraphism, which occurs in the midline of the skull due to failure to close the cranial symphysis, which can lead to herniation of the meninges filled with cerebrospinal fluid (meningocele), where there is usually a projection of the meningeal tissue. Diagnosis is performed based on clinical examination, characteristic anatomopathological data, and complementary imaging tests. The surgical approach for correction of cranioschisis is the only described as a therapeutic solution and is indicated in cases in which the cranial synthesis defect does not allow for brain protrusion and there is only the occurrence of meningocele, in addition to the absence of severe signs of neurological alteration. This paper reports a case of the use of polymethylmethacrylate (PMMA) plaque to treat cranioschisis associated with meningocele in a Girolando heifer. The surgical opening of the frontonasal sacculation allowed draining a total liquid content of 488 mL, inspection, and suture of the envelope membrane. APMMA plaque, molded to the bone surface and anchored in the adjacent soft tissue, was used to cover the evidenced frontonasal bone opening. Despite the unfavorable prognosis of the disease, the cranioplasty surgery for the treatment of cranioschisis associated with meningocele using PMMA plaque obtained satisfactory results relative to the quality and maintenance of this animal's life, evaluated at 19 months postoperatively.(AU)

A maioria das doenças genéticas acometem animais de raça pura e herdados como genes recessivos.Acraniosquise refere-se à disrafia, que acontece na linha média do crânio pelo não fechamento da sínfise craniana, podendo levar a herniação das meninges repletas de líquido cefalorraquidiano (meningocele), onde geralmente existe projeção do tecido meningeal. O diagnóstico é realizado a partir do exame clínico, dados anatomopatológicos característicos e através da realização de exames complementares de imagem. Como solução terapêutica, a abordagem cirúrgica para correção das craniosquises é a única descrita, e é indicada em casos em que o defeito de síntese craniana não permita a protrusão encefálica e exista a ocorrência apenas da meningocele, além da inexistência de sinais graves de alteração neurológica. O artigo relata um caso de uso de placa de polimetilmetacrilato (PMMA) no tratamento de craniosquise associada à meningocele em uma bezerra Girolando. Instituiu-se a abertura cirúrgica da saculação fronto-nasal, permitindo a drenagem de conteúdo líquido total de 488 mL, inspeção e rafia de membrana envoltória. Para recobrimento da abertura óssea fronto-nasal evidenciada, utilizou-se uma placa de polimetilmetacrilato (PMMA), moldada à superfície óssea e ancorada em tecido mole adjacente. Concluiu-se que, apesar do prognóstico desfavorável da enfermidade, a cirurgia de cranioplastia para tratamento de craniosquise associada à meningocele, com a utilização de placa de PMMA, neste caso, obteve resultados satisfatórios em relação a qualidade e manutenção da vida deste animal, avaliando-se em 19 meses pós-operatório.(AU)

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This study evaluated the formation of a Masquelet-induced membrane created through the formation of segmental bone defects in the radii of 15 healthy domestic chickens. When the chickens were in a surgical plane of anesthesia, a 1.5-cm segmental bone defect was produced in the left radius, which was subsequently filled with a bone cement spacer during its pasty polymerization phase. The bone defects were evaluated through radiographic imaging immediately after surgery and at 7, 15, 21, and 30 days after the creation of the bone defect. Five birds were euthanatized at 15, 21, and 30 days postoperatively for histological evaluation of the bone defect site. Immediate postoperative radiographic examination of the radii showed the presence of bone cement, which occupied the segmental bone defect. Thirty days after the surgical procedure, the presence of new bone formation at the fractured extremities was evident in the 5 remaining chickens. Histologically, the induced-membrane had 3 distinct zones at 15 days postoperatively, including 1 cell layer in contact with the bone cement spacer, 1 layer with collagen fibers, and 1 layer in contact with muscle, which was composed of disorganized connective tissue, active fibroblasts, and blood vessels. Twenty-one days after surgery, the zones were less defined, and there were metaplastic areas comprising cartilage and bone. Postoperative, diffuse mineralization of the membrane was observed 30 days after the surgical procedure. Formation of the induced membrane was observed during all periods of evaluation. The best histological characteristics for the Masquelet-induced membrane were detected 15 days after the formation of the bone defect, suggesting this would be the optimal time for second-stage surgery for bone reconstruction.

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Acrylic bone cements (ABC) are widely used in orthopedics for joint fixation, antibiotic release, and bone defect filling, among others. However, most commercially available ABCs exhibit a lack of bioactivity and are susceptible to infection after implantation. These disadvantages generate long-term loosening of the prosthesis, high morbidity, and prolonged and expensive treatments. Due to the great importance of acrylic bone cements in orthopedics, the scientific community has advanced several efforts to develop bioactive ABCs with antibacterial activity through several strategies, including the use of biodegradable materials such as chitosan (CS) and nanostructures such as graphene oxide (GO), with promising results. This paper reviews several studies reporting advantages in bioactivity and antibacterial properties after incorporating CS and GO in bone cements. Detailed information on the possible mechanisms by which these fillers confer bioactive and antibacterial properties to cements, resulting in formulations with great potential for use in orthopedics, are also a focus in the manuscript. To the best of our knowledge, this is the first systematic review that presents the improvement in biological properties with CS and GO addition in cements that we believe will contribute to the biomedical field.

