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Three-dimensional printing is a rapidly growing manufacturing method for orthopaedic implants and it is currently thriving in several other engineering industries. It enables the variation of implant design and the construction of complex structures which can be exploited in orthopaedics and other medical sectors. In this review, we develop the vocabulary to characterise 3D printing in orthopaedics from terms defined by industries employing 3D printing, and by fully examining a 3D-printed off-the-shelf acetabular cup (Fig. 1). This is a commonly used 3D-printed implant in orthopaedics, and it exhibits a range of prominent features brought about by 3D printing. The key features and defects of the porous and dense regions of the implant are clarified and discussed in depth to determine reliable definitions and a common understanding of characteristics of 3D printing between engineers and medical experts in orthopaedics. Despite the extensive list of terminology derived here, it is clear significant gaps exist in the knowledge of this field. Therefore, it is necessary for continued investigations of unused implants, but perhaps more significantly, examining those in vivo and retrieved to understand their long-term impact on patients and the effects of certain features (e.g. surface-adhered particles). Analyses of this kind will establish an understanding of 3D printing in orthopaedics and additionally it will help to update the regulatory approach to this new technology.

The experiment was carried out to investigate the effect of feed withholding in the very early life ofbird on its compensatory growth capacity and fat parameters. A total of 60 mixed-sexes of one day oldRoss chicks were used in the experiment conducted with completely randomized design of 2 differentfeeding times after hatching, i.e.: T1: given access to feed and water ad libitum immediately afterhatching until 35d of age; and T2: withheld from feed (fasted) but not from water for 48h after hatchingand then fed ad libitum until d35. The birds were weighed at the start of experiment and weeklythereafter, and DWG was then calculated. Feed intakes and FCR were also recorded weekly. At d36,abdominal fat was taken out from 2 birds per pen and was weighed. Breast meat (skinless) from thesame birds was also sampled for total FA analysis. Final BW (d35) and total feed consumption of earlyfastedbirds were 1935.17±43.90 kg and 2745.55±47.48 kg and those of unfasted birds were2019.00±50.85 kg and 2910.84±128.10 kg, respectively. FCR of early-fasted and unfasted birds at d35were 1.42±0.03 and 1.45±0.07. The magnitude difference of DWG between early-fasted and unfastedbirds was 27% at d7, whereas at d35 the difference was only 4.5%. Abdominal fat percentage to live BWof early-fasted birds was 1.65±0.09% (male) and 1.60±0.10% (female) and that of unfasted birds was2.00±0.19% (male) and 1.89±0.38% (female). Total FA contained in meat of early-fasted and unfastedbirds were 0.82±0.10 and 0.85±0.10 g/100gDM. Overall, BW and feed consumption of early-fastedbirds were significantly lower (P0.05) between early-fasted and unfasted birds. Inconclusion, holding birds without feed following hatch (under practical conditions) may limit thecompensatory growth capacity of birds in the later age. Fasting applied in the very early life of broilerleads to impairment of cell hyperplasia resulting in permanent stunting. Abdominal fat and total FAcontained in meat might not be affected by fasting for 48h after hatching. The degree or duration of feedwithholding (for 48h after hatching) might not sufficient to reduce adipocyte proliferation or the numberof precursor adipocytes.

This study was carried out to investigate the effect of different levels of Chlorella sp. in the form ofmeal administrated in the diet of broilers throughout their life upon FA profile of the breast muscle,mucosal secretory IgA (sIgA) concentration and production index (PI) of broiler. Allotted in 18 pens, thetotal of 90 Ross day old chicks were assigned in completely randomized design by 3 of dietarytreatments (T1: control (basal diet without enrichment of Chlorella sp.); T2: basal diet enriched with 5-gChlorella sp./kg feed; T3): basal diet enriched with 10-g Chlorella sp./kg feed. At d-36, skinless breastmeat was collected for FA determination. Practical standard of vaccination was performed to activateantibodies production and at d-36 gut mucosa was collected for sIgA analysis. Chlorella sp.administration had no significant effect (P>0.05) on the FA profile of breast muscle, mucosal sIgAconcentration and producton index of broiler. In conclusion, the level and ratio between n-3 to n-6polyunsaturated fatty acids (PUFA) as well as the nature of dietary PUFA source determine tissue PUFAcomposition. Beside through eicosanoid, Chlorella sp. may affect mucosal sIgA production throughcytokines mediated effect. Although Chlorella sp. administration does not improve the production indexof broiler, this treatment may produce broiler meat with lower fat content.

