Accelerated rehabilitation versus conventional rehabilitation in total hip arthroplasty (ARTHA): a randomized double blinded clinical trial.

OBJECTIVES: compare an accelerated physiotherapeutic protocol to a conventional physiotherapeutic protocol in total hip arthroplasty patients. METHODS: a randomized double blinded clinical trial performed from August 2013 to November 2014. Forty-eight patients diagnosed with hip osteoarthritis submitted to a total hip arthroplasty surgery. An accelerated rehabilitation physiotherapy applied three times a day and start gait training on the first day or standard physiotherapy applied once a day and start gait training on the second or third day of hospitalization. The Merle dAubigné and Postel score (mobility, pain and gait), muscle strength force, range of motion, in hospital stay and time to start of gait training, were the outcomes. RESULTS: the mean age was 64.46 years (10.37 years standard deviation). No differences were observed in age in different genders, and the two randomization groups were homogeneous. In hospital stay was lower in the intervention group compared to the control group, 3 (3-4) days [median (interquartile range)] versus 4 (4-5) days. Time to the start of gait training was early in the intervention group compared to the control group, 1 (1-1) days versus 2 (2-2) days. Higher muscle strength values were observed in the postoperative results in the intervention group compared to the control group for internal rotation, external rotation and abduction. CONCLUSIONS: an accelerated physiotherapeutic protocol should be encouraged, because it shows favourable results in gait, muscle strength and length of hospital stay, even upon hospital discharge.

Accelerated rehabilitation versus conventional rehabilitation in total hip arthroplasty (ARTHA): a randomized double blinded clinical trial / Reabilitação acelerada versus reabilitação convencional na artroplastia total do quadril (ARTHA): um ensaio clínico randomizado, duplo cego

ABSTRACT Objectives: compare an accelerated physiotherapeutic protocol to a conventional physiotherapeutic protocol in total hip arthroplasty patients. Methods: a randomized double blinded clinical trial performed from August 2013 to November 2014. Forty-eight patients diagnosed with hip osteoarthritis submitted to a total hip arthroplasty surgery. An accelerated rehabilitation physiotherapy applied three times a day and start gait training on the first day or standard physiotherapy applied once a day and start gait training on the second or third day of hospitalization. The Merle dAubigné and Postel score (mobility, pain and gait), muscle strength force, range of motion, in hospital stay and time to start of gait training, were the outcomes. Results: the mean age was 64.46 years (10.37 years standard deviation). No differences were observed in age in different genders, and the two randomization groups were homogeneous. In hospital stay was lower in the intervention group compared to the control group, 3 (3-4) days [median (interquartile range)] versus 4 (4-5) days. Time to the start of gait training was early in the intervention group compared to the control group, 1 (1-1) days versus 2 (2-2) days. Higher muscle strength values were observed in the postoperative results in the intervention group compared to the control group for internal rotation, external rotation and abduction. Conclusions: an accelerated physiotherapeutic protocol should be encouraged, because it shows favourable results in gait, muscle strength and length of hospital stay, even upon hospital discharge.

RESUMO Objetivos: comparar um protocolo fisioterapêutico acelerado com um protocolo fisioterapêutico convencional em pacientes submetidos a artroplastia total do quadril. Métodos: ensaio clínico randomizado, duplo-cego, realizado de agosto/2013 a novembro/2014. Quarenta e oito pacientes diagnosticados com coxartrose submetidos a cirurgia de artroplastia total do quadril. Fisioterapia de reabilitação acelerada aplicada três vezes ao dia com início de marcha no primeiro dia ou fisioterapia convencional aplicada uma vez ao dia e início de marcha no segundo ou terceiro dia de hospitalização. Os escores de Merle dAubigné e Postel (mobilidade, dor e marcha), força muscular, amplitude de movimento, internação hospitalar e tempo para o início de marcha foram os desfechos. Resultados: a idade média foi 64,46 anos (desvio padrão 10,37 anos). Não foram observadas diferenças na idade nos diferentes sexos, e os grupos de randomização foram homogêneos. O tempo de internação hospitalar foi menor no grupo intervenção em comparação ao grupo controle, 3 (3-4) dias [mediana (intervalo interquartil)] versus 4 (4-5) dias. O tempo para início da marcha foi precoce no grupo de intervenção em comparação ao grupo controle, 1 (1-1) dias versus 2 (2-2) dias. Maiores valores de força muscular foram observados nos resultados pós-operatórios no grupo intervenção em comparação ao grupo controle para rotação interna, rotação externa e abdução. Conclusões: um protocolo fisioterapêutico acelerado deve ser incentivado, pois apresenta resultados favoráveis na marcha, força muscular e tempo de internação, mesmo após a alta hospitalar.

Prevalence of radiographic markers of femoroacetabular impingement in asymptomatic adults.