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Bacterial infections are a common complication after total joint replacements (TJRs), the treatment of which is usually based on the application of antibiotic-loaded cements; however, owing to the increase in antibiotic-resistant microorganisms, the possibility of studying new antibacterial agents in acrylic bone cements (ABCs) is open. In this study, the antibacterial effect of formulations of ABCs loaded with graphene oxide (GO) between 0 and 0.5 wt.% was evaluated against Gram-positive bacteria: Bacillus cereus and Staphylococcus aureus, and Gram-negative ones: Salmonella enterica and Escherichia coli. It was found that the effect of GO was dependent on the concentration and type of bacteria: GO loadings ≥0.2 wt.% presented total inhibition of Gram-negative bacteria, while GO loadings ≥0.3 wt.% was necessary to achieve the same effect with Gram-positives bacteria. Additionally, the evaluation of some physical and mechanical properties showed that the presence of GO in cement formulations increased wettability by 17%, reduced maximum temperature during polymerization by 19%, increased setting time by 40%, and increased compressive and flexural mechanical properties by up to 17%, all of which are desirable behaviors in ABCs. The formulation of ABC loading with 0.3 wt.% GO showed great potential for use as a bone cement with antibacterial properties.

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Despite the potential of acrylic bone cement (ABC) loaded with chitosan (CS) for orthopedic applications, there are only a few in vitro studies of this composite with CS loading ≤ 15 wt.% evaluated in bioactivity tests in simulated body fluid (SBF) for duration > 30 days. The purpose of the present work was to address this shortcoming of the literature. In addition to bioactivity, a wide range of cement properties were determined for composites with CS loading ranging from 0 to 20 wt.%. These properties included maximum exotherm temperature (Tmax), setting time (tset), water contact angle, residual monomer content, flexural strength, bending modulus, glass transition temperature, and water uptake. For cement with CS loading ≥ 15 wt.%, there was an increase in bioactivity, increase in biocompatibility, decrease in Tmax, increase in tset, all of which are desirable trends, but increase in residual monomer content and decrease in each of the mechanical properties, with each of these trends, were undesirable. Thus, a composite with CS loading of 15 wt.% should be further characterized to explore its suitability for use in low-weight-bearing applications, such as bone void filler and balloon kyphoplasty.

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ABSTRACT Objective: To evaluate facial profile changes promoted by polymethyl methacrylate (PMMA) cement graft to reduce excessive gingival display due to hyperactivity of the elevator muscles of the upper lip during smiling. Methods: Eleven patients (all females, age range: 20 to 43 years) presenting gingival smile that were treated with PMMA cement grafts in a private clinic were selected for this retrospective study. Three angular and ten linear cephalometric facial profile measurements were performed preoperatively (baseline, T1) and at least 6 months postoperatively (T2). Differences between T1 and T2 were verified by Wilcoxon test, and the correlation between the thickness of the graft and facial profile changes was statistically evaluated by Spearman's Coefficient test. The significance level was set at p< 0.05. Results: The nasolabial angle (p= 0.03) and the labial component of the nasolabial angle showed statistically significant differences (p= 0.04), with higher values in T2. No correlations were found between the graft thickness and the statistically significant facial profile changes (p> 0.05). Conclusions: The PMMA bone cement graft projected the upper lip forward, thereby increasing the nasolabial angle without affecting the nasal component. No correlations between the graft thickness and the facial profile changes were detected.

RESUMO Objetivo: Avaliar as alterações do perfil facial promovidas pelo enxerto de cimento de polimetilmetacrilato (PMMA) para redução da exposição gengival excessiva devida à hiperatividade dos músculos elevadores do lábio superior durante o sorriso. Métodos: Onze pacientes (todos do sexo feminino, faixa etária de 20 a 43 anos) com sorriso gengival, tratados com enxerto de cimento de PMMA em clínica privada, foram selecionados para este estudo retrospectivo. Três medidas cefalométricas angulares e dez lineares do perfil facial foram realizadas no pré-operatório (T1) e com pelo menos seis meses de pós-operatório (T2). As diferenças entre T1 e T2 foram verificadas pelo teste de Wilcoxon, e a correlação entre a espessura do enxerto e as alterações do perfil facial foi avaliada estatisticamente pelo Coeficiente de Spearman. O nível de significância foi estabelecido em p< 0,05. Resultados: o ângulo nasolabial (p= 0,03) e o componente labial do ângulo nasolabial apresentaram diferenças estatisticamente significativas (p= 0,04), com maiores valores em T2. Não foram encontradas correlações estatisticamente significativas (p> 0,05) entre a espessura do enxerto e as alterações do perfil facial. Conclusões: O enxerto de cimento ósseo de PMMA projetou discretamente o lábio superior, aumentando o ângulo nasolabial sem afetar o componente nasal. Não foram detectadas correlações entre a espessura do enxerto e as alterações do perfil facial.

