Enhancing Knee MR Image Clarity through Image Domain Super-Resolution Reconstruction.

This study introduces a hybrid analytical super-resolution (SR) pipeline aimed at enhancing the resolution of medical magnetic resonance imaging (MRI) scans. The primary objective is to overcome the limitations of clinical MRI resolution without the need for additional expensive hardware. The proposed pipeline involves three key steps: pre-processing to re-slice and register the image stacks; SR reconstruction to combine information from three orthogonal image stacks to generate a high-resolution image stack; and post-processing using an artefact reduction convolutional neural network (ARCNN) to reduce the block artefacts introduced during SR reconstruction. The workflow was validated on a dataset of six knee MRIs obtained at high resolution using various sequences. Quantitative analysis of the method revealed promising results, showing an average mean error of 1.40 ± 2.22% in voxel intensities between the SR denoised images and the original high-resolution images. Qualitatively, the method improved out-of-plane resolution while preserving in-plane image quality. The hybrid SR pipeline also displayed robustness across different MRI sequences, demonstrating potential for clinical application in orthopaedics and beyond. Although computationally intensive, this method offers a viable alternative to costly hardware upgrades and holds promise for improving diagnostic accuracy and generating more anatomically accurate models of the human body.

Pericapsular Nerve Group Block Leads to Small but Consistent Reductions in Pain Between 18 and 24 Hours Postoperatively in Hip Arthroscopy for Femoroacetabular Impingement Surgery: A Prospective, Randomized Controlled Clinical Trial.

PURPOSE: To investigate whether the use of a pericapsular nerve group (PENG) block would reduce perioperative pain after arthroscopic therapy for femoroacetabular impingement syndrome (FAIS) and to examine opioid requirements and occurrence of postoperative nausea and vomiting (PONV). METHODS: Between May 2022 and October 2022, patients (N = 68) undergoing arthroscopic surgery for FAIS were randomly allocated into 2 groups. The first group received an ultrasound-guided PENG preoperatively with 20 mL of 0.375% ropivacaine and standardized postoperative oral medication. The second group received a sham block preoperatively with 20 mL of 0.9% saline and standardized postoperative oral medication. The primary end point was pain scores (visual analog score [VAS], 0-10) during the first 24 hours postoperatively. To quantify clinical significance of outcome achievement for the VAS pain score, the minimal clinically important difference (MCID) was calculated using the half standard deviation method. The incidence of PONV as well as opioid usage (converted to morphine equivalent) within the first 24 hours were secondary outcomes. RESULTS: Randomization and permission were successfully obtained from 68 participants. From the fifteenth postoperative hour, the PENG group reported significantly less postoperative pain than the control group (24th postoperative hour: VAS pain PENG group 1.3 ± 0.9 [0-3]; 95% confidence interval {CI} 0.4-1.2 vs the VAS pain control group 2.4 ± 1.6 [0-5]; 95% CI 1.4-4.7; P = .009). The VAS pain score threshold for achieving the MCID at 24 hours postoperative was defined as a decrease of 1.1. 27 patients (79%) in the PENG group and 22 patients (65%) in the control group were able to achieve MCID (P = .009). Opioid dosage and postoperative nausea did not differ significantly between groups (P = .987 and P = .655, respectively). Concomitant complications such as falls, hematomas, or weakened muscles did not occur in either group. CONCLUSIONS: According to this study, a PENG block minimally reduced pain after arthroscopic treatment for FAIS between the 18th and 24th postoperative hours. The PENG group achieved significantly more often the pain VAS MCID. However, there was no proof that the PENG group consumed fewer opioids than the control group. Overall, PONV was found at a low and comparable rate. LEVEL OF EVIDENCE: Level I, randomized controlled trial.

Intraoperative visualization of the posterolateral ulnohumeral joint space is reliable to indicate overlengthening in radial head arthroplasty.