OBJECTIVE: to determine the prevalence of radiographic signs of femoroacetabular impingement (FAI) in asymptomatic adults and correlate them with data from physical examinations. METHODS: We conducted a cross-sectional study with 82 asymptomatic volunteers, 164 hips, between 40 and 60 years of age, selected by convenience. They were submitted to anamnesis and clinical examination of the hip, anteroposterior (AP) pelvis radiographs with three incidences, Dunn 45° and Lequesne false profile of each hip, to measure the variables. We measured the alpha angle, anterior offset of the femoral neck, cervical diaphyseal angle, CE angle of Wiberg, acetabular index, Sharp angle, and the crossing, ischial spine and posterior wall signs. RESULTS: our sample consisted of 66% women, mean age of 50.4 years. The average alpha angle was 45.10°, SD=8.6. One quarter of the hips showed alpha angle greater than or equal to 50°; among men the prevalence was 34%, and among women, 11%. We found indicative radiographic signs of femoroacetabular impingement in 42.6% of hips, whether femoral or acetabular, and the increased alpha angle was related to the decrease in hip internal rotation (p<0.001). CONCLUSION: the radiographic findings of femoroacetabular impingement in asymptomatic patients were frequent in the studied sample. The increase in alpha angle was associated with decreased internal rotation.

Prevalence of radiographic markers of femoroacetabular impingement in asymptomatic adults / Prevalência dos achados radiográficos de impacto femoroacetabular em adultos assintomáticos

OBJECTIVE: to determine the prevalence of radiographic signs of femoroacetabular impingement (FAI) in asymptomatic adults and correlate them with data from physical examinations. METHODS: We conducted a cross-sectional study with 82 asymptomatic volunteers, 164 hips, between 40 and 60 years of age, selected by convenience. They were submitted to anamnesis and clinical examination of the hip, anteroposterior (AP) pelvis radiographs with three incidences, Dunn 45° and Lequesne false profile of each hip, to measure the variables. We measured the alpha angle, anterior offset of the femoral neck, cervical diaphyseal angle, CE angle of Wiberg, acetabular index, Sharp angle, and the crossing, ischial spine and posterior wall signs. RESULTS: our sample consisted of 66% women, mean age of 50.4 years. The average alpha angle was 45.10°, SD=8.6. One quarter of the hips showed alpha angle greater than or equal to 50°; among men the prevalence was 34%, and among women, 11%. We found indicative radiographic signs of femoroacetabular impingement in 42.6% of hips, whether femoral or acetabular, and the increased alpha angle was related to the decrease in hip internal rotation (p<0.001). CONCLUSION: the radiographic findings of femoroacetabular impingement in asymptomatic patients were frequent in the studied sample. The increase in alpha angle was associated with decreased internal rotation. .

OBJETIVO: determinar a prevalência dos sinais radiográficos de impacto femoroacetabular (IFA) em adultos assintomáticos e correlacionar com dados do exame físico. MÉTODOS: estudo transversal, com 82 voluntários, 164 quadris, selecionados por conveniência, assintomáticos, entre 40 e 60 anos de idade. Esses foram submetidos à anamnese e exame clínico do quadril, exame radiográfico com três incidências, antero-posterior (AP) de bacia, Dunn a 45° e falso perfil de Lequesne de cada quadril, para mensuração das variáveis. Aferimos o ângulo alfa, offset anterior do colo femoral, ângulo cérvico diafisário, ângulo CE de Wiberg, índice acetabular, ângulo de Sharp, além dos sinais do cruzamento, da espinha isquiática e da parede posterior. RESULTADOS: nossa amostra foi formada por 66% de mulheres, com média de idade de 50,4 anos. O ângulo alfa médio foi de 45.10º, DP = 8.6. 25% dos quadris apresentaram ângulo alfa maior ou igual a 50°; entre os homens a prevalência foi 34% e entre as mulheres 11%. Encontramos sinais radiográficos indicativos de impacto femoroacetabular em 42,6% dos quadris, sejam eles femorais ou acetabulares, e o aumento do ângulo alfa esteve relacionado com o decréscimo na rotação interna do quadril (p < 0,001). CONCLUSÃO: Os achados radiográficos de impacto femoroacetabular em pacientes assintomáticos foram frequentes na amostra estudada. O aumento do ângulo alfa esteve relacionado com o decréscimo da rotação interna. .