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In this research, damage in bone cements that were prepared with core-shell nanoparticles was monitored during four-point bending tests through an analysis of acoustic emission (AE) signals. The core-shell structure consisted of poly(butyl acrylate) (PBA) as rubbery core and methyl methacrylate/styrene copolymer (P(MMA-co-St)) as a glassy shell. Furthermore, different core-shell ratios 20/80, 30/70, 40/60, and 50/50 were prepared and incorporated into the solid phase of the bone cement formulation at 5, 10, and 15 wt %, respectively. The incorporation of a rubbery phase into the bone cement formulation decreased the bending strength and bending modulus. The AE technique revealed that the nanoparticles play an important role on the fracture mechanism of the bone cement, since a higher amount of AE signals (higher amplitude and energy) were obtained from bone cements that were prepared with the nanoparticles in comparison with those without nanoparticles (the reference bone cement). The SEM examination of the fracture surfaces revealed that all of the bone cement formulations exhibited stress whitening, which arises from the development of crazes before the crack propagation. Finally, the use of the AE technique and the fracture surface analysis by SEM enabled insight into the fracture mechanisms that are presented during four-point bending test of the bone cement containing nanoparticles.

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Vertebral and spinal cord trauma are common conditions in small animal practice and often result in vertebral fractures/luxation (VFL) with concomitant spinal cord laceration, concussion, compression, or ischemia. These lesions have several clinical presentations that may vary from moderate to severe pain and partial to total loss of motor, sensory, and visceral functions, which may result in death or euthanasia. Our purpose is to describe five cases (four dogs and one cat) of complications secondary to the use of bone cement for vertebral stabilization. The patients, between five months and four years of age and weighing between 1.4 and 12.2 kg, were referred to the Small Animal Orthopedics and Traumatology Service of the Veterinary Hospital of the College of Veterinary Medicine and Animal Science of the University of São Paulo. They had a history of post-operatory polymethyl methacrylate (PMMA) reactions (such as drainage or cement exposure due to infection or implant failure) in periods from 9 to 18 months after undergoing spinal osteosynthesis. Surgical implant removal occurred in 80% of the patients (4/5). Complete remission was not observed in the patient with residual implants. The association of pins/screws and PMMA is a versatile osteosynthesis technique and is applicable in all spinal regions. However, delayed complications can occur, which could require additional surgical procedures. Despite the small number of cases included in this study, one can infer that complications related to the use of bone cement in spinal surgery can occur in the long term and should be highlighted during the implant choosing process for vertebral osteosynthesis in small animals.

O trauma vertebromedular é uma afecção comum na rotina clínica de pequenos animais e resulta, muitas vezes, em fraturas e luxações vertebrais (FLV) associadas à laceração, concussão, compressão ou isquemia da medula espinhal. Essas lesões apresentam sinais clínicos que variam de dor moderada a grave, acompanhada por perda parcial ou total das funções motoras, sensoriais e viscerais, podendo resultar no óbito ou na indicação de eutanásia. O objetivo deste trabalho é descrever cinco casos de complicações inerentes o uso de cimento ósseo para estabilização vertebral em quatro cães e um gato. Os pacientes possuíam idades variando entre cinco meses a quatro anos, peso entre 1,4 e 12,2kg e foram atendidos no Serviço de Ortopedia e Traumatologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, com histórico de reações cutâneas ao polimetilmetacrilato (PMMA), como tratos drenantes ou exposição do cimento decorrente de infecção ou soltura precoce do implante, em períodos que variaram de nove à 18 meses após serem submetidos a osteossíntese da coluna vertebral. Foi realizada a remoção cirúrgica desses implantes em quatro pacientes e mantida a estabilização prévia em um caso. Houve resolução total do quadro de infecção nos pacientes em que se removeu o PMMA associada ao tratamento clínico, e remissão parcial no paciente em que o implante não pode ser removido. A utilização do cimento ósseo associado a parafusos ou pinos é uma técnica versátil e aplicável em todas as regiões da coluna vertebral, no entanto complicações tardias são possíveis, sendo necessário muitas vezes procedimentos cirúrgicos adicionais para a resolução do problema. Apesar da pequena quantidade de casos relatados, foi possível observar que complicações relacionadas ao uso do cimento ósseo na coluna vertebral podem ocorrer no médio ao longo prazo [...].