INTRODUCTION: Avoiding overlengthening in radial head arthroplasty (RHA) is essential for the prognosis of the elbow joint. An overlengthening from 2 mm is visible due to widening of the anterolateral ulnohumeral joint space but intraoperatively, this particular joint space is difficult to visualize. The commonly used Kocher approach allows visualization of the posterolateral joint space without additional instruments or further surgical release of the already unstable elbow. The aim of our study was to investigate whether the visualization of the posterolateral joint space is also a reliable method to indicate overlengthening in RHA. MATERIAL AND METHODS: RHA was performed in five human cadaveric specimens with the forearm, wrist, and hand intact. The lateral ligament complex was detached and an anatomic transosseous refixation was performed. Six stages of implantation heights were documented: native joint (1), RHA at the anatomic height (2), + 2 mm (3), + 4 mm (4), + 6 mm (5) and - 2 mm (6). Macroscopic measurement and digital image analysis of the posterolateral and anterolateral ulnohumeral joint spaces were performed. RESULTS: All stages of overlengthening showed a significant increase in posterolateral and anterolateral joint space widening (p < 0.05). The posterior and anterior joint space showed excellent intraclass correlation. CONCLUSION: Visualization of the posterolateral aspect of the ulnohumeral joint space is a reliable indicator for overlengthening in RHA without further compromising an already unstable elbow. Correlation to the findings of the anterolateral ulnohumeral joint space in different implants leads to the assumption that visualization of either the anterior or posterior ulnohumeral joint space is universally applicable to determine overlengthening in RHA, regardless of the type of the radial head implant.

A multi-reservoir extruder for time-resolved serial protein crystallography and compound screening at X-ray free-electron lasers.

Serial crystallography at X-ray free-electron lasers (XFELs) permits the determination of radiation-damage free static as well as time-resolved protein structures at room temperature. Efficient sample delivery is a key factor for such experiments. Here, we describe a multi-reservoir, high viscosity extruder as a step towards automation of sample delivery at XFELs. Compared to a standard single extruder, sample exchange time was halved and the workload of users was greatly reduced. In-built temperature control of samples facilitated optimal extrusion and supported sample stability. After commissioning the device with lysozyme crystals, we collected time-resolved data using crystals of a membrane-bound, light-driven sodium pump. Static data were also collected from the soluble protein tubulin that was soaked with a series of small molecule drugs. Using these data, we identify low occupancy (as little as 30%) ligands using a minimal amount of data from a serial crystallography experiment, a result that could be exploited for structure-based drug design.

Deciphering the "Art" in Modeling and Simulation of the Knee Joint: Assessing Model Calibration Workflows and Outcomes.

Model reproducibility is a point of emphasis for the National Institutes of Health (NIH) and in science, broadly. As the use of computational modeling in biomechanics and orthopedics grows, so does the need to assess the reproducibility of modeling workflows and simulation predictions. The long-term goal of the KneeHub project is to understand the influence of potentially subjective decisions, thus the modeler's "art", on the reproducibility and predictive uncertainty of computational knee joint models. In this paper, we report on the model calibration phase of this project, during which five teams calibrated computational knee joint models of the same specimens from the same specimen-specific joint mechanics dataset. We investigated model calibration approaches and decisions, and compared calibration workflows and model outcomes among the teams. The selection of the calibration targets used in the calibration workflow differed greatly between the teams and was influenced by modeling decisions related to the representation of structures, and considerations for computational cost and implementation of optimization. While calibration improved model performance, differences in the postcalibration ligament properties and predicted kinematics were quantified and discussed in the context of modeling decisions. Even for teams with demonstrated expertise, model calibration is difficult to foresee and plan in detail, and the results of this study underscore the importance of identification and standardization of best practices for data sharing and calibration.

Successful use of HTF as a basal fertilization medium during SEcuRe mouse in vitro fertilization.

