ABSTRACT Objective: To compare anatomic anterior cruciate ligament (ACL) reconstruction between two tunnel positions in knees with isolated ligament tears. Methods: Anatomic ACL reconstruction was performed, from hip-to-toe, on 15 fresh cadaveric specimens. No associated lesions were created to enhance knee instability. The protocol was conducted in three states: (1) complete isolated ACL deficiency; (2) anatomic femoral and tibial anteromedial ACL reconstruction (AM REC); and (3) anatomic femoral and tibial central ACL reconstruction (Central REC). The reconstruction protocols were randomly assigned. The continuous mechanized pivot-shift test was recorded dynamically with a tracking system. Results: The Central REC group showed a smaller degree of internal rotation (0.6° ± 0.3° vs. 1.8° ± 0.3°, respectively, P < 0.05) and no difference in anterior translation (4.7 mm ± 0.4 mm vs. 4.5 mm ± 0.4 mm, respectively, P > 0.05) in the pivot-shift test, compared with the AM REC group. Conclusion: The central anatomic ACL reconstruction resulted in greater restriction of internal rotation than the anteromedial anatomic ACL reconstruction. Experimental Study on Cadaver.

RESUMO Objetivo: Comparar a reconstrução anatômica do ligamento cruzado anterior (LCA) entre duas posições de túnel em joelhos com lesões isoladas do ligamento. Métodos: A reconstrução anatômica do LCA foi realizada, do quadril aos pés, em 15 peças anatômicas de cadáveres frescos. Não foram criadas lesões associadas para intensificar a instabilidade do joelho. O protocolo foi realizado em três estados: (1) deficiência isolada completa do LCA; (2) reconstrução anatômica femoral e anteromedial tibial do LCA (AM REC); e (3) reconstrução anatômica femoral e central tibial do LCA (Central REC). Os protocolos de reconstrução foram atribuídos aleatoriamente. O teste de pivot-shift mecanizado contínuo foi registrado dinamicamente com um sistema de rastreamento. Resultados: O grupo Central REC apresentou menor grau de rotação interna (0,6° ± 0,3° vs. 1,8° ± 0,3°, respectivamente, p < 0,05) e nenhuma diferença na translação anterior (4,7 mm ± 0,4 mm vs. 4,5 mm ± 0,4 mm, respectivamente, p > 0,05) no teste de pivot-shift, comparado ao grupo AM REC. Conclusão: A reconstrução anatômica central tibial do LCA resultou em maior restrição da rotação interna do que a reconstrução anteromedial tibial do LCA. Estudo em Cadáver Experimental.

Abstract The worldwide consumption of electric energy destined for air conditioners, expected to triple by 2050, can be lessened by geothermal piles, which transfer heat from the internal environment of buildings to the subsoil. This paper shows the influence of pile geometry and properties of soil, pile, and pipe materials on the heat transfer of a geothermal pile to the surrounding soil, to support design from the viewpoint of thermal performance optimization. A numerical model was developed with ANSYS CFX 19.2, a high-performance Computational Fluid Dynamics tool, and calibrated using data from a thermal response test performed in a saturated sandy soil in São Paulo, Brazil. A parametric analysis was carried out varying pile length, diameter, and slenderness; soil and pile material conductivities; degree of saturation; fluid inlet temperature; fluid flow rate; and pipe thermal resistance. Results show that the fluid inlet temperature is the most influential parameter on the thermal performance of the pile. Heat transfer grows when geometrical parameters (diameter and length) are increased mainly due to an increase in heat exchange surface area, whereas the normalized heat transfer rate per unit of surface area of the pile is practically unaltered. Higher soil, pipe and pile thermal conductivities improve thermal performance. The degree of saturation increases the thermal conductivity of the soil; however, the effect is not remarkable on the system’s thermal performance for saturation degrees higher than 20%. The fluid flow must be turbulent but increases above a certain flow rate do not improve the thermal performance.

Objective: To validate intra- and inter-class correlation coefficients of a transparent 3D-TC protocol and investigate relationships between different axial rotations.Methods: Twenty unilateral knee TCs (iSite - Philips) were evaluated by means of a transparent 3D-TC OsiriX Imaging Software (v.3.9.4), 3D MPR protocol. Mathematical model of femoral tunnel projections acquired on vertical and horizontal rotations from -20 to +20 degrees. Height (h'/H) and length (t'/T) of tunnel projections have been analyzed by the Bernard and Hertel's method.Statistics: power of study=80%, ICC, ANOVA, p<0.05 (SPSS-19). Results: Transparent 3D-TC showed high reliability of both intra-observer (h'/H=0.941; t'/T=0.928, p<0.001) and inter-observer (h'/H=0.921; t'/T=0.890, p<0.001) ICC. ACL Length (t'/T) and Height (h'/H) projections were statistically different on vertical and horizontal rotations: p=0.01 and p<0.001, respectively.Conclusion: This new transparent 3D-TC protocol is an accurate and reproducible method that can be applied for ACL femoral tunnel or footprint measurement with high ICC reliability. Level of Evidence II, Descriptive Laboratory Study.