Femoral stem-bone interface analysis of logical uncemented stem / Análise numérica do comportamento biomecânico da haste femoral não-cimentada Logical

This paper evaluates the mechanical behavior of an uncemented hip stem using finite element analysis. The analysis is focused on the stem-bone interaction which is assessed by simulation of distinct conditions encountered daily on orthopedic practice of hip implants. Logical uncemented femoral stem was used in this work. Three distinct conditions have been modeled: a) exposed neck with fully embedded fins, b) partially exposed anti-rotational fins and c) fully exposed fins, representing real femoral hip conditions. Anthropometric variations and different angulations for the stem neck were investigated for typical body weight of populations submitted to implants. The ratio of mobilized stress to yield stress is shown to be lower than 55% indicating a safety factor against stem failure. Although small displacements are observed in all conditions, the displacement increases with the increase of both the length of exposed fins and the magnitude of applied forces. Even for the extreme condition of fully exposed fins, the prostheses will support the working loads, and the risk of bone fracture still has a safety factor. Stresses and displacements change considerably with neck angulations suggesting that anthropometric variations should be considered in the future to optimize prostheses performance. Numerical analysis of the used uncemented femoral stem demonstrated that small stresses and strains are generated under working load conditions indicating that a proper factor of safety is obtained for the static conditions tested in the present study.

A presente pesquisa avalia o comportamento mecânico da haste femoral não-cimentada Logical através de elementos finitos. Foram analisadas diferentes condições de contorno encontradas na prática ortopédica: a) apenas o colo exposto; b) com as aletas anti-rotatórias parcialmente expostas; e c) com as aletas totalmente expostas. Variações antropométricas foram consideradas pelas diferentes angulações de colo propostas e através de diferentes cargas aplicadas. A haste apresentou um bom coeficiente de segurança. Embora pequenos deslocamentos sejam observados em todas as condições, existe um maior deslocamento com o aumento da exposição das aletas da prótese. Mesmo para a condição extrema com as aletas totalmente expostas, a prótese suporta as cargas de trabalho e ainda há um bom fator de segurança. Tensões e deslocamentos se modificam consideravelmente com as diferentes angulações propostas para o colo, sugerindo que as variações antropométricas devam ser consideradas no futuro para otimizar o desempenho da prótese.

BOVINE LYOPHILIZED GRAFT (BLG): HISTOLOGICAL ANALYSIS ON BEHAVIOR IN HUMANS AFTER 49 MONTHS.

OBJECTIVE: To analyze the histological behavior of bovine lyophilized grafts (BLG) produced according to a protocol developed by the first author, in humans over a 49-month period by measuring the graft/bone neoformation ratio in relation to the total mineralized area. METHODS: This was a case series involving 12 patients: eight females (66%) and four males (34%), totaling 13 biopsies. BLG was used, and surgical reintervention was subsequently required during the period 2000 to 2011. The slides produced were stained with hematoxylin-eosin (HE), were analyzed by a pathologist and were digitized for the proposed evaluation. RESULTS: The mean age was 57 years and the mean follow-up was 49 months (range: 6-115). The average proportion of BLG was 42% (range: 13-85) and neoformed bone, 58% (range: 15-87) in relation to the total area mineralized. CONCLUSIONS: This study demonstrated that the BLG used presented osteoconductive characteristics and biocompatibility. BLG is a therapeutic option that can be used in orthopedic surgery in which bone defects need to be filled.

Enxerto bovino liofilizado: comportamento histológico após seguimento de 49 meses em seres humanos / Bovine lyophilized graft (BLG): histological analysis on behavior in humans after 49 months

OBJETIVO: Analisar o comportamento histológico do ELB, produzido conforme protocolo desenvolvido pelo autor principal, em seres humanos no decorrer de 49 meses através da aferição da proporção enxerto/osso neoformado em relação ao total de área mineralizada. MÉTODOS: Série de casos com 12 pacientes, oito femininos (66%) e quatro masculinos (34%), totalizando 13 biópsias, nos quais utilizou-se ELB e que posteriormente houve necessidade de reintervenção cirúrgica, no período de 2000 a 2011. As lâminas produzidas, coradas com hematoxilina-eosina (HE), foram analisadas por patologista e digitalizadas para a avaliação proposta. RESULTADOS: A média etária foi de 57 anos e o tempo médio de seguimento de 49 meses (6-115). A proporção média de ELB foi de 42% (13-85) e de osso neoformado de 58% (15-87) em relação ao total de área mineralizada. CONCLUSÕES: O presente estudo demonstra que o ELB utilizado apresenta característica osteocondutora e biocompatibilidade. O ELB apresentado é opção terapêutica a ser utilizada em cirurgias ortopédicas que necessitem preenchimento de deficiências ósseas.

OBJECTIVE: To analyze the histological behavior of bovine lyophilized grafts (BLG) produced according to a protocol developed by the first author, in humans over a 49-month period by measuring the graft/bone neoformation ratio in relation to the total mineralized area. METHODS: This was a case series involving 12 patients: eight females (66%) and four males (34%), totaling 13 biopsies. BLG was used, and surgical reintervention was subsequently required during the period 2000 to 2011. The slides produced were stained with hematoxylin-eosin (HE), were analyzed by a pathologist and were digitized for the proposed evaluation. RESULTS: The mean age was 57 years and the mean follow-up was 49 months (range: 6-115). The average proportion of BLG was 42% range: 13-85) and neoformed bone, 58% (range: 15-87) in relation to the total area mineralized. CONCLUSIONS: This study demonstrated that the BLG used presented osteoconductive characteristics and biocompatibility. BLG is a therapeutic option that can be used in orthopedic surgery in which bone defects need to be filled.