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Vertebral and spinal cord trauma are common conditions in small animal practice and often result in vertebral fractures/luxation (VFL) with concomitant spinal cord laceration, concussion, compression, or ischemia. These lesions have several clinical presentations that may vary from moderate to severe pain and partial to total loss of motor, sensory, and visceral functions, which may result in death or euthanasia. Our purpose is to describe five cases (four dogs and one cat) of complications secondary to the use of bone cement for vertebral stabilization. The patients, between five months and four years of age and weighing between 1.4 and 12.2 kg, were referred to the Small Animal Orthopedics and Traumatology Service of the Veterinary Hospital of the College of Veterinary Medicine and Animal Science of the University of São Paulo. They had a history of post-operatory polymethyl methacrylate (PMMA) reactions (such as drainage or cement exposure due to infection or implant failure) in periods from 9 to 18 months after undergoing spinal osteosynthesis. Surgical implant removal occurred in 80% of the patients (4/5). Complete remission was not observed in the patient with residual implants. The association of pins/screws and PMMA is a versatile osteosynthesis technique and is applicable in all spinal regions. However, delayed complications can occur, which could require additional s

O trauma vertebromedular é uma afecção comum na rotina clínica de pequenos animais e resulta, muitas vezes, em fraturas e luxações vertebrais (FLV) associadas à laceração, concussão, compressão ou isquemia da medula espinhal. Essas lesões apresentam sinais clínicos que variam de dor moderada a grave, acompanhada por perda parcial ou total das funções motoras, sensoriais e viscerais, podendo resultar no óbito ou na indicação de eutanásia. O objetivo deste trabalho é descrever cinco casos de complicações inerentes o uso de cimento ósseo para estabilização vertebral em quatro cães e um gato. Os pacientes possuíam idades variando entre cinco meses a quatro anos, peso entre 1,4 e 12,2kg e foram atendidos no Serviço de Ortopedia e Traumatologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, com histórico de reações cutâneas ao polimetilmetacrilato (PMMA), como tratos drenantes ou exposição do cimento decorrente de infecção ou soltura precoce do implante, em períodos que variaram de nove à 18 meses após serem submetidos a osteossíntese da coluna vertebral. Foi realizada a remoção cirúrgica desses implantes em quatro pacientes e mantida a estabilização prévia em um caso. Houve resolução total do quadro de infecção nos pacientes em que se removeu o PMMA associada ao tratamento cl

RESUMEN

Vertebral and spinal cord trauma are common conditions in small animal practice and often result in vertebral fractures/luxation (VFL) with concomitant spinal cord laceration, concussion, compression, or ischemia. These lesions have several clinical presentations that may vary from moderate to severe pain and partial to total loss of motor, sensory, and visceral functions, which may result in death or euthanasia. Our purpose is to describe five cases (four dogs and one cat) of complications secondary to the use of bone cement for vertebral stabilization. The patients, between five months and four years of age and weighing between 1.4 and 12.2 kg, were referred to the Small Animal Orthopedics and Traumatology Service of the Veterinary Hospital of the College of Veterinary Medicine and Animal Science of the University of São Paulo. They had a history of post-operatory polymethyl methacrylate (PMMA) reactions (such as drainage or cement exposure due to infection or implant failure) in periods from 9 to 18 months after undergoing spinal osteosynthesis. Surgical implant removal occurred in 80% of the patients (4/5). Complete remission was not observed in the patient with residual implants. The association of pins/screws and PMMA is a versatile osteosynthesis technique and is applicable in all spinal regions. However, delayed complications can occur, which could require additional surgical procedures. Despite the small number of cases included in this study, one can infer that complications related to the use of bone cement in spinal surgery can occur in the long term and should be highlighted during the implant choosing process for vertebral osteosynthesis in small animals.(AU)

O trauma vertebromedular é uma afecção comum na rotina clínica de pequenos animais e resulta, muitas vezes, em fraturas e luxações vertebrais (FLV) associadas à laceração, concussão, compressão ou isquemia da medula espinhal. Essas lesões apresentam sinais clínicos que variam de dor moderada a grave, acompanhada por perda parcial ou total das funções motoras, sensoriais e viscerais, podendo resultar no óbito ou na indicação de eutanásia. O objetivo deste trabalho é descrever cinco casos de complicações inerentes o uso de cimento ósseo para estabilização vertebral em quatro cães e um gato. Os pacientes possuíam idades variando entre cinco meses a quatro anos, peso entre 1,4 e 12,2kg e foram atendidos no Serviço de Ortopedia e Traumatologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, com histórico de reações cutâneas ao polimetilmetacrilato (PMMA), como tratos drenantes ou exposição do cimento decorrente de infecção ou soltura precoce do implante, em períodos que variaram de nove à 18 meses após serem submetidos a osteossíntese da coluna vertebral. Foi realizada a remoção cirúrgica desses implantes em quatro pacientes e mantida a estabilização prévia em um caso. Houve resolução total do quadro de infecção nos pacientes em que se removeu o PMMA associada ao tratamento clínico, e remissão parcial no paciente em que o implante não pode ser removido. A utilização do cimento ósseo associado a parafusos ou pinos é uma técnica versátil e aplicável em todas as regiões da coluna vertebral, no entanto complicações tardias são possíveis, sendo necessário muitas vezes procedimentos cirúrgicos adicionais para a resolução do problema. Apesar da pequena quantidade de casos relatados, foi possível observar que complicações relacionadas ao uso do cimento ósseo na coluna vertebral podem ocorrer no médio ao longo prazo [...].(AU)