INTRODUÇÃO: Os estudos sobre a razão de custo-efetividade dos stents farmacológicos (SFs) são escassos. Nosso objetivo foi avaliar os resultados e comparar os custos (razão custo-efetividade incremental - RCEI) por reestenose evitada entre SFs e stents não-farmacológicos (SNFs) utilizando o escore de propensão. MÉTODOS: Incluímos na análise 220 pacientes tratados consecutivamente, dos quais 111 com SFs e 109 com SNFs. O escore de propensão foi usado para ajustar o efeito da intervenção por meio de pareamento, estratificação e ponderação. RESULTADOS: Predominaram pacientes do sexo masculino (67,7% vs. 66,9%; P = 0,53), com média de idade de 65,9 anos. Pacientes tratados com SFs apresentaram maior frequência de diabetes (54% vs. 17,4%; P < 0,001) e doença triarterial (18,9% vs. 10,1%; P = 0,029) e pior função ventricular (54,1% vs. 22%; P < 0,0001). O diâmetro dos stents foi de 2,76 ± 0,35 mm vs. 2,91 ± 0,47 mm (P = 0,006) e a soma do comprimento dos stents foi de 37,6 ± 23 mm vs. 24,8 ± 15,8 mm (P < 0,0001). Reestenose ocorreu em 6,3% vs. 12,8% dos pacientes (P = 0,099) e em 4,1% vs. 9,8% das lesões (P = 0,048). Houve incremento de custo de R$ 9.590,00 e a RCEI foi de R$ 147.538,00 por reestenose evitada (acima do limiar da Organização Mundial da Saúde). Entretanto, utilizando o escore de propensão, as variáveis que melhor classificaram os pacientes para SFs e apresentam RCEI máxima de R$ 4.776,96 foram idade > 72 anos, diabetes e lesões com diâmetro < 3,2 mm e comprimento > 18 mm. CONCLUSÕES: Apesar de os SFs não terem sido custo-efetivos na população em geral, o escore de propensão demonstrou que em idosos, diabéticos e pacientes com lesões longas ou vasos de fino calibre o uso de SFs foi custo-efetivo.

BACKGROUND: Studies on the cost-effectiveness ratio of drug-eluting stents (DES) are rare. Our objective was to evaluate the results and compare costs (incremental cost-effectiveness ratio - ICER) per restenosis avoided between DES and bare metal stents (BMS) using the propensity score. METHODS: Two hundred and twenty consecutive patients were included in the study, of which 111 were treated with DES and 109 with BMS. The propensity score was used to adjust the effect of the intervention, by means of matching, stratification and weighing. RESULTS: Most patients were male (67.7% vs. 66.9%; P = 0.53), with a mean age of 65.9 years. Patients treated with the DES had a higher rate of diabetes (54% vs. 17.4%; P < 0.001), three-vessel disease (18.9% vs. 10.1%; P = 0.029) and poor ventricular function (54.1% vs. 22%; P < 0.0001). The diameter of stents was 2.76 ± 0.35 mm vs. 2.91 ± 0.47 mm (P = 0.006) and the sum of the lengths of stents was 37.6 ± 23 mm vs. 24.8 ± 15.8 mm (P < 0.0001). Restenosis was observed on 6.3% vs. 12.8% of the patients (P = 0.099) and in 4.1% vs. 9.8% of the lesions (P = 0.048). There was an incremental cost of R$ 9,500.00 and the ICER was R$ 147,538.00 per restenosis avoided (above the World Health Organization threshold). However, when the propensity score was used, the variables that best classified patients for DES and had a maximum ICER of R$ 4,776.96 were age > 72 years, diabetes and lesions with diameter < 3.2 mm and length > 18 mm. CONCLUSIONS: Although DES were not cost-effective in the overall population, the propensity score showed that in elderly patients, diabetics and patients with long lesions or small vessels, the use of DES was cost-effective.