PHYSICOCHEMICAL CHARACTERIZATION OF LYOPHILIZED BOVINE BONE GRAFTS.

UNLABELLED: To evaluate the physicochemical characteristics of lyophilized bovine grafts manufactured on a semi-industrial scale (Orthogen; Baumer S/A*) in accordance with a protocol previously developed by the authors. METHODS: The lyophilized bovine bone grafts were characterized by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffractometry (XRD), thermogravimetric (TG) analysis, differential exploratory scanning calorimetry (DSC) and Fourier-transform infrared (FT-IR) spectroscopy. RESULTS: Ca was the main component (60%) found in the samples, followed by P (28%) and O (5%). The mean (sd) pore size was 316 µm (146.7), ranging from 91.2 to 497.8 µm, and 333.5 µm (304.8), ranging from 87.2 to 963.9 µm, at 50x and 150x magnification, respectively. The hydroxyapatite peaks were at 26°C and 32°C, and mass losses were observed between 250°C and 640°C, corresponding to organic material and water. Two temperature transitions (45.67°C and 91.89°C) showed denaturation of type 1 collagen and dehydration of hydroxyapatite. CONCLUSION: The physicochemical assessment of lyophilized bovine bone grafts in accordance with the protocol developed at semi-industrial scale confirmed that this product presents excellent biocompatibility, with characteristics similar to natural bone.

Caracterização físico-química do enxerto de osso bovino liofilizado / Physicochemical characterization of lyophilized bovine bone grafts

OBJETIVO: Avaliar as características físico-químicas do enxerto bovino liofilizado manufaturado em escala semi-industrial (OrthoGen, Baumer S/A*) de acordo com protocolo previamente desenvolvido pelos autores. MÉTODOS: A caracterização do enxerto de osso bovino liofilizado foi feita por meio de microscopia eletrônica de varredura (MEV), energy dispersive spectroscopy (EDS), difratometria de raios-X, análise por termogravimetria, análise de calorimetria exploratória diferencial (DSC) e espectroscopia por infravermelho Fourier-transform (FT-IR). RESULTADOS: Ca foi o principal componente (60 por cento) encontrado nas amostras, seguido por P (28 por cento) e O (5 por cento). O tamanho médio (dp) dos poros foi 316µm (146,7), variando de 91,2 a 497,8µm, e 333,5µm (304,8), variando de 87,2 a 963,9µm com 50x e 150x magnificação, respectivamente. Picos de hidroxiapatita foram a 26ºC e 32ºC, e perda de massa foi observada entre 250ºC e 640ºC, correspondendo material orgânico e água. Duas transições de temperatura (45,67°C e 91,89°C) mostraram desnaturação de colágeno tipo I e desidratação da hidroxiapatita. CONCLUSÃO: A avaliação físico-química do enxerto de osso bovino liofilizado, de acordo com o protocolo desenvolvido em escala semi-industrial, confirma que este produto apresenta excelente biocompatibilidade, com características semelhantes ao osso in natura.

OBJECTIVE: To evaluate the physicochemical characteristics of lyophilized bovine grafts manufactured on a semi-industrial scale (Orthogen; Baumer S/A*) in accordance with a protocol previously developed by the authors. METHODS: The lyophilized bovine bone grafts were characterized by means of scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffractometry (XRD), thermogravimetric (TG) analysis, differential exploratory scanning calorimetry (DSC) and Fourier-transform infrared (FT-IR) spectroscopy. RESULTS: Ca was the main component (60 percent) found in the samples, followed by P (28 percent) and O (5 percent). The mean (sd) pore size was 316 µm (146.7), ranging from 91.2 to 497.8 µm, and 333.5 µm (304.8), ranging from 87.2 to 963.9 µm, at 50x and 150x magnification, respectively. The hydroxyapatite peaks were at 26°C and 32°C, and mass losses were observed between 250°C and 640°C, corresponding to organic material and water. Two temperature transitions (45.67°C and 91.89°C) showed denaturation of type 1 collagen and dehydration of hydroxyapatite. CONCLUSION: The physicochemical assessment of lyophilized bovine bone grafts in accordance with the protocol developed at semi-industrial scale confirmed that this product presents excellent biocompatibility, with characteristics similar to natural bone.

TOTAL HIP ARTHROPLASTY WITH BIOMEC PROSTHESIS: 20-YEAR FOLLOW-UP.