OBJECTIVE: The ever-increasing number of genetically engineered mouse models highlights the need for efficient archiving and distribution of these lines. Sperm cryopreservation has become the preferred technique for the majority of these models due to its low requirement of costs, time, and experimental animals. Yet, current in vitro fertilization (IVF) protocols either exhibit decreased fertilization efficiency for the most popular C57BL/6 strain, as recently demonstrated by us, or require costly and difficult-to-prepare media, respectively. As a result, we previously developed SEcuRe, a modified IVF protocol with low costs and high fertilization efficiency. The popular basal fertilization medium, Cook's® proprietary "Research vitro fert" (RVF), used in this protocol has recently been discontinued. As a result, the application of the SEcuRe approach and other IVF protocols employing this medium has been severely limited. RESULTS: Here we show that human tubal fluid (HTF), a popular and widely available medium with a known composition, can be used as a basal fertilization medium instead of RVF. Comparison of RVF and HTF during 58 independent SEcuRe IVFs with cryopreserved C57BL/6 sperm revealed equal fertilization and live birth rates. In addition, we demonstrate that HTF has a substantially extended shelf-life by utilizing commercial HTF that was six months past its expiration date, yet did not affect fertilization during IVF or subsequent embryo development. This finding not only increases the economic value of our modified method, but also validates it once more. Our results demonstrate that common, shelf-life extended HTF can be used in SEcuRe IVF in place of now-discontinued RVF medium and ensure the applicability of the method, which we since termed SEcuRe 2.0. Our modified SEcuRe 2.0 strategy will assist researchers to efficiently archive and distribute genetically engineered mouse models in a cost-effective, easily adaptable, and 3R-compliant manner with minimal animal use.

Conventional and living guideline for schizophrenia: barriers and facilitating factors in guideline implementation.

This study aims to investigate the barriers and facilitators to guideline adherence for the print format of the German schizophrenia guideline as well as for the concept of a digital living guideline for the first time. For this purpose, the schizophrenia guideline was transferred to a digital guideline format within the web-based tool MAGICapp. An online survey was performed under participation of mental healthcare professionals (medical doctors, psychologists/psychotherapists, psychosocial therapists, caregivers) in 17 hospitals for psychiatry in Southern Germany and a professional association for German neurologists and psychiatrists. 524 participants opened the survey, 439 completed the demographic questions and commenced the content-related survey and 309 provided complete data sets. Results indicate a higher occurrence of knowledge-related barriers for the living guideline. The print version is associated with more attitude-related and external barriers. Older professionals reported more attitude-related barriers to a living guideline compared to younger professionals. Differences between professions regarding barriers were found for both formats. Various barriers exist for both guideline formats and a need for facilitators was expressed across professions. Many of the mentioned obstacles and facilitators can be more easily addressed with living guidelines. However, also living guidelines face barriers. Thus, the introduction of these new formats alone cannot lead to sustainable behavior change regarding guideline adherence. Yet, living guidelines seem to be a cornerstone to improved and tailored guideline implementation as they facilitate to keep recommendations up to date and to address the need of individual professional groups.

A Narrative Review of Personalized Musculoskeletal Modeling Using the Physiome and Musculoskeletal Atlas Projects.

In this narrative review, we explore developments in the field of computational musculoskeletal model personalization using the Physiome and Musculoskeletal Atlas Projects. Model geometry personalization; statistical shape modeling; and its impact on segmentation, classification, and model creation are explored. Examples include the trapeziometacarpal and tibiofemoral joints, Achilles tendon, gastrocnemius muscle, and pediatric lower limb bones. Finally, a more general approach to model personalization is discussed based on the idea of multiscale personalization called scaffolds.

Reproducibility in modeling and simulation of the knee: Academic, industry, and regulatory perspectives.