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Vertebral and spinal cord trauma are common conditions in small animal practice and often result in vertebral fractures/luxation (VFL) with concomitant spinal cord laceration, concussion, compression, or ischemia. These lesions have several clinical presentations that may vary from moderate to severe pain and partial to total loss of motor, sensory, and visceral functions, which may result in death or euthanasia. Our purpose is to describe five cases (four dogs and one cat) of complications secondary to the use of bone cement for vertebral stabilization. The patients, between five months and four years of age and weighing between 1.4 and 12.2 kg, were referred to the Small Animal Orthopedics and Traumatology Service of the Veterinary Hospital of the College of Veterinary Medicine and Animal Science of the University of São Paulo. They had a history of post-operatory polymethyl methacrylate (PMMA) reactions (such as drainage or cement exposure due to infection or implant failure) in periods from 9 to 18 months after undergoing spinal osteosynthesis. Surgical implant removal occurred in 80% of the patients (4/5). Complete remission was not observed in the patient with residual implants. The association of pins/screws and PMMA is a versatile osteosynthesis technique and is applicable in all spinal regions. However, delayed complications can occur, which could require additional s

O trauma vertebromedular é uma afecção comum na rotina clínica de pequenos animais e resulta, muitas vezes, em fraturas e luxações vertebrais (FLV) associadas à laceração, concussão, compressão ou isquemia da medula espinhal. Essas lesões apresentam sinais clínicos que variam de dor moderada a grave, acompanhada por perda parcial ou total das funções motoras, sensoriais e viscerais, podendo resultar no óbito ou na indicação de eutanásia. O objetivo deste trabalho é descrever cinco casos de complicações inerentes o uso de cimento ósseo para estabilização vertebral em quatro cães e um gato. Os pacientes possuíam idades variando entre cinco meses a quatro anos, peso entre 1,4 e 12,2kg e foram atendidos no Serviço de Ortopedia e Traumatologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, com histórico de reações cutâneas ao polimetilmetacrilato (PMMA), como tratos drenantes ou exposição do cimento decorrente de infecção ou soltura precoce do implante, em períodos que variaram de nove à 18 meses após serem submetidos a osteossíntese da coluna vertebral. Foi realizada a remoção cirúrgica desses implantes em quatro pacientes e mantida a estabilização prévia em um caso. Houve resolução total do quadro de infecção nos pacientes em que se removeu o PMMA associada ao tratamento cl

RESUMEN

Vertebral and spinal cord trauma are common conditions in small animal practice and often result in vertebral fractures/luxation (VFL) with concomitant spinal cord laceration, concussion, compression, or ischemia. These lesions have several clinical presentations that may vary from moderate to severe pain and partial to total loss of motor, sensory, and visceral functions, which may result in death or euthanasia. Our purpose is to describe five cases (four dogs and one cat) of complications secondary to the use of bone cement for vertebral stabilization. The patients, between five months and four years of age and weighing between 1.4 and 12.2 kg, were referred to the Small Animal Orthopedics and Traumatology Service of the Veterinary Hospital of the College of Veterinary Medicine and Animal Science of the University of São Paulo. They had a history of post-operatory polymethyl methacrylate (PMMA) reactions (such as drainage or cement exposure due to infection or implant failure) in periods from 9 to 18 months after undergoing spinal osteosynthesis. Surgical implant removal occurred in 80% of the patients (4/5). Complete remission was not observed in the patient with residual implants. The association of pins/screws and PMMA is a versatile osteosynthesis technique and is applicable in all spinal regions. However, delayed complications can occur, which could require additional s

O trauma vertebromedular é uma afecção comum na rotina clínica de pequenos animais e resulta, muitas vezes, em fraturas e luxações vertebrais (FLV) associadas à laceração, concussão, compressão ou isquemia da medula espinhal. Essas lesões apresentam sinais clínicos que variam de dor moderada a grave, acompanhada por perda parcial ou total das funções motoras, sensoriais e viscerais, podendo resultar no óbito ou na indicação de eutanásia. O objetivo deste trabalho é descrever cinco casos de complicações inerentes o uso de cimento ósseo para estabilização vertebral em quatro cães e um gato. Os pacientes possuíam idades variando entre cinco meses a quatro anos, peso entre 1,4 e 12,2kg e foram atendidos no Serviço de Ortopedia e Traumatologia do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, com histórico de reações cutâneas ao polimetilmetacrilato (PMMA), como tratos drenantes ou exposição do cimento decorrente de infecção ou soltura precoce do implante, em períodos que variaram de nove à 18 meses após serem submetidos a osteossíntese da coluna vertebral. Foi realizada a remoção cirúrgica desses implantes em quatro pacientes e mantida a estabilização prévia em um caso. Houve resolução total do quadro de infecção nos pacientes em que se removeu o PMMA associada ao tratamento cl