OBJECTIVE: To analyze the clinical and radiological outcomes from total hip arthroplasty using the Biomec prosthesis over a 20-year period (1988 to 2009). METHODS: The patients were evaluated clinically in accordance with the Merle d'Aubigné and Postel functional classification, and underwent anteroposterior (AP) radiography of the pelvis and the operated joint in lateral view. The variables evaluated were acetabular and femoral osteolysis, polyethylene wear, nail migration, follow-up and clinical outcomes. RESULTS: The mean follow-up was 10.6 years (range 4 to 21 years). The sample consisted of 84 patients (32 men and 52 women) and the mean preoperative age was 47 years. We found that 88% of the results from the clinical evaluation were good or excellent. In relation to the radiological findings, 92.5% of the results were good. The mean wear on the polyethylene was 1.4 mm. CONCLUSION: The use of the Biomec prosthesis in this cohort showed good clinical and radiographic results.

Artroplastia total de quadril com prótese Biomec: 20 anos de seguimento / Total hip arthroplasty with Biomec: 20-year follow-up

OBJETIVO: Avaliar o desfecho clínico e radiográfico da artroplastia total de quadril (ATQ) com prótese Biomec em um período de 20 anos (1988 a 2008). MÉTODOS: Os pacientes foram avaliados clinicamente segundo a classificação funcional de Merle d'Aubigné e Postel e submetidos à radiografia de bacia em anteroposterior (AP) e da articulação operada em perfil. As variáveis avaliadas foram osteólise acetabular e femoral, desgaste do polietileno, migração da haste, seguimento e desfecho clínico. RESULTADOS: O seguimento médio foi de 10,6 anos (4 a 20 anos); a amostra foi de 84 pacientes, sendo 32 do sexo masculino e 52, do feminino; a idade média no pré-operatório foi de 47 anos; obtivemos 88 por cento de resultados bons e muito bons na avaliação clínica. Com relação aos achados radiográficos obtivemos 92,5 por cento de bons resultados. O desgaste médio do polietileno foi de 1,4mm. CONCLUSÃO: A utilização da prótese Biomec nesta coorte apresentou bons resultados clínicos e radiográficos.

OBJECTIVE: To analyze the clinical and radiological outcomes of total hip arthroplasty with Biomec prosthesis over a 20-year period (1988 to 2009). METHODS: The patients were evaluated clinically according to the Merle d'Aubigné and Postel functional classification, and submitted to anteroposterior (AP) radiography of the spleen and operated joint in profile. The variables evaluated were acetabular and femoral osteopenia, polyethylene wear, stem migration, follow-up and clinical outcomes. RESULTS: The mean follow-up was 10.6 years (4 to 21years), the sample consisted of 84 patients; 32 male and 52 female; the mean preoperative age was 47 years; we obtained 88 percent good or excellent results in the clinical evaluation. In relation to the radiological findings, we obtained 92.5 percent good results. The mean polyethylene wear was 1.4 mm. CONCLUSION: The use of the Biomec prosthesis in this cohort showed good clinical and radiographic results.

Acompanhamento a médio prazo da reconstrução acetabular com enxerto ósseo liofilizado bovino e dispositivo de reforço / Mid-term follow-up of acetabular reconstruction using bovine freeze-dried bone graft and reinforcement device

OBJETIVO: Relatar a capacidade clínica e radiográfica de integração de enxertos ósseos liofilizados bovinos. MÉTODO: Vinte e cinco pacientes foram incluídos. O período médio de acompanhamento foi de oito anos. Os enxertos foram purificados e liofilizados. A análise clínica baseou-se no escore de Merle d'Aubigné e Postel, e critérios de pontuação estabelecidos para a osteointegração radiográfica foram usados para as análises radiográficas. RESULTADOS: Bons resultados clínicos e radiográficos foram observados em 80 por cento e 72 por cento dos casos, respectivamente. CONCLUSÃO: Enxertos liofilizados bovinos podem ser usados com segurança e adequadamente na revisão acetabular da artroplastia total de quadril.

OBJECTIVE: To report clinical and radiographic graft incorporation capability of bovine freeze-dried bone grafts. METHODS: Twenty five patients were enrolled. The mean follow-up was eight years. Grafts were purified and freeze-dried. Clinical analysis was based on the score of Merle d'Aubigné and Postel and an established score criteria for radiographic bone incorporation was used for radiographic analyses. RESULTS: Good clinical and radiographic results were found in 80 percent and 72 percent of the cases, respectively. CONCLUSION: Bovine freeze-dried grafts can be safely and adequately used in acetabular revision in total hip arthroplasty.

Femoral and acetabular revision using impacted nondemineralized freeze-dried bone allografts.