Stakeholders in the modeling and simulation (M&S) community organized a workshop at the 2019 Annual Meeting of the Orthopaedic Research Society (ORS) entitled "Reproducibility in Modeling and Simulation of the Knee: Academic, Industry, and Regulatory Perspectives." The goal was to discuss efforts among these stakeholders to address irreproducibility in M&S focusing on the knee joint. An academic representative from a leading orthopedic hospital in the United States described a multi-institutional, open effort funded by the National Institutes of Health to assess model reproducibility in computational knee biomechanics. A regulatory representative from the United States Food and Drug Administration indicated the necessity of standards for reproducibility to increase utility of M&S in the regulatory setting. An industry representative from a major orthopedic implant company emphasized improving reproducibility by addressing indeterminacy in personalized modeling through sensitivity analyses, thereby enhancing preclinical evaluation of joint replacement technology. Thought leaders in the M&S community stressed the importance of data sharing to minimize duplication of efforts. A survey comprised 103 attendees revealed strong support for the workshop and for increasing emphasis on computational modeling at future ORS meetings. Nearly all survey respondents (97%) considered reproducibility to be an important issue. Almost half of respondents (45%) tried and failed to reproduce the work of others. Two-thirds of respondents (67%) declared that individual laboratories are most responsible for ensuring reproducible research whereas 44% thought that journals are most responsible. Thought leaders and survey respondents emphasized that computational models must be reproducible and credible to advance knee M&S.

Between guidelines and clinical trials: evidence-based advice on the pharmacological management of non-specific chronic low back pain.

The pharmacological management of nonspecific chronic low back pain (NCLBP) aims to restore patients' daily activities and improve their quality of life. The management of NCLBP is not well codified and extremely heterogeneous, and residual symptoms are common. Pharmacological management should be considered as co-adjuvant to non-pharmacological therapy, and should be guided by the symptoms reported by the patients. Depending on the individual severity of NCLPB, pharmacological management may range from nonopioid to opioid analgesics. It is important to identify patients with generalized sensory hypersensitivity, who may benefit from dedicated therapy. This article provides an evidence-based overview of the principles of pharmacological management of NCLPB.

Pain and rehabilitation after total hip arthroplasty are approach dependent: results 6 weeks and 2 years after surgery in a multisurgeon, single-center, and prospective cohort study.

PURPOSE: The aim of this study was the evaluation of pain, function, and overall satisfaction after total hip arthroplasty (THA) using three different standard surgical approaches (DAA (direct anterior approach), lateral, and posterior approach) 2 years postoperatively. Additionally, we compared the results with recently published results of the same study population 6 weeks postoperatively. METHODS: In a multisurgeon, prospective, single-center cohort study, a total of initial 188 patients who underwent total hip arthroplasty (THA) between February 2019 and April 2019 were analyzed on pain, function, and satisfaction within the first days, 6 weeks, and 2 years postoperatively according to three different approaches (DAA, lateral, and posterior approach). Our research group recently published results directly and 6 weeks postoperatively. We evaluated the same study collectively 2 years postoperatively and compared the results with the data 6 weeks postoperatively. One hundred twenty-five patients could be included. Outcome parameters for the present study were the pain level according to the visual analogue scale (VAS), the modified Harris hip score (mHHS), and an overall satisfaction scale 2 years postoperatively. RESULTS: Mean overall satisfaction 2 years postoperatively was 9.7 ± 1 (3-10). Satisfaction was significantly better for the DAA than for the lateral approach (p = 0.005). There were no significant differences between the lateral and posterior approaches (p = 0.06) and between the DAA and the posterior approaches (p = 0.11). In total, the mean pain level was 0.4 ± 0.9 (0-5) at 6 weeks and 0.5 ± 1.1 (0-7) at 2 years postoperatively (p = 0.3). Regarding the different approach groups, pain levels 6 weeks and 2 years postoperatively were significantly lower for the DAA than for the lateral approach (p = 0.02). There were no significant differences between DAA and posterior approach (p = 0.05) and the lateral and posterior approach (p = 0.26). The mean mHHS significantly increased from 84.7 + 14.5 (37.4-100) 6 weeks to 95 + 12.5 (23.1-100.1) 2 years postoperatively (p < 0.0001). Regarding the different approaches, mHHS was significantly higher for the DAA than for the lateral approach (p = 0.03). Differences between the DAA and the posterior approach (p = 0.11) and between the lateral and posterior approaches (p = 0.24) were insignificant. CONCLUSION: At 2 years postoperative, DAA showed significantly better overall satisfaction, pain level, and mHHS than the lateral approach. The differences between DAA and the posterior approach and lateral and posterior approaches were insignificant. Whether the superior results of the DAA to the lateral approach persist over a longer period must be clarified by further studies. STUDY DESIGN: Prospective cohort study, level of evidence 2.

