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Asymmetry in bilateral scapulothoracic motion and scapular dyskinesis
No full textAbstract
Scapular Dyskinesis (SD) refers to improper movement of the scapulothoracic (ST) joint, manifesting secondary to or causative of pathology. Scapular dyskinesis is clinically assessed/categorized based on observational asymmetries of scapular segmental prominence and ST upward rotation (UR), internal/external rotation (IER) and anterior/posterior tilt (APT). Bilateral ST motion symmetry is assumed in healthy individuals. The diagnostic distinction between non-pathological and pathological asymmetry for SD has not been elucidated. This experimental study assesses bilateral ST 3D-motion using simultaneously a laboratory camera-based validated passive reflective marker methodology (acromion marker clusters – AMC) and a non-invasive portable/clinically-feasible technology (inertia measurement units – IMU). The IMU derived 3D ST motion and asymmetry will be validated against the AMC system over six (6) bilateral simple arm elevation and compound tasks. Our experimental protocol is in progress with 7 of 15 right-handed, male, healthy subjects enrolled. Assessment of bilateral ST asymmetry has been reported as related to arm dominance, healthy-overhead athletes, and sex, with the latter two lacking sufficient consistency for comparison across studies. Specific to arm dominance, average bilateral ST motion differences across all planes of arm elevation are 2.95°, 1.39° and –1.92° for UR, APT and IER, respectively. These differences were observed on average dominant and non-dominant ST: UR of 34.2° and 32.65°, APT of 11.56° and 10.06°, and IER of 4.17° and 3.08°, respectively. The literature and our experimental data will be used to validate the IMU accuracy for the clinical setting and to determine acceptable ranges for non-pathological baselines for 3D ST motion and asymmetry
Medicaid expansions and private insurance “crowd-out” (1999–2019)
No full textBackground: Recent Medicaid expansions have rekindled the debate around private insurance “crowd-out.” Prior research is limited by short-time horizons and state-specific analyses. Our study overcomes these limitations by evaluating 20 years of Medicaid expansions across the entire United States. Methods: We obtain data from the U.S. Census Bureau for all U.S. states and District of Columbia for private insurance coverage rates of adults 18–64 for years 1999–2019. After estimating a naïve, staggered Two-way fixed effects difference-in-differences regression model, we implement four novel econometric methods to diagnose and overcome threats of bias from staggered designs. We also test for pre-treatment differential trends and heterogenous effects over time. Results: Our findings suggest that Medicaid expansion was associated with a 1.5 percent-point decline in private insurance rates (p \u3c 0.001). We also observe significant heterogeneity over time, with estimates peaking 4 years after expansion. Conclusions: Medicaid expansions reduced private insurance rates. Future research should assess whether or how this crowd-out may have affected consumer welfare or government budgets. Recognizing the crowd-out should enable policymakers to make informed decisions regarding healthcare policy. The importance of a 1-2 percent-point crowd-out, we leave for future research and debate
Synthesizing 30-years of adult medicaid dental policy research: A scoping review to identify gaps and opportunities
No full textObjective: Despite the importance of Medicaid for the oral health of low-income adults, the extent to which Medicaid dental policy variation influences outcomes is unknown. This study aims to review the evidence evaluating adult Medicaid dental policies to synthesize conclusions and motivate future research. Data sources: A comprehensive search of academic literature published in English between 1991 and 2020 was conducted to identify studies which evaluated an adult Medicaid dental policy for its effect on outcomes. Studies strictly involving children, policies not related to adult Medicaid dental coverage, and non-evaluation studies were excluded. The data analysis identified the policies, outcomes, methods, populations, and conclusions of the included studies. Results: Among the 2731 unique articles extracted, 53 met the inclusion criteria. 36 studies evaluated the effect of expanding Medicaid dental coverage, which was found to consistently increase dental service visits (21 studies) and reduce unmet dental needs (4 studies). Provider density, reimbursement rates, and level of benefits appear to influence the effect of expanding Medicaid dental coverage. The evidence for changing Medicaid benefits and reimbursement rates were mixed for its impact on provider participation and emergency dental services. Few studies examined how adult Medicaid dental policies impact health outcomes. Conclusions: Most of the recent research has focused on evaluating the effect of expanding or reducing Medicaid dental coverage on dental service utilization. Future research investigating the impact of adult Medicaid dental policies on clinical, health, and wellness outcomes remains warranted. Clinical significance: Low-income adults are responsive to Medicaid dental policy changes and utilize more care with more generous coverage. Less is known about how these policies influence health
Examining the “Medicare Effect” on Distant-Stage Cancer Diagnoses by Site, Gender, and Rurality
No full textBackground: Compared to cancers detected early, distant stage cancers are associated with lower survival, diminished quality of life, and higher costs. Evidence suggests that greater access to comprehensive health insurance (i.e., Medicare) improved early detection. Yet, few studies have evaluated the effect of Medicare coverage across cancers or factors influencing healthcare use.