Abstract Background Three-dimensional computed-tomography (3D-CT) planning for primary Total Hip Arthroplasty (THA) typically uses the external femoral surface; as a result, it is difficult to predict the prosthetic femoral version (PFV) for uncemented femoral stems that press-fit to the internal surface of the bone. Cemented fixation allows the surgeon to adjust the version independent of the internal femoral anatomy. We aimed to better understand the effect of the fixation type on PFV. Methods This was a case series study including a total of 95 consecutive patients (106 hips), who underwent uncemented (n = 81 hips) and cemented (n = 25 hips) primary THA using the posterior approach. The surgeon aimed for a PFV of 20°. Our primary objective was to compare PFV in both groups; our secondary objective was to evaluate the clinical outcomes. Results The mean (± SD) PFV was 13° (± 9°) and 23° (± 8°) for the uncemented and cemented THA groups (P

CT is the principal imaging modality used for the pre-operative 3D planning and assessment of total hip arthroplasty (THA). The image quality offered by CT has a radiation penalty to the patient. Higher than necessary radiation exposure is of particular concern when imaging young patients and women of childbearing age, due to the greater risk of radiation-induced cancer in this group. A harmonised low-dose CT protocol is needed, evidenced by the huge variability in the 17 protocols reviewed. The majority of the protocols were incomplete, leading to uncertainty among radiographers when performing the scans. Only three protocols (20%) were optimised for both ‘field of view’ and image acquisition parameters. 10 protocols (60%) were optimised for ‘field of view’ only. These protocols included imaging of the relevant landmarks in the bony pelvis in addition to the knees – the reference for femoral anteversion. CT parameters, including the scanner kilovoltage (kV), milliamperage–time product (mAs) and slice thickness, must be optimised with a ‘field of view’ that includes the relevant bony landmarks. The recommended kV and mAs values were very wide ranging from 100 to 150 and from 100 to 250, respectively. The large variability that exists amongst the CT protocols illustrates the need for a more consistent low-dose CT protocol for the planning of THA. This must provide an optimal balance between image quality and radiation dose to the patient. Current CT scanners do not allow for measurements of functional pelvic orientation and additional upright imaging modalities are needed to augment them.

In recent decades, agricultural intensification has led to a strong decline in biodiversity. Field margins act as shelters and dispersal corridors for biodiversity in highly disturbed landscapes, and are critical to the maintenance of ecosystem services. However, they are also impacted by agricultural practices in neighboring fields. Agricultural impacts are often studied at field to landscape scales, and rarely across biogeographic regions. One of the challenges in large-scale studies is the lack of standardized monitoring schemes including both biodiversity and accurate estimation of agricultural practices. Here, we take advantage of a national monitoring scheme in 462 sites in France, to assess the effects of agricultural practices on field margin flora at different extents and resolutions. We used spatial simultaneous autoregressive and generalized dissimilarity models to assess the response of plant richness and composition to climatic, soil and landscape conditions, and to agricultural (fertilization, herbicides) and margin management drivers. Analyses were repeated at the site-level, 40 and 75 km resolutions, and at regional and national extents. We found that the impact of agricultural practices on species richness was most important at the site-level, whereas climate and crop diversity became more important at the 75 km resolution. Compositional variations responded differently, with climate being more important at the site-level, and fertilization and crop diversity at the coarsest resolution. There was a strong variation in the variance explained by models among regions, but climate effects were weaker within biogeographic units compared to the national level, and different agricultural practices stood out as influential in different regions, suggesting that the regional context is fundamental in determining plant community structure. To efficiently conserve biodiversity, we therefore recommend the implementation of agricultural measures adapted to each region.

