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Arthroplasty Today Jun 2019Dynamic tibial tray sensors are playing an increasing role in total knee arthroplasty (TKA) coronal balancing. Sensor balance is proposed to lead to improved patient...
BACKGROUND
Dynamic tibial tray sensors are playing an increasing role in total knee arthroplasty (TKA) coronal balancing. Sensor balance is proposed to lead to improved patient outcomes compared with sensor-unbalanced TKA, and traditional manual-balanced TKA. However, the "learning curve" of this technology is not known, and also whether sensor use can improve manual TKA balance skills once the sensor is taken away, effectively "training" the surgeon.
METHODS
We conducted a single-surgeon prospective study on 104 consecutive TKAs. In Nonblinded Phase I (n = 49), sensor-directed releases were performed during trialing and final intercompartmental load was recorded. In Blinded Phase II (n = 55), manual-balanced TKA was performed and final sensor readings were recorded by a blinded observer after cementation. We used cumulative summation analysis and sequential probability ratio testing to analyze the surgeon learning curve in both phases.
RESULTS
In Nonblinded Phase I, sensor balance proficiency was attained most easily at 10°, followed by 90°, and most difficult to attain at 45° of flexion. In Blinded Phase II, manual balance was lost most quickly at 45°, followed by 90°, and preserved for longest at 10° of flexion. The number of cases in the steady state periods (early phase periods where there is a mix of sensor balance and sensor imbalance) for both phases is similar.
CONCLUSIONS
A surgeon who consistently uses the dynamic sensor demonstrates a learning curve with its use, and an "attrition" curve once it is removed. Consistent sensor balance is more predictable with constant sensor use.
PubMed: 31286045
DOI: 10.1016/j.artd.2019.03.001 -
Cureus Feb 2024Introduction The concept of work-life balance is a complex, multidimensional intertwinement of the roles an individual plays in their professional and personal life....
Introduction The concept of work-life balance is a complex, multidimensional intertwinement of the roles an individual plays in their professional and personal life. Work-life balance is crucial for every profession, and doctors have no exemption not exempted from it. Medical students and young graduates face numerous challenges that potentially impact their work (study)-life balance. Objectives of the study The aim is to assess the hours spent in study and the hours spent in non-study activities by medical students and graduates in India and to assess the study-life balance among them. Methodology A cross-sectional observational study employing a predefined web-basedsurvey to investigate the study-life balance among medical students and graduates across India. A predesigned questionnaire was designed and made accessible through Google Forms, which was distributed among doctors across India via popular social media platforms. Data management was conducted using Microsoft Excel and Data analysis was done using SPSS (IBM Corp., Armonk, NY). Results A total of 416 responses were included in the study. The study participants were predominantly female (64.2%). Most of the study participants were from the State of Telangana (63.9%). The time spent studying was < 10 hours/week for 43.8% students and 10-25 hours/week for 27.2% students. Around 24% students reported spending 10-25 hours/week in hospital. While 47.4% reported spending less than one to two hours per day with their family, 26% of the participants answered "yes" to the question "Do you feel that your study-life is stressful?." Conclusions Self-care and study-life balance is a multi-factorial focal area that is based on balancing stress and happiness, with completing the tasks of the medical school. Medical students need to receive proper guidelines to transition into medical school for better study-life balance.
PubMed: 38558639
DOI: 10.7759/cureus.55293 -
The Journal of Arthroplasty Jun 2023Instability is a leading cause of early failure following total knee arthroplasty (TKA). Enabling technologies can improve accuracy, but their clinical value remains...
BACKGROUND
Instability is a leading cause of early failure following total knee arthroplasty (TKA). Enabling technologies can improve accuracy, but their clinical value remains undetermined. The purpose of this study was to determine the value of achieving a balanced knee joint at the time of TKA.
METHODS
A Markov model was developed to determine the value from reduced revisions and improved outcomes associated with TKA joint balance. Patients were modeled for the first 5 years following TKA. The threshold to determine cost-effectiveness was set at an incremental cost effectiveness ratio of $50,000/quality-adjusted life year (QALY). A sensitivity analysis was performed to evaluate the influence of QALY improvement (ΔQALY) and Revision Rate Reduction on additional value generated compared to a conventional TKA cohort. The impact of each variable was evaluated by iterating over a range of ΔQALY (0 to 0.046) and Revision Rate Reduction (0% to 30%) and calculating the value generated while satisfying the incremental cost effectiveness ratio threshold. Finally, the impact of surgeon volume on these outcomes was analyzed.