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A incorporação de íons na estrutura da hidroxiapatita (HA) pode afetar sua estrutura, cristalinidade, solubilidade e citotoxicidade. Dentre os íons presentes na composição da apatita óssea, o magnésio (Mg2+), estrôncio (Sr2+) e zinco (Zn2+) são reconhecidos por promover a angiogênese e osteogênese. Portanto, as HAs substituídas podem apresentar melhor bioatividade, por fornecer íons com potencial de estimular a neoformação óssea nos locais enxertados. Nesse contexto, este estudo descreve a síntese, caracterização e comparação de uma série de nano-hidroxiapatitas (nHAs) substituídas e co-substituídas por Sr2+, Mg2+ ou Zn2+. Em seguida, foi desenvolvido um cimento ósseo à base das HAs com melhores resultados de citotoxicidade, associado ao DCPA, gelatina e quitosana. As nHAs foram caracterizadas físico-quimicamente usando diferentes técnicas. O método de co-precipitação foi eficaz para sintetizar HAs de dimensões nanométricas. Comparado a nHA pura, os difratogramas, espectros de FTIR e parâmetros de rede das nHAs substituídas e co-substituídas exibiram alterações, indicando que a incorporação de cátions resultou em distorções da rede da HA. Os testes de MTT demonstraram que as nHAs sintetizadas não foram citotóxicas, após contato direto com culturas de fibroblastos (L929) e pré-osteoblastos (MC3T3). Os resultados obtidos sugerem que as nHAs co-substituídas por Mg2+/Sr2+ e Zn2+/Sr2+ parecem induzir maior proliferação de células fibroblásticas e osteoblásticas, quando comparado a HA pura e substituída. Os cimentos ósseos desenvolvidos apresentaram capacidade de auto-endurecimento e resistência à lavagem. Além de possuírem alta molhabilidade e um perfil de liberação de íons Ca2+, Sr2+, Mg2+ e Zn2+, que está dentro das doses indicadas para estimular a proliferação de osteoblastos. Os cimentos exibiram excelente biocompatibilidade in vitro em culturas de células fibroblásticas, endoteliais e osteosblásticas. Os cimentos contendo nHAs co-substituídas por Mg2+/Sr2+ exibiram os melhores resultados de viabilidade celular. Após 24 horas de contato indireto com cultura de células fibroblásticas L929, o crescimento celular do grupo C2 foi maior que de todos os grupos em estudo (P < 0,01). Em cultura de células endoteliais EA.hy926, o percentual de células viáveis do grupo C3 foi significativamente maior que de todos os outros grupos, após 24 horas (p < 0,001). A citotoxicidade indireta em cultura de células pré-osteoblásticas MC3T3 revelou que após 48 horas, o grupo C3 apresentou maior viabilidade celular que todos os grupos em estudo (p < 0,01). O teste de formação de tubo sugere que todos os cimentos desenvolvidos possuem potencial angiogênico, sendo que os cimentos contendo nHAs co-substituídas por Zn2+/Sr2+ exibiram resultados significativamente superiores (p < 0,001). Apesar de ser necessário um maior número de testes de biocompatibilidade; a incorporação de íons na rede cristalina das nHAs, que são reconhecidos por afetar a angiogênese e a osteogênese, parece ter resultado no desenvolvimento de cimentos ósseos com potencial para promover a regeneração óssea.