Abstract Background Implantation of the femoral component with suboptimal version is associated with instability of the reconstructed hip joint. High variability of Prosthetic Femoral Version (PFV) has been reported in primary Total Hip Arthroplasty (THA). Three-dimensional (3D) Patient-Specific Instrumentation (PSI) has been recently developed and may assist in delivering a PFV within the intended range. We performed a pilot study to better understand whether the intra-operative use of a novel PSI guide, designed to deliver a PFV of 20°, results in the target range of PFV in primary cemented THA. Methods We analysed post-operative Computed-Tomography (CT) data of two groups of patients who underwent primary cemented THA through posterior approach; 1. A group of 11 patients (11 hips) for which the surgeon used an intra-operative 3D-printed stem positioning guide (experimental) 2. A group of 24 patients (25 hips) for which the surgeon did not use the guide (control). The surgeon aimed for a PFV of 20°, and therefore the guide was designed to indicate the angle at which the stem was positioned intra-operatively. PFV angles were measured using the post-operative 3D-CT models of the proximal femurs and prosthetic components in both groups. Our primary objective was to compare the PFV in both groups. Our secondary objective was to evaluate the clinical outcome. Results Mean (± SD) values for the PFV was 21.3° (± 4.6°) and 24.6° (± 8.2°) for the experimental and control groups respectively. In the control group, 20% of the patients reported a PFV outside the intended range of 10° to 30° anteversion. In the experimental group, this percentage dropped to 0%. Satisfactory clinical outcome was recorded in both groups. Conclusion The intra-operative use of a PSI PFV guide helped the surgeon avoid suboptimal PFV in primary cemented THA. Further studies are needed to evaluate if the PSI guide directly contributes to a better clinical outcome.

Resumo Cuidados paliativos promovem qualidade de vida e alívio de sofrimento a pacientes e seus familiares. Nesse contexto, a estratégia a ser adotada na alimentação desses pacientes envolve reflexões da equipe de saúde. Esta pesquisa tem como objetivo verificar a compreensão de profissionais da área hospitalar que atuam no setor de oncologia sobre a nutrição/alimentação de pacientes sob cuidados paliativos. Realizaram-se individualmente entrevistas com dez profissionais, que compreenderam que os cuidados melhoram a qualidade de vida por meio do controle de sintomas físicos, psicológicos e espirituais dos pacientes e seus familiares. Entendem que, além do atendimento das necessidades nutricionais, a alimentação pode proporcionar prazer, conforto e memória afetiva, e que a comunicação é fundamental para um cuidado integrado e humanizado. Assim, julga-se importante desenvolver estratégias de intervenção a partir de treinamentos e da educação continuada desses profissionais.

Abstract Physical activity and a healthy lifestyle are crucial factors for delaying and reducing the effects of sarcopenia. Cycling has gained popularity in the last decades among midlife men. While the cardiovascular benefits of cycling and other endurance exercises have been extensively proved, the potential benefits of lifelong aerobic exercise on muscle health have not been adequately studied. Our aim was to quantify the benefits of cycling in terms of muscle health in middle-aged men, using magnetic resonance imaging. We ran a cross-sectional study involving two groups of middle-aged male adults (mean age 49 years, range 30–65) that underwent Dixon MRI of the pelvis. The groups consisted of 28 physically inactive (PI) and 28 trained recreational cyclists. The latter had cycled more than 7000 km in the last year and have been training for 15 years on average, while the PI volunteers have not practiced sports for an average of 27 years. We processed the Dixon MRI scans by labelling and computing the fat fraction (FF), volume and lean volume of gluteus maximus (GMAX) and gluteus medius (GMED); and measuring the volume of subcutaneous adipose tissue (SAT). We found that the cyclists group had lower FF levels, a measure of intramuscular fat infiltration, compared to the PI group for GMAX (PI median FF 21.6%, cyclists median FF 14.8%, p