Guideline for schizophrenia: implementation status and attitude toward an upcoming living guideline.

The implementation status of clinical guidelines is, despite their important role in connecting research with practice, frequently not satisfactory. This study aims to investigate the implementation status of the current German guideline for schizophrenia. Moreover, the attitude toward a living guideline has been explored for the first time by presenting screenshots of the German schizophrenia guideline transferred to a digital living guideline format called MAGICapp. A cross-sectional online survey was performed under the participation of 17 hospitals for psychiatry and psychosomatic medicine in Southern Germany and one professional association for German neurologists and psychiatrists. 439 participants supplied sufficient data for analysis. 309 provided complete data sets. Regarding the current guideline for schizophrenia and key recommendations, a large awareness-to-adherence gap was found. Group comparisons between different professions (caregivers, medical doctors, psychologists/psychotherapists, psychosocial therapists) detected differences in the implementation status showing higher awareness and agreement with the schizophrenia guideline and its key recommendations among medical doctors compared to psychosocial therapists and caregivers. Moreover, we detected differences in the implementation status of the guideline as a whole and its key recommendations between specialist and assistant doctors. The attitude toward an upcoming living guideline was mostly positive, especially among younger healthcare professionals. Our findings confirm an awareness-to-adherence gap, not only for the current schizophrenia guideline in general but also for its key recommendations with apparent differences between professions. Overall, our results show promising positive attitudes toward the living guideline for schizophrenia among healthcare providers, suggesting that a living guideline may be a supportive tool in everyday clinical practice.

Management of Irreparable Posterosuperior Rotator Cuff Tears-A Current Concepts Review and Proposed Treatment Algorithm by the AGA Shoulder Committee.

Posterosuperior rotator cuff tears range among the most common causes of shoulder complaints. While non-operative treatment is typically reserved for the elderly patient with low functional demands, surgical treatment is considered the gold standard for active patients. More precisely, an anatomic rotator cuff repair (RCR) is considered the most desirable treatment option and should be generally attempted during surgery. If an anatomic RCR is impossible, the adequate choice of treatment for irreparable rotator cuff tears remains a matter of debate among shoulder surgeons. Following a critical review of the contemporary literature, the authors suggest the following evidence- and experience-based treatment recommendation. In the non-functional, osteoarthritic shoulder, treatment strategies in the management of irreparable posterosuperior RCT include debridement-based procedures and reverse total shoulder arthroplasty as the treatment of choice. Joint-preserving procedures aimed at restoring glenohumeral biomechanics and function should be reserved for the non-osteoarthritic shoulder. Prior to these procedures, however, patients should be counseled about deteriorating results over time. Recent innovations such as the superior capsule reconstruction and the implantation of a subacromial spacer show promising short-term results, yet future studies with long-term follow-up are required to derive stronger recommendations.

Assessment of reporting practices and reproducibility potential of a cohort of published studies in computational knee biomechanics.

Reproducible research serves as a pillar of the scientific method and is a foundation for scientific advancement. However, estimates for irreproducibility of preclinical science range from 75% to 90%. The importance of reproducible science has not been assessed in the context of mechanics-based modeling of human joints such as the knee, despite this being an area that has seen dramatic growth. Framed in the context of five experienced teams currently documenting knee modeling procedures, the aim of this study was to evaluate reporting and the perceived potential for reproducibility across studies the teams viewed as important contributions to the literature. A cohort of studies was selected by polling, which resulted in an assessment of nine studies as opposed to a broader analysis across the literature. Using a published checklist for reporting of modeling features, the cohort was evaluated for both "reporting" and their potential to be "reproduced," which was delineated into six major modeling categories and three subcategories. Logistic regression analysis revealed that for individual modeling categories, the proportion of "reported" occurrences ranged from 0.31, 95% confidence interval (CI) [0.23, 0.41] to 0.77, 95% CI: [0.68, 0.86]. The proportion of whether a category was perceived as "reproducible" ranged from 0.22, 95% CI: [0.15, 0.31] to 0.44, 95% CI: [0.35, 0.55]. The relatively low ratios highlight an opportunity to improve reporting and reproducibility of knee modeling studies. Ongoing efforts, including our findings, contribute to a dialogue that facilitates adoption of practices that provide both credibility and translation possibilities.