RESULTS
The total value of a balanced knee for the first 5 years was $8,750, $6,575, and $4,417 per case, for low, medium, and high-volume surgeons, respectively. Change in QALY accounted for greater than 90% of the value gain with a reduction in revisions making up the rest in all scenarios. The economic contribution of revision reduction was relatively constant regardless of surgeon volume ($500/case).
CONCLUSION
Achieving a balanced knee had the greatest impact on ΔQALY over early revision rate. These results can help assign value to enabling technologies with joint balancing capabilities.
Topics: Humans; Arthroplasty, Replacement, Knee; Knee Joint; Cost-Benefit Analysis; Osteoarthritis, Knee; Reoperation
PubMed: 36933683
DOI: 10.1016/j.arth.2023.03.022 -
Progress in Brain Research 2019Social behavioral disturbances are central to most psychiatric disorders. A disequilibrium within the cortical excitatory and inhibitory neurotransmitter systems... (Review)
Review
Social behavioral disturbances are central to most psychiatric disorders. A disequilibrium within the cortical excitatory and inhibitory neurotransmitter systems underlies these deficits. Gamma-aminobutyric acid (GABA) and glutamate are the most abundant excitatory and inhibitory neurotransmitters in the brain that contribute to this equilibrium. Several contemporary therapies used in treating psychiatric disorders, regulate this GABA-glutamate balance. Yoga has been studied as an adjuvant treatment across a broad range of psychiatric disorders and is shown to have short-term therapeutic gains. Emerging evidence from recent clinical in vivo experiments suggests that yoga improves GABA-mediated cortical-inhibitory tone and enhances peripheral oxytocin levels. This is likely to have a more controlled downstream response of the hypothalamo-pituitary-adrenal system by means of reduced cortisol release and hence a blunted sympathetic response to stress. Animal and early fetal developmental studies suggest an inter-dependent role of oxytocin and GABA in regulating social behaviors. In keeping with these observations, we propose an integrated neurobiological model to study the mechanisms of therapeutic benefits with yoga. Apart from providing a neuroscientific basis for applying a traditional system of practice in the clinical setting, this model can be used as a framework for studying yoga mechanisms in future clinical trials.
Topics: Brain; Humans; Mental Disorders; Models, Biological; Neurotransmitter Agents; Yoga
PubMed: 30732846
DOI: 10.1016/bs.pbr.2018.10.024 -
Statistics in Medicine Oct 2020There are two seemingly unrelated approaches to weighting in observational studies. One of them maximizes the fit of a model for treatment assignment to then derive... (Review)
Review
There are two seemingly unrelated approaches to weighting in observational studies. One of them maximizes the fit of a model for treatment assignment to then derive weights-we call this the modeling approach. The other directly optimizes certain features of the weights-we call this the balancing approach. The implementations of these two approaches are related: the balancing approach implicitly models the propensity score, while instances of the modeling approach impose balance conditions on the covariates used to estimate the propensity score. In this article, we review and compare these two approaches to weighting. Previous review papers have focused on the modeling approach, emphasizing the importance of checking covariate balance. However, as we discuss, the dispersion of the weights is another important aspect of the weights to consider, in addition to the representativeness of the weighted sample and the sample boundedness of the weighted estimator. In particular, the dispersion of the weights is important because it translates into a measure of effective sample size, which can be used to select between alternative weighting schemes. In this article, we examine the balancing approach to weighting, discuss recent methodological developments, and compare instances of the balancing and modeling approaches in a simulation study and an empirical study. In practice, unless the treatment assignment model is known, we recommend using the balancing approach to weighting, as it systematically results in better covariate balance with weights that are minimally dispersed. As a result, effect estimates tend to be more accurate and stable.