The incorporation of ions into the HA lattice can affect its structure, crystallinity, solubility and cytotoxicity. From the ions present in the composition of bone apatite, Mg2+, Sr2+ and Zn2+ are recognized for promoting angiogenesis and osteogenesis. The substituted HAs can be present better bioactivity for supplying ions with potential to stimulate bone neoformation in grafted sites. This study described the synthesis, characterization and comparison of a range of substituted and co-substituted nHAs contained Sr2+, Mg2+ or Zn2+. Then, it developed bone cement based on HAs with better cytotoxicity results, associated with DCPA, gelatin and chitosan. The nHAs were physicochemically characterized using different techniques. The co-precipitation method was effective for synthesizing HAs with nanometric dimensions. Compared to pure nHA, the diffractograms, FTIR spectra and lattice parameters of the substituted and co-substituted nHAs showed changes, indicating that the incorporation of cations resulted in distortions of the HA lattice. MTT tests demonstrated that the all synthesized nHAs were not cytotoxic after direct contact with fibroblasts (L929) and pre-osteoblasts (MC3T3) cultures. MTT results suggest that Mg2+/Sr2+ and Zn2+/Sr2+ co-substituted nHAs seem to induce more proliferation of fibroblastic and osteoblastic than pure and Mg2+, Sr2+ and Zn2+ substituted nHAs. Bone cements developed showed self-hardening and washout resistance. Also, they Exhibited high wettability and ion release profile with non-toxic concentrations of Ca2+, Sr2+, Mg2+ and Zn2+, range within indicated doses to stimulate the proliferation of osteoblasts. The cement exhibited excellent in vitro cytocompatibility in fibroblastic, endothelial and osteoblastic cell cultures. Cement containing Mg2+/Sr2+ co-substituted nHAs showed better results of the cell viability. After 24 hours of indirect contact with L929 fibroblast culture, the cell growth in the C2 group was highest than all study groups (P <0.01). In EA.hy926 endothelial culture, the cell viability of the C3 group was significantly highest than all other groups after 24 hours (p <0.001). The indirect cytotoxicity in MC3T3 pre-osteoblastic culture revealed that after 48 hours, the C3 group showed the greatest cell viability than all the study groups (p <0.01). The tube formation assay suggests that all cement have angiogenic potential, being that the cements containing Zn2+ / Sr2+ co-substituted nHAs exhibited significantly better results (p < 0,001). Despite being necessary to perform a more significant number of biocompatibility tests, the incorporation of ions into the nHA lattice, which are recognized for affects angiogenesis and osteogenesis, may have resulted in the development of bone cements with the potential to promoting bone regeneration.

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Introducción El síndrome de implantación de cemento óseo (SICO) es una complicacion intraoperatoria frecuente y potencialmente devastadora en pacientes sometidos a artroplastia de cadera cementada. Objetivo Describir la frecuencia del SICO en pacientes llevados a artroplastia total o parcial de cadera, mayores de 50 años, en el Hospital de San José de Bogotá, entre el 1 de enero del 2012 al 31 de Enero del 2018. Metodología Estudio serie de casos. Se revisaron los registros médicos de pacientes adultos mayores de 50 años con indicación de Artroplastia o Hemiatroplastia. Se analizaron las variables perioperatorias a través del registro de Anestesia. Mediante la clasificación de Donaldson se determinó el grado de SICO. Se emplearon estadísticas descriptivas y análisis de correspondencias múltiples para explorar la relación entre las variables. Resultados Incluimos 49 pacientes con una media de edad de 78 años (DE +/- 9.9), 39 eran mujeres (79.6%) y 37 (75.5%) tuvieron una clasificacion ASA II. Documentamos la presencia de SICO en 8 pacientes (16.3%): de los cuales 5 correspondian a Grado 1, 2 Grado 2 y 1 a Grado 3 con requerimiento de UCI. 7 eran mujeres; todos tenían antecedente de hipertension arterial, 2 diabetes mellitus, 2 EPOC y 1 osteoporosis. Ninguno reportó ingesta de Warfarina. Conclusiones SICO es un fenómeno frecuente en la artroplastia y hemiartroplastia cementada, siendo mayor en el sexo femenino, documentandose la presencia de predictores de severidad clasificacion ASA II ­III y el antecedente de EPOC en nuestro hospital.

Background The bone cement implantation syndrome (BCIS) is a frequent and potentially devastating intraoperative complication in patients undergoing cemented hip arthroplasty. The objective of study is to describe the frequency of BCIS in patients undergoing total or partial hip arthroplasty. Methods Case series study. We reviewed the medical records of adult patients over 50 years of age with an indication for Arthroplasty or Hemiatroplasty. The perioperative variables were analyzed through the Anesthesia registry. The degree of SICO was determined by Donaldson classification. Descriptive statistics and multiple correspondence analysis were used to explore the relationship between the variables. Results We included 49 patients with an average age of 78 years (SD +/- 9.9), 39 were women (79.6%) and 37 (75.5%) had an ASA II classification. We documented the presence of SICO in 8 patients (16.3%): of which 5 corresponded to Grade 1, 2 Grade 2 and 1 to Grade 3 with ICU requirement. 7 were women; all were hypertensive, 2 diabetes mellitus, 2 COPD and 1 osteoporosis. None reported Warfarin ingestion. Discussion BCIS is a frequent phenomenon in the arthroplasty and cemented hemiarthroplasty, being higher in the female sex, documenting the presence of predictors of severity ASA II -III classification and the history of COPD in our hospital.