FUNDAMENTO: Na literatura nacional há escassez de análises de custo-efetividade, comparando stents farmacológicos (SF) versus não farmacológicos (SNF), no seguimento tardio. OBJETIVO: Estimar a Razão de Custo-Efetividade Incremental (RCEI) entre SF e SNF na coronariopatia uniarterial. MÉTODOS: 217 pacientes (130 SF e 87 SNF), com 48 meses de seguimento (média=26). Desfecho primário: custo por re-estenose evitada, sendo efetividade definida como redução de eventos maiores. O modelo analítico de decisão foi baseado no estudo de Polanczyk et al. Os custos diretos foram aqueles utilizados diretamente nas intervenções. RESULTADOS: A amostra foi homogênea para idade e sexo. O SF foi mais utilizado em diabéticos: 59 (45,4%) vs 16 (18,4%)(p<0,0001) e com história de DAC: 53 (40,7%) vs 13 (14,9%)(p<0,0001). O SNF foi utilizado em lesões mais simples, porém com pior função ventricular. Os SF foram implantados preferencialmente nas lesões proximais: (p=0,0428) e os SNF no 1/3 médio (p=0,0001). Sobrevida livre de eventos: SF=118 (90,8%) vs SNF=74 (85,0%) (p=0,19); Angina: SF=9 (6,9%) vs SNF=9 (10,3%) (NS): Reestenose clínica: SF=3 (2,3%) vs SNF=10 (10,3%) (p=0,0253). Óbitos cardíacos: 2 (1,5%) no SF e 3 (3,5%) no SNF (NS). Custos: a árvore de decisão foi modelada na reestenose. O benefício líquido para SF necessitou de incremento de R$7.238,16. A RCEI foi R$131.647,84 por reestenose evitada (acima do limiar da OMS). CONCLUSÕES: O SF abordou lesões mais complexas. Os resultados clínicos foram similares. A reestenose foi maior no SNF. O SF foi uma estratégia não custo-efetiva.

BACKGROUND: There is a scarcity of cost-effectiveness analyses in the national literature comparing drug-eluting stents (DES) with bare-metal stents (BMS), at late follow-up. OBJECTIVE: To estimate the Incremental Cost-Effectiveness Ratio (ICER) between DES and BMS in uniarterial coronariopathy. METHODS: 217 patients (130 DES and 87 BMS), with 48 months of follow-up (mean = 26 months) were assessed. Primary outcome: cost per prevented restenosis, with effectiveness being defined as the decrease in major events. The analytical model of decision was based on the study by Polanczyk et al. The direct costs were those used directly in the interventions. RESULTS: The sample was homogenous for age and sex. The DES was more used in diabetic patients: 59 (45.4%) vs 16 (18.4%)(p<0.0001) and with a history of coronary artery disease (CAD): 53 (40.7%) vs 13 (14.9%)(p<0.0001). The BMS was more used in simple lesions, but with worse ventricular function. The DES were implanted preferentially in proximal lesions: (p=0.0428) and the BMS in the mid-third (p=0.0001). Event-free survival: DES = 118 (90.8%) vs BMS=74 (85.0%) (p=0.19); Angina: DES=9 (6.9%) vs BMS=9 (10.3%) (NS): Clinical restenosis: DES=3 (2.3%) vs BMS=10 (10.3%) (p=0.0253). Cardiac deaths: 2 (1.5%) in DES and 3 (3.5%) in BMS (NS). Costs: the tree of decision was modeled based on restenosis. The net benefit for the DES needed an increment of R$7,238.16. The ICER was R$131,647.84 per prevented restenosis (above the WHO threshold). CONCLUSIONS: The DES was used in more complex lesions. The clinical results were similar. The restenosis rate was higher in the BMS group. The DES was a non-cost-effective strategy.

The aim of this work is to analyze the carbon monoxide (CO) transport in the human body submitted to several physical activity levels. A complete mathematical model of the human respiratory system was developed, considering the exchanges of CO, oxygen (O2) and carbon dioxide (CO2) in the lung, blood and tissues. The human body was divided in the following compartments: alveolar, pulmonary capillaries, arterial, venous, tissue capillary and tissues. The gas transport in the blood and tissues is represented by empirical equations. The physiological parameters were described in function of physical activity. The model was validated by comparing its results with experimental data of controlled CO exposition. The agreement was excellent. CO concentration curves for critical days of São Caetano do Sul city (SP, Brazil) atmosphere were used as model input. The simulation results for some physical activities show that the more intense the activity, the larger the blood carboxyhemoglobin (COHb) level variations. The COHb level was compared with a CO quality air criteria, which showed to be adequate for low and moderate physical activity levels.