Topics: Computer Simulation; Humans; Propensity Score
PubMed: 32882755
DOI: 10.1002/sim.8659 -
Current Opinion in Genetics &... Dec 2014Most human polymorphisms are neutral or slightly deleterious, but some genetic variation is advantageous and maintained in populations by balancing selection. Considered... (Review)
Review
Most human polymorphisms are neutral or slightly deleterious, but some genetic variation is advantageous and maintained in populations by balancing selection. Considered a rarity and overlooked for years, balanced polymorphisms have recently received renewed attention with several lines of evidence showing their relevance in human evolution. From theoretical work on its role in adaptation to empirical studies that identify its targets, recent developments have showed that balancing selection is more prevalent than previously thought. Here we review these developments and discuss their implications in our understanding of the influence of balancing selection in human evolution. We also review existing evidence on the biological functions that benefit most from advantageous diversity, and the functional consequences of these variants. Overall, we argue that balancing selection must be considered an important selective force in human evolution.
Topics: Adaptation, Physiological; Evolution, Molecular; Genetic Fitness; Genetic Variation; Humans; Models, Genetic; Polymorphism, Genetic; Selection, Genetic
PubMed: 25173959
DOI: 10.1016/j.gde.2014.08.001 -
Chaos (Woodbury, N.Y.) Oct 2018It is widely appreciated that balanced excitation and inhibition are necessary for proper function in neural networks. However, in principle, balance could be achieved...
It is widely appreciated that balanced excitation and inhibition are necessary for proper function in neural networks. However, in principle, balance could be achieved by many possible configurations of excitatory and inhibitory synaptic strengths and relative numbers of excitatory and inhibitory neurons. For instance, a given level of excitation could be balanced by either numerous inhibitory neurons with weak synapses or a few inhibitory neurons with strong synapses. Among the continuum of different but balanced configurations, why should any particular configuration be favored? Here, we address this question in the context of the entropy of network dynamics by studying an analytically tractable network of binary neurons. We find that entropy is highest at the boundary between excitation-dominant and inhibition-dominant regimes. Entropy also varies along this boundary with a trade-off between high and robust entropy: weak synapse strengths yield high network entropy which is fragile to parameter variations, while strong synapse strengths yield a lower, but more robust, network entropy. In the case where inhibitory and excitatory synapses are constrained to have similar strength, we find that a small, but non-zero fraction of inhibitory neurons, like that seen in mammalian cortex, results in robust and relatively high entropy.
PubMed: 30384653
DOI: 10.1063/1.5043429 -
Australian Occupational Therapy Journal Oct 2019Balancing Everyday Life (BEL) is a new lifestyle intervention for mental health services users, developed to support meaningful engagement in daily activities and a...
INTRODUCTION
Balancing Everyday Life (BEL) is a new lifestyle intervention for mental health services users, developed to support meaningful engagement in daily activities and a balanced lifestyle. This study aimed at exploring the BEL participants' process of making lifestyle changes.
METHODS
This constructivist grounded theory study took place in Sweden from 2013-2017 and explored the processes of 19 BEL participants when making lifestyle changes. Data were collected through 29 interviews.
RESULTS
A process of breaking a cycle of perceived failure and making changes toward a more balanced lifestyle was constructed, consisting of five categories: Going at it gently: change is an on-going process; Support for progress, permission to fail; Prioritising and setting boundaries; Adjusting for a sustainable balance; and Caring for a valued self. Each category included a strategy for change as well as a related inner change. Strategies involved learning and trying techniques for making changes toward a more balanced lifestyle, whereas the personal changes often involved a more self-compassionate approach and allowing oneself to utilise these techniques.
CONCLUSION
The results contribute to knowledge in the process of making lifestyle changes, specifically, how strategies for change and inner changes interact and can support personal recovery toward mental health. This knowledge could help to support clients in making personally meaningful changes toward a more balanced lifestyle as well as inform future research in the process of making change.
Topics: Adult; Aged; Female; Grounded Theory; Health Promotion; Humans; Interviews as Topic; Life Style; Male; Mental Health Services; Middle Aged; Occupational Therapy; Qualitative Research
PubMed: 31344759
DOI: 10.1111/1440-1630.12604 -
The Journal of Knee Surgery Feb 2019Despite the overall successful outcomes following primary total knee arthroplasty (TKA) and the concept that a well-balanced TKA yields a more successful result,...