Structured implementation of digital, systematically updated guideline recommendations for enhanced adherence in schizophrenia (SISYPHOS)-protocol of a cluster-randomized trial.

BACKGROUND: Despite high acceptance rates in the field, the implementation of the 2019 published German evidence and consensus-based S3 guideline is unsatisfactory. This study aims to assess the superiority of an adaptive online version with a better visualization of the recommendations in terms of guideline conformity, application of shared decision making, and digital health expertise compared to the classic pdf print version of the guideline. METHODS: The study is a multicenter, controlled, cluster-randomized trial with two arms: one arm investigating the implementation of the German schizophrenia guideline in form of a digital format (intervention group using the evidence ecosystem MAGICapp), the other arm in form of the classic print pdf version (control group). Physicians and psychologists working in specialized hospitals will be included in the study. The guideline-knowledge before and after the intervention is defined as primary outcome measure. Secondary endpoints include digital health expertise and application of shared decision making. DISCUSSION: This is the first study evaluating if an adaptive-digital version of the schizophrenia guideline is superior to the classic pdf print version. Therefore, the guideline is digitally prepared in the evidence-ecosystem MAGICapp, which covers the whole process of the development of a living guideline. We intend to use the results of the cluster-randomized trial for developing the German S3 guideline for schizophrenia in form of a living guideline in future. TRIAL REGISTRATION: The study is registered (10 May 2022) in the German Clinical Trials Register (DRKS) and the WHO International Clinical Trials Registry Platform (ICTRP) under registration number DRKS00028895 .

The effect of different grasping types on strain distributions in the trapezium of bonobos (Pan paniscus).

The thumb has played a key role in primate evolution due to its involvement in grasping and manipulation. A large component of this wide functionality is by virtue of the uniquely shaped trapeziometacarpal (TMC) joint. This TMC joint allows for a broad range of functional positions, but how its bone structure is adapted to withstand such a large variety of loading regimes is poorly understood. Here, we outline a novel, integrated finite element - micro finite element (FE-µFE) workflow to analyse strain distributions across the internal bony architecture. We have applied this modelling approach to study functional adaptation in the bonobo thumb. More specifically, the approach allows us to evaluate how strain is distributed through the trapezium upon loading of its distal articular facet. As loading conditions, we use pressure distributions for different types of grasping that were estimated in a previous study. Model evaluation shows that the simulated strain values fall within realistic boundaries of the mechanical response of bone. The results show that the strain distributions between the simulated grasps are highly similar, with dissipation towards the proximo-ulnar cluster of trabeculae regardless of trapezial bone architecture. This study presents an innovative FE-µFE approach to simulating strain distributions, and yields insight in the functional adaptation of the TMC joint in bonobos.

From conventional to living guidelines - faster updates for better informed guidance? A scoping review.