BACKGROUND: Favorable results have been obtained by the use of deep-frozen bone allografts in total hip arthroplasty. However, owing to the shortage of deep-frozen allografts and the risk of infectious disease, other materials have been studied, such as sterile nondemineralized freeze-dried allografts. The aim of this study was to describe midterm clinical outcomes and radiographic bone incorporation of human freeze-dried bone grafts in 42 revision total hip arthroplasty procedures using cancellous impacted bone grafting. METHODS: This report presented clinical and radiographic evidence of allograft incorporation in 42 hip reconstructions performed between 1996 and 2002. The patient group included 13 (31%) men and 29 (69%) women with mean +/- SD age of 63 +/- 14 years (range 28-80 years). Mean follow-up was 82 months (range 63-127) months. Clinical analysis was based on the D'Aubigné-Postel score. Radiographic incorporation was defined according to specific criteria. RESULTS: The D'Aubigné and Postel criteria showed adequate outcome in 38 (90%) of the patients. The radiographic evaluation revealed that allograft remodeling and incorporation were found in 39 (93.0%) and 36 (86.5%) of acetabular and femoral cases, respectively. The overall graft survival rate at an average follow-up of 8 years (range 5-10 years) was 90%. CONCLUSIONS: Bone grafts obtained by the lyophilization process developed and carried out in our tissue bank provide suitable grafts for revision total hip arthroplasty. Clinical and radiographic midterm results were excellent, indicating that nondemineralized freeze-dried bone allografts are suitable for replacing deep-frozen grafts.

Caracterização físico-química de ossos liofilizados de origem bovina e humana / Physicochemical characterization of bovine and human freeze-dried bones

Objetivo: Verificar as similaridades físico-químicas por meio de análises orgânicas e minerais de ossos liofilizados humanos e bovinos produzidos a partir de um protocolo de processamento desenvolvido pelos autores. Métodos: Determinaram-se os percentuais de extrato etéreo (gordura bruta), proteína total (nitrogênio total) e composição mineral (fósforo total, P2O5 total, cálcio total, sódio total, cinzas e cloretos) das amostras de ossos humanos e bovinos liofilizados. Resultados: O percentual de gordura e de proteína bruta foi de 0.14% e 0.06%, e de 27.20% e 27.53%; enquanto que a composição mineral demonstrou 4.3% e 4.3% de nitrogênio;11.9% e 11.9% de fósforo total; 27.1% e 27.2% de P2O5; 24.6% e 23.7% de cálcio total (relação Ca/P: 2.06 e 1.99); 0.57% e 0.46% de sódio total; 64.8% e 64.3% de cinzas; e 1.3% e 1.3% de cloretos, para as amostras de osso humano e bovino, respectivamente. Nenhuma diferença estatisticamente significativa foi observada entre ossos bovinos e humanos após o processo de liofilização. Conclusão: Avaliações de características físicas e químicas de ossos liofilizados bovinos e humanos claramente demonstraram que estes ossos mantêm virtualmente todas as características de osso original e de similaridades com os ossos humanos, levando a um produto final com boa biocompatibilidade.

Objectives: To determine the physical and chemical characteristics and similarities between lyophilized bone from bovine and human sources manufactured in a semi-industrial scale, according to a modified protocol developed by the authors. Methods: Thepercentages of fat extract (raw fat), total protein (total nitrogen) and mineral composition (total phosphorus, total P2O5, total calcium, total sodium, ashes and chlorides) was determined on the samples of lyophilized human and bovine bones. Results: The percentage of fat extract and raw protein was of 0.14% and 0.06%; and 27.20% and 27.53%; whereas the mineral composition demonstrated 4.3% and 4.3% of nitrogen; 11.9% and 11.9% of total phosphorus; 27.1% and 27.2% of P2O5; 24.6% and 23.7% of total calcium (Ca/P relation: 2.06 and 1.99); 0.57% and 0.46% of total sodium; 64.8% and 64.3% of ashes; and 1.3% and 1.3% of chlorides, for samples of bovine and human bones, respectively. No statistical significant difference was observed between bovine and human bones after the lyophilization process. Conclusion: The assessment of physical and chemical characteristics of bovineand human lyophilized bones has clearly demonstrated that these bones kept virtually all characteristics of a raw bone and keep similarities to human counterparts, yielding an end product with good biocompatibility.

Mid-term follow-up of acetabular reconstruction using bovine freeze-dried bone graft and reinforcement device.

OBJECTIVE: To report clinical and radiographic graft incorporation capability of bovine freeze-dried bone grafts. METHODS: Twenty five patients were enrolled. The mean follow-up was eight years. Grafts were purified and freeze-dried. Clinical analysis was based on the score of Merle d'Aubigné and Postel and an established score criteria for radiographic bone incorporation was used for radiographic analyses. RESULTS: Good clinical and radiographic results were found in 80% and 72% of the cases, respectively. CONCLUSION: Bovine freeze-dried grafts can be safely and adequately used in acetabular revision in total hip arthroplasty.