Despite the overall successful outcomes following primary total knee arthroplasty (TKA) and the concept that a well-balanced TKA yields a more successful result, concerns still remain in the reported literature regarding the patellofemoral joint. Diminished outcomes have been associated with poorly balanced or placed patella implants. The effect of different techniques to achieve flexion-extension balance and the use of posterior stabilized (PS) versus cruciate retaining (CR) implant designs on patellofemoral balancing has not been previously studied. The purpose of this study is to utilize a validated computational analysis software to simulate the effects of varying implant positions and sizes of femoral components. The patellofemoral retinaculum (PFR) load was significantly affected by some conditions, while others did not reach significance. The proximal-distal implant position with knee flexion angle ( < 0.001), the implant size ( < 0.001), and the implant bearing type (CR/PS) ( < 0.05) were significant. For the proximal-distal implant position and knee flexion angle, a more proximal implant position (elevating the joint line) increased the PFR load from 15 to 30°, and a more proximal implant position reduced retinaculum load from 60 to 135°. However, at 45°, implant position does not affect retinaculum load. Achieving the appropriate balance between the dynamic nature of both the tibiofemoral and the patellofemoral interaction in TKA has proven to be complex and challenging to manage. Balancing of a TKA is essential to the proper functioning and overall longevity of the implant. These results demonstrate that patellofemoral balance is affected by implant size and position during flexion-extension gap balancing.
Topics: Aged; Arthroplasty, Replacement, Knee; Computer Simulation; Female; Humans; Knee Prosthesis; Male; Patellofemoral Joint; Prosthesis Design; Prosthesis Fitting
PubMed: 29514364
DOI: 10.1055/s-0038-1635112 -
Physics in Medicine and Biology Feb 2024Primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM) are malignant primary brain tumors with different biological characteristics. Great differences...
Primary central nervous system lymphoma (PCNSL) and glioblastoma (GBM) are malignant primary brain tumors with different biological characteristics. Great differences exist between the treatment strategies of PCNSL and GBM. Thus, accurately distinguishing between PCNSL and GBM before surgery is very important for guiding neurosurgery. At present, the spinal fluid of patients is commonly extracted to find tumor markers for diagnosis. However, this method not only causes secondary injury to patients, but also easily delays treatment. Although diagnosis using radiology images is non-invasive, the morphological features and texture features of the two in magnetic resonance imaging (MRI) are quite similar, making distinction with human eyes and image diagnosis very difficult. In order to solve the problem of insufficient number of samples and sample imbalance, we used data augmentation and balanced sample sampling methods. Conventional Transformer networks use patch segmentation operations to divide images into small patches, but the lack of communication between patches leads to unbalanced data layers.To address this problem, we propose a balanced patch embedding approach that extracts high-level semantic information by reducing the feature dimensionality and maintaining the geometric variation invariance of the features. This approach balances the interactions between the information and improves the representativeness of the data. To further address the imbalance problem, the balanced patch partition method is proposed to increase the receptive field by sampling the four corners of the sliding window and introducing a linear encoding component without increasing the computational effort, and designed a new balanced loss function.Benefiting from the overall balance design, we conducted an experiment using Balanced Transformer and obtained an accuracy of 99.89%, sensitivity of 99.74%, specificity of 99.73% and AUC of 99.19%, which is far higher than the previous results (accuracy of 89.6% ∼ 96.8%, sensitivity of 74.3% ∼ 91.3%, specificity of 88.9% ∼ 96.02% and AUC of 87.8% ∼ 94.9%).This study can accurately distinguish PCNSL and GBM before surgery. Because GBM is a common type of malignant tumor, the 1% improvement in accuracy has saved many patients and reduced treatment times considerably. Thus, it can provide doctors with a good basis for auxiliary diagnosis.
Topics: Humans; Glioblastoma; Diagnosis, Differential; Lymphoma; Brain Neoplasms; Magnetic Resonance Imaging; Central Nervous System; Central Nervous System Neoplasms
PubMed: 38232389
DOI: 10.1088/1361-6560/ad1f88