OBJECTIVE: The goal of living guidelines is keeping recommendations in guidelines up-to-date as new evidence becomes available. This review aims at scoping the prevalence and formal characteristics of living guidelines in the field of medicine and explore differences between formats. METHODS: A selective search of living guidelines in MEDLINE via PubMed, Google Scholar and six relevant online repositories for guidelines (MAGICApp, AWMF, GIN, NICE, WHO-Iris, BIGG) was conducted. Authors and editors were contacted to receive previous non-living guideline versions. Living guidelines were subsequently analyzed according to pre-defined methodological criteria as described below (inter-comparison). Differences between living and their conventional (non-living) versions were assessed (intra-comparison). RESULTS: 83 living guidelines were identified and selected for further screening, out of which 26 were eligible for analysis. 61.5% were new publications (de-novo guidelines) and 38.5% updates of pre-existing guidelines. There are some concepts defining, for example, the update cycle (AWMF, maximum of 12 months) but not all living guidelines follow or refer to existing concepts. The analysis shows that living guidelines in line with the established standards for (non-living) clinical guidelines involve an evidence standard, an extensive consensus process (often in the form of a Delphi process), and the inclusion of stakeholders (patients/relatives) in the development process, despite the high frequency of updates. When comparing living and conventional guidelines with the descriptive approach changes were found in update frequency (being more frequent with living guidelines, annually at the latest) and publication format (towards more digital) and public consultation (living guidelines offered more possibilities), no substantial methodological differences were observed in the description of consensus processes, changes in number of recommendations, inclusion of patient representatives. Given the small number of comparable pairs, the results reflect a tendency in the analyzed sample. CONCLUSIONS: The definition and development of living guidelines varied. Standardization (i. e. in the form of a checklist, procedure template) is needed to assess quality of the living process.

Cartilage thickness and bone shape variations as a function of sex, height, body mass, and age in young adult knees.

The functional relationship between bone and cartilage is modulated by mechanical factors. Scarce data exist on the relationship between bone shape and the spatial distribution of cartilage thickness. The aim of the study was to characterise the coupled variation in knee bone morphology and cartilage thickness distributions in knees with healthy cartilage and investigate this relationship as a function of sex, height, body mass, and age. MR images of 51 knees from young adults (28.4 ± 4.1 years) were obtained from a previous study and used to train a statistical shape model of the femur, tibia, and patella and their cartilages. Five multiple linear regression models were fitted to characterise morphology as a function of sex, height, body mass, and age. A logistic regression classifier was fitted to characterise morphological differences between males and females, and tenfold cross-validation was performed to evaluate the models' performance. Our results showed that cartilage thickness and its distribution were coupled to bone morphology. The first five shape modes captured over 90% of the variance and described coupled changes to the bone and spatial distribution of cartilage thickness. Mode 1 (size) was correlated to sex (p < 0.001) and height (p < 0.0001). Mode 2 (aspect ratio) was also correlated to sex (p = 0.006) and height (p = 0.017). Mode 4 (condylar depth) was correlated to sex only (p = 0.024). A logistic regression model trained on modes 1, 2, and 4 could classify sex with an accuracy of 92.2% (95% CI [81.1%, 97.8%]). No other modes were influenced by sex, height, body mass, or age. This study demonstrated the coupled relationship between bone and cartilage, showing that cartilage is thicker with increased bone size, diaphysis size, and decreased femoral skew. Our results show that sex and height influence bone shape and the spatial distribution of cartilage thickness in a healthy young adult population, but body mass and age do not.

O arco teleológico da ética da desinformação: dos pomadistas de Machado de Assis aos negacionistas da pandemia / The teleological arc of disinformation ethics: from the pomadistas of Machado de Assis to the deniers of the pandemic / El arco teleológico de la ética de la desinformación: de los pomadistas de Machado de Assis a los negacionistas de la pandemia

O artigo analisa distintas finalidades de práticas desinformacionais, notadamente no campo da saúde pública. O método contempla análise bibliográfica comparada multidisciplinar nas dobras da filosofia e da ciência da informação, tendo como principais objetos de investigação um documento literário de Machado de Assis, de 1822, e um documento governamental da Comissão Parlamentar de Inquérito da Pandemia, de 2021. O intuito é comparar a ética que orienta as ações ficcionais dos charlatões do conto machadiano (os "pomadistas") e as práticas de desinformação em saúde apontadas pela CPI em pauta. O resultado da análise revela a amplitude do fenômeno da desinformação e seus resultados, em um arco que pode se estender da proteção à vida até a condução à morte. Conclui-se que a desinformação precisa ser discutida com responsabilidade para evitar representações irrefletidas ou moralistas, e os estudos baseados na ética da informação podem contribuir para o aprofundamento filosófico e a avaliação crítica do fenômeno.