Objectives This study aims to quantitatively evaluate whether there are muscle mass differences between male and female recreational cyclists and compare muscle quality and body composition in the pelvis region between two well-matched groups of fit and healthy male and female adults.Methods This cross-sectional study involved 45 female and 42 male recreational cyclists. The inclusion criteria for both groups were to have cycled more than 7000 km in the last year, have an absence of injuries and other health problems, have no contraindication to MRI, and be 30–65 years old. Our main outcome measures were fat fraction, as a measure of intramuscular fat (IMF) content, and volume of the gluteal muscles measured using Dixon MRI. The gluteal subcutaneous adipose tissue (SAT) volume was evaluated as a secondary measure.Results We found that there were no sex differences in the IMF content of gluteus maximus (GMAX, p=0.42), gluteus medius (GMED, p=0.69) and gluteus minimus (GMIN, p=0.06) muscles, despite females having more gluteal SAT (p

Biodiversity is a key component of agricultural ecosystems and belongs to one of the exceeded planetary boundaries. In the quest for innovation to mitigate impact, it is essential to have tools to assess the anthropogenic impact on biodiversity. In this study, we developed a new indicator, I-BIO that aimed to predict the impacts of management practices and the influence of the landscape on overall biodiversity at species group level. I-BIO encompassed four groups: microorganisms, vegetation, invertebrates and vertebrates. This predictive indicator was built using DEXi software that facilitates the design of hierarchical decision trees, based on input variables in the form of qualitative classes, aggregated using utility functions. I-BIO was constructed using data from a long-term platform in Scotland and then applied to two data sets in France and one in Scotland. The results showed that the lowest class is predominant for all branches especially for invertebrates and soil invertebrates. Monte Carlo sampling was used to test for sensitivity. Then, a validation step was carried out to compare I-BIO outputs with real data using data on the four groups from Scottish and French datasets. I-BIO predictions of weed and soil invertebrate abundance conformed to field data. Due to low numbers of samples, validation of microorganisms, flying invertebrates and vertebrates predictions require more data. Future developments of I-BIO will focus on predictions specifically to assess the impact of management on species richness. Avenues for improvement include a better integration of landscape features and the history of agricultural practices as they both have a great influence on biodiversity.

Abstract Background 3D printed patient-specific titanium acetabular cups are used to treat patients with massive acetabular defects. These have highly porous surfaces, with the design intent of enhancing bony fixation. Our aim was to characterise these porous structures in commercially available designs. Methods We obtained 12 final-production, patient-specific 3D printed acetabular cups that had been produced by 6 manufacturers. High resolution micro-CT imaging was used to characterise morphometric features of their porous structures: (1) strut thickness, 2) the depth of the porous layer, (3) pore size and (4) the level of porosity. Additionally, we computed the surface area of each component to quantify how much titanium may be in contact with patient tissue. Statistical comparisons were made between the designs. Results We found a variability between designs in relation to the thickness of the struts (0.28 to 0.65 mm), how deep the porous layers are (0.57 to 11.51 mm), the pore size (0.74 to 1.87 mm) and the level of porosity (34 to 85%). One manufacturer printed structures with different porosities between the body and flange; another manufacturer had two differing porous regions within the body of the cups. The cups had a median (range) surface area of 756.5 mm2 (348 – 1724). Conclusions There is a wide variability between manufacturers in the porous titanium structures they 3D print. We do not currently know whether there is an optimal porosity and how this variability will impact clinically on the integrity of bony fixation; this will become clearer as post market surveillance data is generated.