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Objective The purpose of the present study was to evaluate retrospectively the clinical and radiographic results of total hip arthroplasty (THA) performed with the Exeter technique and using the Exeter prosthesis. Methods Between March 2000 and December 2006, 504 THAs were performed in 477 patients, with several etiological diagnoses. A total of 260 surgeries were performed on the right side, 244 on the left side, and 27 were performed bilaterally. The mean age of the patients was 58.9 (17.7-86.8) years old, with a median of 69.0 years old. The preoperative planning was performed with appropriate templates. All of the surgeries were performed through the posterolateral approach with the patient placed on lateral decubitus. The clinical evaluation was performed according to the Harris hip score (HHS). In the radiographic evaluation, the bone cement interface in the three zones of DeLee and Charnley on the acetabular side and in the seven zones of Gruen on the femoral side were studied. Subsidence of the femoral component, presence of diaphyseal hyperthrophy, and heterotopic ossification were also observed. Results The mean follow-up of 441 surgeries (87.5%) was of 7.2 (1.0-16.6) years, with a median of 7.1 years. The incidence of complications was: dislocation, 3.2%; infection, 2.2%; peripheral nerve disorders 2.0%; thromboembolism 2.7%, acetabular cup loosing 2.0%; diaphyseal hypertrophy, 1.26%; distal migration of the femoral component between 2,0 mm and 2.9 mm, 0.5%; 1 case of aseptic loosing of the femoral component and 9 (1.8%) of the acetabular component. The mean HHS was mean 92.3 (50-100) points. Conclusion Cemented THA, with the methodology applied, proved to be an effective treatment for this group of patients. The results were satisfactory with acceptable complication rates.

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Abstract Objective The purpose of the present study was to evaluate retrospectively the clinical and radiographic results of total hip arthroplasty (THA) performed with the Exeter technique and using the Exeter prosthesis. Methods Between March 2000 and December 2006, 504 THAs were performed in 477 patients, with several etiological diagnoses. A total of 260 surgeries were performed on the right side, 244 on the left side, and 27 were performed bilaterally. The mean age of the patients was 58.9 (17.7-86.8) years old, with a median of 69.0 years old. The preoperative planning was performed with appropriate templates. All of the surgeries were performed through the posterolateral approach with the patient placed on lateral decubitus. The clinical evaluation was performed according to the Harris hip score (HHS). In the radiographic evaluation, the bone cement interface in the three zones of DeLee and Charnley on the acetabular side and in the seven zones of Gruen on the femoral side were studied. Subsidence of the femoral component, presence of diaphyseal hyperthrophy, and heterotopic ossification were also observed. Results The mean follow-up of 441 surgeries (87.5%) was of 7.2 (1.0-16.6) years, with a median of 7.1 years. The incidence of complications was: dislocation, 3.2%; infection, 2.2%; peripheral nerve disorders 2.0%; thromboembolism 2.7%, acetabular cup loosing 2.0%; diaphyseal hypertrophy, 1.26%; distal migration of the femoral component between 2,0 mm and 2.9 mm, 0.5%; 1 case of aseptic loosing of the femoral component and 9 (1.8%) of the acetabular component. The mean HHS was mean 92.3 (50-100) points. Conclusion Cemented THA, with themethodology applied, proved to be an effective treatment for this group of patients. The results were satisfactory with acceptable complication rates.

Resumo Objetivo Avaliar os resultados da artroplastia total do quadril (ATQ) cimentada, coma utilização da técnica e prótese da escola Exeter. Metódo Entre março de 2000 e dezembro de 2006, foram realizadas 504 ATQs em 477 pacientes, com diversos diagnósticos etiológicos, 260 à direita e 244 à esquerda, 27 bilaterais,. A idade média foi de 58,9 (17,7-86,8) anos, com mediana de 69,0 anos. O planejamento radiográfico foi feito utilizando-se gabaritos apropriados. O acesso cirúrgico foi o posterolateral com o paciente em decúbito lateral. Para a avaliação clínica, foi utilizado o escore do quadril de Harris (EQH). Na avaliação radiográfica, foi estudada a interface osso-cimento acetabular, nas três zonas de DeLee e Charnley e nas sete zonas de Gruen do lado femoral, a presença de migração distal do componente femoral, hipertrofia diafisária, e ossificação heterotópica. Resultados O seguimento médio de 441 cirurgias (87,5%) foi de 7,2 (1,0-16,6) anos, com mediana de 7,1 anos. A incidência de complicações foi: luxação, 3,2%; infecção ,2,2%; tromboembolismo, 2,1%; disfunção de nervos periféricos 1,1%; hipertrofia diafisária, 1,5%; soltura do componente acetabular, 1,8%; migração distal do componente femoral entre 2,0mm e 2,9 mm, 0,45%; 1 caso de soltura asséptica do componente femoral; e 1 caso de fratura da haste femoral. A pontuação média com o EQH foi de 92 pontos. Conclusão A ATQ cimentada, com a metodologia utilizada, constituiu-se em uma opção eficaz para o tratamento deste grupo de pacientes, comresultados satisfatórios, com este tempo de seguimento.

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