Osteointegração de enxertos liofilizados impactados / Osteointegration of impacted lyophilized grafts

OBJETIVO: Avaliar clínica e radiograficamente os resultados e a capacidade de osteointegração dos enxertos ósseos liofilizados humano e bovino impactados em revisões de artroplastia total de quadril (RATQ) cimentadas e não-cimentadas. MÉTODOS: Coorte não concorrente de 63 pacientes (66 quadris) submetidos à RATQ com enxerto ósseo liofilizado moído e impactado. O estudo foi realizado no Serviço de Ortopedia e Traumatologia do Hospital de Clínicas de Porto Alegre, entre maio/1997 e setembro/2004. Os pacientes foram divididos em dois grupos: Grupo 1 (n=35), enxerto de origem humana; Grupo 2 (n=31), enxerto de origem bovina. O tempo médio de seguimento foi de 59 meses. Os enxertos ósseos liofilizados foram produzidos segundo protocolo desenvolvido pelos autores. A análise clínica baseou-se no escore de Merle, d'Aubigné e Postel; a radiográfica, nos critérios de radioluscência, densidade, formação de trabeculado ósseo, migração dos componentes e floculação, formulando-se um escore radiográfico de osteointegração. RESULTADOS: Não foram encontradas diferenças clínicas ou radiográficas relevantes entre os grupos, obtendo-se em torno de 85 por cento de integração do enxerto, tanto no componente acetabular quanto femoral. CONCLUSÕES: Os enxertos ósseos liofilizados de origem bovina ou humana, produzidos segundo este protocolo, não acarretaram nenhum prejuízo aos pacientes, tendo o enxerto bovino apresentado resultados similares ao humano.

OBJECTIVE: The purpose of the study was to provide a clinical and X-ray based evaluation of the results and osteointegration ability of lyophilized human and bovine bone grafts. METHODS: This is a non-concurrent cohort trial of 63 patients (66 hips) submitted to revision total hip arthroplasty (RTHA) using impacted freeze-dried human and bovine cancellous bone grafts. The study was carried out in the Hospital de Clinicas de Porto Alegre from May 1997 to September 2002. The patients were divided in two groups: Group 1 (n=35), composed by those receiving human grafts, and Group 2 (n=31), receiving bovine grafts. The mean follow-up time was 33 months. The grafts were purified and lyophilized using a protocol developed by the authors. The clinical analysis was based on Merle, d'Aubigné and Postel's scores; while the radiographic analysis was based on an established score for radiographic bone incorporation. RESULTS: No clinical or radiographic differences were found between the groups, and both groups showed an overall osteointegration rate of 85 percent both in the acetabular and in the femoral component. CONCLUSIONS: Impacted lyophilized human and bovine bone grafts produced by following to the proposed protocol did not cause damage to the patients. Results obtained with both bovine and human grafts were similar.

In vitro and in vivo evaluation of lyophilized bovine bone biocompatibility.

INTRODUCTION: The use of bone grafts in orthopedic, maxillofacial and dental surgery has been growing. Nevertheless, both fresh autografts and frozen allografts have limitations, and therefore, alternative synthetic or natural biomaterials, such as processed and lyophilized bovine bone graft have been developed. OBJECTIVE: To evaluate in vitro and in vivo biocompatibility of lyophilized bovine bone manufactured in a semi-industrial scale, according to a modifical protocol developed by the authors. METHODS: Samples of bovine cancellous bone were processed according to a protocol developed by Kakiuchi et al., and modified to process samples of bovine cancellous bone. The following trials were performed: in vitro cytotoxicity, in vivo acute systemic toxicity, in vivo oral irritation potential, in vitro pyrogenic reaction, and bioburden. RESULTS: The in vitro evaluation of lyophilized bovine cancellous bone revealed an absence of cytotoxicity in 100% of the samples. Regarding in vivo evaluation of acute systemic toxicity, neither macroscopic abnormalities nor deaths were noted in the animals. Pyrogenicity was not greater than 0.125 UE/ml in any of the samples. The bioburden revealed negative results for microbial growth before sterilization. Regarding the oral irritation potential, in vivo evaluation at 24 and 72 hours showed that the animals had no edema or erythema on the oral mucosa. CONCLUSION: The protocol changes established by the authors to prepare lyophilized bovine cancellous bone at a semi-industrial scale is reproducible and yielded a product with excellent biocompatibility.