The article analyzes different purposes of disinformation practices, notably in the field of public health. The method includes a multidisciplinary comparative bibliographic analysis, in the interface of philosophy and information science, having as main objects of investigation a literary document by Machado de Assis, published in 1822, and a government document made available for the public by the Parliamentary Commission of Inquiry on the Pandemic, in 2021. The aim is to compare the ethics that guide the fictional actions of the charlatans of the Machadian tale (the "pomadistas") and the practices of disinformation in public health, as pointed out by the CPI. The result of the analysis reveals the scope of the phenomenon of disinformation and its results, in an arc that can go from the life protection until driving to death. It is concluded that disinformation needs to be discussed responsibly to avoid thoughtless or moralistic representations, and the studies based on information ethics can contribute to the philosophical deepening and critical evaluation of the phenomenon.

El artículo analiza diferentes propósitos de las prácticas de desinformación, especialmente en el campo de la salud pública. El método incluye un análisis bibliográfico comparativo multidisciplinario, en la interfaz de la filosofía y las ciencias de la información, teniendo como principales objetos de investigación un documento literario de Machado de Assis, de 1822, y un documento gubernamental de la Comisión Parlamentaria de Investigación sobre la Pandemia, de 2021. El objetivo es comparar la ética que guía la acción ficcional de los charlatanes del cuento de Machado de Assis (los "pomadistas") y las prácticas de desinformación en salud, señaladas por la CPI. El resultado del análisis revela la amplitud del fenómeno de la desinformación y sus resultados, en un arco que puede ir desde la protección a la vida hasta la conducción a la muerte. Se concluye que la desinformación necesita ser discutida con responsabilidad para evitar representaciones irreflexivas o moralistas, y los estudios basados en la ética de la información pueden contribuir para la profundización filosófica y la evaluación crítica del fenómeno.

A Parameter Sensitivity Analysis on Multiple Finite Element Knee Joint Models.

The reproducibility of computational knee joint modeling is questionable, with models varying depending on the modeling team. The influence of model variations on simulation outcomes should be investigated, since knowing the sensitivity of the model outcomes to model parameters could help determine which parameters to calibrate and which parameters could potentially be standardized, improving model reproducibility. Previous sensitivity analyses on finite element knee joint models have typically used one model, with a few parameters and ligaments represented as line segments. In this study, a parameter sensitivity analysis was performed using multiple finite element knee joint models with continuum ligament representations. Four previously developed and calibrated models of the tibiofemoral joint were used. Parameters of the ligament and meniscus material models, the cartilage contact formulation, the simulation control and the rigid cylindrical joints were studied. Varus-valgus simulations were performed, changing one parameter at a time. The sensitivity on model convergence, valgus kinematics, articulating cartilage contact pressure and contact pressure location were investigated. A scoring system was defined to categorize the parameters as having a "large," "medium" or "small" influence on model output. Model outcomes were sensitive to the ligament prestretch factor, Young's modulus and attachment condition parameters. Changes in the meniscus horn stiffness had a "small" influence. Of the cartilage contact parameters, the penalty factor and Augmented Lagrangian setting had a "large" influence on the cartilage contact pressure. In the rigid cylindrical joint, the largest influence on the outcome parameters was found by the moment penalty parameter, which caused convergence issues. The force penalty and gap tolerance had a "small" influence at most. For the majority of parameters, the sensitivity was model-dependent. For example, only two models showed convergence issues when changing the Quasi-Newton update method. Due to the sensitivity of the model parameters being model-specific, the sensitivity of the parameters found in one model cannot be assumed to be the same in other models. The sensitivity of the model outcomes to ligament material properties confirms that calibration of these parameters is critical and using literature values may not be appropriate.