Methods: This study analyzed 35 years of population-based cancer registry data from the Surveillance Epidemiology and End Results program for eight common cancers: Oral, Digestive, Respiratory, Skin, Genital, Urinary, Endocrine, and Breast. Leveraging the subjective threshold determining Medicare’s eligibility at age 65, Medicare’s effect on the probability of a distant diagnosis was estimated using Robust Non-Parametric Regression Discontinuity models.
Results: Medicare was associated with reduced proportion of distant diagnoses for five common cancers. The proportion of distant cancers declined by 1.7-percentage points for digestive cancers (p \u3c 0.01), 1.6-percentage points for respiratory cancers (p \u3c 0.01), 0.5-percentage points for genital cancers (p \u3c 0.05), 1.4-percentage points for urinary cancers (p \u3c 0.01), and 0.8-percentage points for female breast cancers (p \u3c 0.01). The relative difference from average distant stage rates for these significant estimates range from 3% (Respiratory) to 15% (Genital). Most estimates were consistent across gender, but Medicare was only associated with declined distant-stage diagnoses for patients in urban and metro regions.
Conclusions: This study reaffirms that Medicare coverage is associated with earlier diagnoses for patients in urban and metro regions for digestive, respiratory, genital, urinary, and female breast cancers. These results stress the importance of healthcare insurance, but also reveal the limitations of insurance expansion policies for patients in rural areas and for cancers without standard screening protocols
The 2020 US cancer screening deficit and the timing of adults\u27 most recent screen: a population-based cross-sectional study
No full textObjective In 2020, cancer screenings declined, resulting in a cancer screening deficit. The significance of this deficit, however, has yet to be quantified from a population health perspective. Our study addresses this evidence gap by examining how the pandemic changed the timing of American adults\u27 most recent cancer screen. Methodology We obtained population-based, cancer screening data from the Behavioural Risk Factor Surveillance System (BRFSS) (2010, 2012, 2014, 2016, 2018, 2020). Mammograms, pap smears and colonoscopies were each specified as a variable of mutually exclusive categories to indicate the timing since the most recent screening (never, 0-1 years, 1-2 years, 3+ years). Our cross-sectional, quasi-experimental design restricts the sample to adults surveyed in January, February or March. We then leverage a quirk in the BRFSS implementation and consider adults surveyed in the second year of the 2020 survey wave as exposed to the COVID-19 pandemic. Respondents surveyed in January 2020-March 2020 were considered unexposed. To estimate the impact of exposure to the COVID-19 pandemic on the timing of recent cancer screenings, we constructed linear and logistic regression models which control for sociodemographic characteristics associated with screening patterns, and state fixed effects and temporal trend fixed effects to control for confounding. Results In 2020, the cancer screening deficit was largely due to a 1 year delay among adults who receive annual screening, as the proportion of adults reporting a cancer screen in the past year declined by a nearly identical proportion of adults reporting their most recent cancer screen 1-2 years ago (3%-4% points). However, the relative change was higher for mammograms and pap smears (17%) than colonoscopies (4%). We also found some evidence that the proportion of women reporting never having completed a mammogram declined in 2020, but the mechanisms for this finding should be further explored with the release of future data. Conclusion Our estimates for the pandemic\u27s effect on cancer screening rates are smaller than prior studies. Because we account for temporal trends, we believe prior studies overestimated the effect of the pandemic and underestimated the overall downward trend in cancer screenings across the country leading up to 2020
Estrogen influences voluntary wheel running behavior in female rats
No full textAbstract
Regular exercise is recognized for its mental and physical health benefits in contrast to the complex risks associated with a sedentary lifestyle. Although the physiological mechanisms underlying the positive effects of exercise are well-established, the factors influencing exercise behavior and the motivation to maintain regular physical activity remain largely unknown. Using a rodent model of voluntary wheel running (VWR), we investigated the role of estrogen in exercise behavior and its regulation. We found that female rats ran more than their male counterparts, and they displayed a unique rhythm in daily activity which directly mirrored the fluctuating estrogen levels throughout the estrous cycle. This rhythm was evident in the daily running distance, speed and running duration under normal physiological conditions. Ovariectomy (OVX) significantly reduced overall VWR activity and eliminated the rhythm. Subcutaneous injections of estradiol benzoate (EB) at 1.5 μg in an OVX background reliably revived overall VWR activity to similar levels before OVX. This estrogen replacement preserved individual differences, such that high vs. low runners before OVX remain high and low runners after treatment, indicating a causal link between estrogen and VWR activity. However, this EB-induced behavioral response took more than 24 hours to manifest, suggesting a temporal arrangement and activation of estrogen/estrogen receptor-mediated genomic signaling cascades with VWR responses. Investigating the molecular events prior to the behavioral manifestation provides a unique opportunity for identifying estrogen-dependent molecular mechanisms that drive running behavior. Understanding these mechanisms is critical for improved strategies to promote physical activity in humans