Caracterização de uma haste femoral de Ti-6Al-4V não cimentada / Characterization of a cementless Ti-6Al-4V femoral stem

O objetivo deste estudo foi determinar a viabilidade de produção de uma prótese femoral de titânio garantindo a qualidade da matéria prima e as características das superfícies. Um protótipo foi criado pelo Método de Elementos Finitos em AutoCad® 2000. A simulação dos esforços demonstrou uma tensão de von Mises 8,1 vezes menor que a tensão crítica para escoamento do material. Na determinação dos constituintes metálicos, obteve-se: Fe  =   0,06%, Al  = 6,20%, V  = 3,57%, O  = 0,115%, N  = 0,003%, H  = 0,010%, e ausência de metais pesados. As propriedades elasto-plásticas da amostra tiveram valor médio de dureza de 4,45 (3,92 a 4,79) GPa e o módulo de elasticidade variou de 112,12 a 140,77  GPa (média  = 134,33). O coeficiente de rugosidade médio (DP) no cone foi de 0,60  (0,03) μm; na região jateada de 12,2 (0,8) μm e na ponta de 0,41 (0,01) μm. Nos ensaios de fadiga e de corrosão não foram observadas alterações. A análisegranulométrica do pó do material depositado demonstrou predominância de partículas médias (75  μm a 180  μm; 84%). A espessura da camada do material depositado apresentou valor médio de 52,7  μm (0 a 318  μm), porosidade média de 16% (variandode 3% a 41%), poros de diâmetro médio de 88,5  μm e profundidade média de 28,2  μm. A tensão (força por unidade de área) de adesão da camada porosa depositada revelou valoresde 15 a 17  MPa. Em conclusão, os resultados dos testes e ensaios técnicos estão dentro das normas internacionalmente recomendadas e padronizadas para implantes metálicos em titânio estando essa prótese de acordo com os padrões internacionaisde qualidade e segurança.

The objective of this work was to study the feasibility of manufacturing a cementless femoral prosthesis in Brazil, in compliance with internationalstandards of quality assurance. A virtual prototype by the Finite Elements Model in AutoCad® 2000 was assessed and demonstrated a von Mises tension 8.1 below the deformation point. In determining the metallic components, the percentages were Fe  = 0.06%, Al  = 6.20%, V  = 3.57%, O  = 0.115%, N  = 0.003%, H  = 0.010% without any contamination due to heavy metals. The elasto-plastic properties showed an average value of hardness of 4.45 (3.92 to 4.79) GPa and elasticity module varied from 112.12 to 140.77  GPa (mean  = 134.33). The average coefficient of roughness (SD) in the cone was 0.60 (0.03) μm, 12.2 (0.8) μm in the plasma spray coating region, and 0.41 (0.01) μm in the tip. In the assays for fatigue and corrosion no changes were observed. The grain size analysis of the deposited material dust demonstrated predominantly (84%) medium size particles (75  μm to 180  μm). The thickness of the deposited material layer presented average value of 52.7  μm (0 to 318  μm), average porosity of 16% (varying from 3% to 41%) and pores of average diameterof 88.5  μm and average depth of 28.2  μm. The force of adhesion of the deposited porous layer showed values between 15  and  17  MPa. Results were in accordance with the norms and tests internationally recommended and standardized for metallic implants in titanium alloy and  the femoral prosthesis manufactured with national technology was in accordance with international standards of design, quality and safeness.

Acetabular reconstruction with human and bovine freeze-dried bone grafts and a reinforcement device.

BACKGROUND: This is a cohort trial (1997-2005) of 49 patients submitted to an acetabular component revision of a total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts (H&FDBG) and a reinforcement device. OBJECTIVE: To compare clinical/radiographic graft incorporation capability between cancellous bone grafts. PATIENTS/METHODS: There were two groups: I (n=26) receiving human grafts and II (n=25) receiving bovine grafts. The average follow-up times were 55 and 49 months, respectively. Clinical analysis was based on the Merle d'Aubigné and Postel score, and the radiographic analysis involved an established score based on Conn's et al. criteria for radiographic bone incorporation. RESULTS: No clinical/radiographic differences were found between the groups and both showed an overall rate of 88.5% and 76% of graft incorporation (p=0.424). CONCLUSION: The results presented here are comparable to those in the literature with the use of deep-FG. Therefore, cancellous bone grafts can be safely and adequately used in acetabular component revision in total hip arthroplasty.

Acetabular reconstruction with human and bovine freeze-dried bone grafts and a reinforcement device

BACKGROUND: This is a cohort trial (1997-2005) of 49 patients submitted to an acetabular component revision of a total hip arthroplasty, using impacted human and bovine freeze-dried cancellous bone grafts (H&FDBG) and a reinforcement device. OBJECTIVE: To compare clinical/radiographic graft incorporation capability between cancellous bone grafts. PATIENTS/METHODS: There were two groups: I (n=26) receiving human grafts and II (n=25) receiving bovine grafts. The average follow-up times were 55 and 49 months, respectively. Clinical analysis was based on the Merle d'Aubigné and Postel score, and the radiographic analysis involved an established score based on Conn's et al. criteria for radiographic bone incorporation. RESULTS: No clinical/radiographic differences were found between the groups and both showed an overall rate of 88.5 percent and 76 percent of graft incorporation (p=0.424). CONCLUSION: The results presented here are comparable to those in the literature with the use of deep-FG. Therefore, cancellous bone grafts can be safely and adequately used in acetabular component revision in total hip arthroplasty.