Background:. The management of massive acetabular defects at the time of revision hip surgery is challenging. Severe pelvic bone loss and the heterogeneity and quality of the remaining bone stock can compromise the fixation and mechanical stability of the implant. Methods:. We reviewed a database of consecutive patients who had undergone acetabular reconstruction with the use of a custom 3D-printed implant with a dual-mobility bearing for the treatment of Paprosky type-3B defects between 2016 and 2019. Functional and radiological outcomes were assessed. Results:. A total of 26 patients (17 women and 9 men) with a minimum follow-up of 36 months (median, 53 months; range, 36 to 77 months) were identified. The median age at surgery was 69 years (range, 49 to 90 years), and 4 patients had pelvic discontinuity. The cumulative implant survivorship was 100%. The median Oxford Hip Score improved significantly from 8 (range, 2 to 21) preoperatively to 32 (range, 14 to 47) postoperatively (p = 0.0001). One patient had a transient sciatic nerve palsy, 1 hip dislocated 6 months postoperatively and was managed nonoperatively, and 1 infection recurred. No patient had a fracture. Radiographic evaluation showed bone ingrowth at the bone-implant interface in 24 patients (92%) at ≥12 months of follow-up and showed no evidence of implant loosening or migration at the latest follow-up (3 to 6 years). Conclusions:. Excellent functional improvement, implant survivorship, and osseointegration were recorded in the patient cohort. Accurate preoperative planning and the adoption of custom 3D-printed implants showed promising results in complex revision hip surgery. Level of Evidence:. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

The placement of acetabular implant components determines the short- and long-term outcomes of total hip replacement (THR) and a number of tools have been developed to assist the surgeon in achieving cup orientation to match the surgical plan. However, the accuracy and precision of 3D-CT for the measurement of acetabular component position and orientation is yet to be established. To investigate this, we compared measurements of cobalt chrome acetabular components implanted into 2 different bony pelvic models between a coordinate measuring Faro arm and 3 different low dose CT images, including 3D-CT, 2D anterior pelvic plane (APP) referenced CT and 2D scanner referenced (SR) CT. Intra-observer differences were assessed using the Intraclass correlation coefficient (ICC). The effect of imaging the pelvis positioned in 3 different orientations within the CT scanner was also assessed. The measured parameters were the angles of inclination and version. 3D-CT measurements were found to closely match the “true values” of the component position measurements, compared with the 2D-CT methods. ICC analysis also showed good agreement between the coordinate measuring arm (CMA) and 3D-CT but poor agreement between the 2D SR method, in the results from two observers. When using the coordinate system of the CT scanner, the measurements consistently produced the greatest error; this method yielded values up to 34° different from the reference digitising arm. However, the difference between the true inclination and version angles and those measured from 3D APP CT was below half a degree in all cases. We concluded that low radiation dose 3D-CT is a validated reference standard for the measurement of acetabular cup orientation.

Objetivo: Analisar o estado nutricional e o tempo de jejum pré-operatório de pacientes oncológicos submetidos a procedimentos cirúrgicos. Método: Estudo de abordagem quantitativa, realizado com pacientes com diagnóstico de câncer de cabeça e pescoço e/ou trato gastrointestinal submetidos à cirurgias durante o mês de novembro de 2020. Foi aplicado questionário para coleta dos dados clínicos, cirúrgicos e de trajetória terapêutica e realizada avaliação nutricional por meio da antropometria (peso, estatura, circunferência da panturrilha) e aplicação da Avaliação Subjetiva Global Produzida pelo Próprio Paciente (ASG-PPP). As variáveis foram analisadas de acordo com a natureza do dados. Resultados: Foram avaliados 20 pacientes com média de idade de 62,55 anos, sendo 55% do sexo feminino e 80% apresentaram desnutrição moderada ou grave pela ASG-PPP. O tempo médio de jejum pré-operatório foi de 14,21 horas. O tempo médio entre o diagnóstico e a realização da cirurgia foi de 158 dias. Não houve diferença estatística entre o tempo de trajetória terapêutica e o diagnóstico nutricional. Conclusão: O tempo de jejum pré-operatório ultrapassou as orientações de 8 a 12 horas convencionais e 80% dos pacientes apresentavam desnutrição moderada ou grave segundo a ferramenta ASG-PPP. Evidencia-se a necessidade de desenvolvimento protocolos de abreviação do tempo de jejum pré-operatório, proporcionando melhores condições para a recuperação pós-operatória. Palavras-chave: Jejum. Neoplasias. Estado nutricional. Oncologia.