Break (snack)
No full textA quick break for the attendees in between poster presentations and oral presentations
Comparing CT scout and simulated radiographs on reliability of frontal sinus measurement
No full textAbstract
Uniqueness of frontal sinuses can be used as a distinguishing factor for post-mortem identification. Post-mortem studies must be reliably matched to previous antemortem imaging done on the individual, even if that imaging is from different machines. Thus, it is critical to be able to accurately relate CT scans and radiographs. To verify the repeatability of measuring the frontal sinus, dimensions between both imaging modalities and measurers were analyzed. In order to compare this, 3DSlicer was used to compile CT images from 15 individuals into simulated radiographs. Eight measurements were taken from these radiographs and compared to the measurements gathered from the scout images from each CT scan. A paired-t test was performed to compare intraobserver data, i.e., data collected by the same observer from the same images, interobserver data, i.e., data collected by two separate observers on the same images, and intermodality data, i.e., data collected by the same observer on images of the same individual in two different imaging modalities. Intraobserver data was not statistically different (p\u3e0.05). However, interobserver error showed differences between maximum breadth of the sinus (p=0.010) and a measure of left sinus breadth (p=0.04). Similarly, intermodality error showed a significant difference between maximum breadth (p=0.023) and a measure of right sinus breadth (p\u3c 0.001). These measurements likely differ because of a single outlier individual, but all other measurements were not significantly different. This shows reliability in certain measurements between imaging modalities, but there is a margin of error that may impact current post mortem identification
Finite Element Analysis (FEA) Reveals Increased Force Used by the Forelimbs in the Sabertoot Cat, Smilodon fatalis
No full textAbstract
The sabertooth cat, Smilodon fatalis, was a carnivorous predator that lived during the Ice Age, or Pleistocene Epoch 2.5 million to 11,000 years ago. Unlike modern cats that kill their prey with a suffocating bite to the windpipe, sabertooth cat teeth were too fragile for this method of prey-killing. Sabertooth cats were known to have muscular forelimbs to hold prey down before delivering a fatal bite to the neck viscera with their large saber canines. Morphological specimens were measured and analyzed using finite element analysis technology, an engineering technique that utilizes the material properties of solids to stimulate stress and strain in the material of interest. Bone tissue of the the humerus was used to compare the stress and strain potential of the sabertooth cat, S. fatalis, to living large cats.
We leveraged heterogeneous finite element (FE) models generated with species-specific material properties to assess the strength of S. fatalis’ forelimbs in prey-holding posture. Results indicate S. fatalis had the strongest overall forearm strength compared to pantherines, exceeding that of lion (P. leo), leopard (P. pardus), jaguar (P. onca), and was most similar to tiger (P. tigris). These findings are consistent with the inference that sabertooth evolution involved widespread modification and coordination of musculoskeletal performance in increasingly specialized forms
Diffusion Tensor Imaging of the Carnivora Brain: A Pilot Study
No full textAbstract
Fiber tractography is relatively novel method for reconstructing the course and location of white matter tracts in the mammalian brain. While this approach has been applied extensively in human studies, very few studies have looked at the application of this approach to the study of non-traditional animal models. Here we look to explore the use of fiber tractography to reconstruct the major commissural, association and projection fiber pathways in a range of closely related Carnivora. The null hypothesis is that fiber pathways in closely related species of carnivora have remained largely unchanged and are indicative of the constraints (architectural, developmental, or phylogenetic) that unite species within a given Order. Alternatively, deviations from this known bauplan are interpreted as species specific variation, which is directly related to the unique ecological context of each species (i.e., hunting strategies, social organization and or cognition)