Abstract Background With the Persona® knee system a novel anatomic total knee design was developed, which has no pre-coating, whereas the predecessor knee system is pre-coated with polymethylmethacrylate (PMMA). Joint registry data have shown no decrease in risk of aseptic revision of PMMA pre-coated tibial components compared with non-pre-coated implants. The aim of this retrieval study was to compare the amount of cement adhesions, geometry and surface features between the two knee designs and to correlate them with the underlying reason for revision surgery. Methods Retrieval analysis was performed of 15 NexGen® and 8 Persona® fixed-bearing knee implants from the same manufacturer retrieved from two knee revision centres. A photogrammetric method was used to grade the amount of cement attached to the tibial tray backside. The geometry and dimensions of the tibial trays, tray projections and peripheral lips were measured using digital callipers and compared between the two different designs. To measure the surface roughness on the backside of the tibial tray, a contact profilometer was used. To investigate differences between the two designs statistical analyses (t-test) were performed. Results All Persona® trays showed evidence of cement adhesion with a % area of 75.4%; half of the NexGen® trays had cement adhesions, with a mean value of 20%. There was a significant difference in the percentage of area covered by cement between the two designs (p

Edge-wear in acetabular cups is known to be correlated with greater volumes of material loss; the location of this wear pattern in vivo is less understood. Statistical shape modelling (SSM) may provide further insight into this. This study aimed to identify the most common locations of wear in vivo, by combining CT imaging, retrieval analysis and SMM. Shape variance was described in 20 retrieved metal-on-metal acetabular surfaces. These were revised after a mean of 90 months, from 13 female and seven male patients. They were positioned with a mean inclination and anteversion of 53° and 30°, respectively. Their orientation, in vivo, was established using their stabilising fins, visible in pre-revision CT imaging. The impact of wear volume, positioning, time, gender and size on the in vivo location of wear was investigated. These surfaces had a mean wear volume of 49.63 mm3. The mean acetabular surface displayed superior edge-wear centred 7° within the posterosuperior quadrant, while more of the volumetric wear occurred in the anterosuperior quadrant. Components with higher inclination had greater superior edge-wear scars, while a relationship was observed between greater anteversion angles and more posterosuperior edge-wear. This SSM method can further our understanding of hip implant function, informing future design and may help to refine the safe zone for implant positioning.

Femoral neck osteotomy creates a critical anatomical landmark for surgeons performing primary Total Hip Arthroplasty (THA); it affects the final height and position of the femoral component. Patient Specific Instrumentation (PSI) has been developed to guide the osteotomy. We aimed to assess the accuracy of a patient-specific (PS) femoral osteotomy guide in primary THA using three-dimensional (3D) computed tomography (CT) analysis. We included pre- and post-operative CT data of 103 THAs. All patients underwent 3D planning to define the optimal femoral neck osteotomy level. Our primary objective was to quantify the discrepancy between the achieved and planned osteotomy level; our secondary objective was to evaluate the clinical outcome. The median (Interquartile Range—IQR) discrepancy between the achieved and planned osteotomy level was 0.3 mm (−1 mm to 2 mm). We found a strong positive correlation between the planned and achieved osteotomy level (R2 = 0.9, p < 0.001). A satisfactory clinical outcome was recorded. Our findings suggest that surgeons can use 3D-printed PS guides to achieve a femoral neck osteotomy with a high level of accuracy to the plan.