Negative Variance Research Articles

Imaginary latent variables: Empirical testing for detecting deficiency in reflective measures

Imaginary latent variables are variables with negative variances and have been used to implement constraints in measurement models. This article aimed to advance this practice and rationalize the imaginary latent variables as a method to detect possible latent deficiencies in measurement models. This rationale is based on the theory of complex numbers used in the measurement process of common factor model–based structural equation modeling. Modeling an imaginary latent variable produces a potential deficiency within its relative reflective measures through a considerable reduction in common variance indicating the most affected indicator(s).

A Stepwise‐Clustered Precipitation Downscaling Method for Ensemble Climatic Projections in the Mediterranean Region

ABSTRACTPrecipitation changes dynamically in the Mediterranean region. Therefore, the projection of future precipitation and its historical distribution mechanism is essential for climate mitigation and adaptation. In this study, a stepwise clustered precipitation downscaling method (SCPD) was developed and adopted in the Mediterranean region to reveal the inherent variation rules and trends over the future 100 years under two SSP scenarios. A cutting and merging multivariate process is introduced to build a cluster tree for supporting further downscaling and projecting steps. The ensemble average from the global climate model (GCM) dataset is used for precipitation projections. The precipitation performance of SCPD, evaluated by R2, is fairly decent. The precipitation projections vary with the original rainfall patterns over the gauge stations. Dry places tend to become comparably drier in the future. Precipitation in the northern Mediterranean region shows a drier winter–spring and wetter summer–autumn. Opposite trends emerged in the southern part, with increasing winter precipitation and decreasing summer rainfall. The rising carbon dioxide concentration will further intensify the decrease in rainfall. However, the centres of these two EOFs are not identical. The contributions of NAO (positive) and Niño 3.4 (negative) to PC1 are relatively high. Accordingly, the strongest positive correlation with PC2 is SCAND, as well as negative correlations with AO, NAO and EAWR. Positive anomaly precipitation is attributed to PC1, whereas PC2 is responsible for most of the negative variance precipitation.

Non-negative least-squares variance and covariance component estimation using the positive-valued function for errors-in-variables models

Abstract Although (co)variance component estimation has been widely applied in the errors-in-variables (EIV) model, the occurrence of negative variance components is still a major issue in the estimated variance components. This problem may be due to the following unfavorable factors: 1) unreasonable selection of initial variance values; 2) low redundancy in the EIV functional model; 3) improper design in the EIV stochastic model, and 4) other data quality problems. Many attempts have been made to prevent the appearance of negative variance components. In this contribution, a novel and efficient non-negative least-squares variance component estimation using the PVF (PVF-NLS-VCE) is introduced, which can simultaneously estimate the unknown (co)variance components in the EIV stochastic model and the parameters in the EIV functional model. Its principle is to implicitly impose a non-negative constraint by replacing the variance component with the positive-valued function (PVF) whose range is the set of positive real numbers. Two numerical examples using real and simulated data are presented. The numerical results of linear regression are identical to those obtained based on least-squares variance component estimation (LS-VCE) with positive initial values of variance components. The numerical results of two-dimensional affine transformation are shown to prevent negative variance components and precede those obtained by LS-VCE with a negative initial value of variance component. Both numerical examples verify the effectiveness of the PVF-NLS-VCE method whether the initial values of variance components are positive or negative. The proposed PVF-NLS-VCE is a simple, convenient and flexible method to achieve the non-negative estimates of variance components, which can reduce sensitivity to initial value selection and automatically guarantee a non-negative definite covariance matrix.

Distal Radius Osteotomies for Kienbock's Disease—A Minimally Invasive Approach

Abstract Background Negative ulnar variance is a recognized predisposing factor for Kienbock's disease (KD). Radial shortening osteotomy (RSO) reduces radial height, thereby alleviating stress on the lunate. Conversely, radial closed wedge osteotomy (RCWO) involves removing a distal radius wedge to not only decrease radial height but also reduce radial inclination, thereby enhancing lunate coverage. Description This article outlines a straightforward and minimally invasive approach to RSO utilizing a single cut and stabilization with a single screw. Additionally, it introduces a technique for RCWO comprising two cuts, wedge removal from the distal radius, and fixation using a single headless screw. Literature Review Traditionally, RSO and RCWO procedures include a volar approach consistent with distal radius fracture fixation techniques. However, the reliance on “free-hand” cuts may necessitate larger hardware for stabilization. Overcorrection poses risks of suboptimal outcomes and often mandates subsequent hardware removal procedures. Clinical Relevance Both RSO and RCWO techniques offer minimally invasive solutions, which preserve the periosteum, and maintain stability. These techniques only require a single screw and a removable splint. RSO is indicated for KD wrists with negative ulnar variance, while RCWO is preferable for cases with negative ulnar variance and increased radial inclination.

Harnessing 3D seismic data for mapping natural CO2 distribution: Paving the way for future CCS/CCUS implementation in the Lower Talang Akar Formation, Jabung Block, South Sumatra Basin

Hydrocarbon reservoirs saturated with CO2 are naturally widespread in the Lower Talang Akar Formation (LTAF) and deposited in the Jabung Block, South Sumatra Basin, Indonesia. The different CO2 saturation contents stored in the reservoirs pose a challenge to planning future carbon capture and storage (CCS) and carbon capture, utilization, and storage (CCUS) in the area. This study integrates poststack 3D seismic data and existing wells in the western part of the Jabung Block. It utilizes seismic attribute methods such as sum of negative amplitude, relative impedance, variance, and ant tracking to predict the origin, saturation, and distribution of CO2-saturated hydrocarbon accumulations in the sandstone reservoirs of the LTAF. The results show that CO2 originated from the Betara Deep source rock in the study area's eastern side and migrated to the reservoirs through major northwest–southeast-trending fault zones. The saturation of CO2 in the reservoirs is mainly controlled by the distance from the source and the reservoir depths, faulting, and fracturing intensity. The fields closer to the Betara source rock tend to be filled with higher contents of CO2 saturation. The results provide valuable guidance in CO2 identification and mapping for future CCS and CCUS implementation in the study area.

Precipitation dynamics and its interactions with possible drivers over global highlands

The climate and ecosystem in the highland regions are fragile and vulnerable to climate change. This study used ERA5, CRU, and CHIRPS at 0.5° × 0.5° resolution to assess spatiotemporal precipitation trends over global highlands from 1981 to 2021. The Standardized anomaly index (SAI) is used to evaluate the comparative anomalies between the datasets, while the Mann-Kendall and Sen Slope estimator tests the precipitation trends. Empirical orthogonal function (EOF), pixel-wise correlation, and detrended cross-correlation (DCCA) were employed to investigate the dominant precipitation patterns and their relationships with regional climatic impacts, while the wavelet analysis determines ocean-atmospheric factors in the time-frequency domain. The SAI correlation strongly relates to CRU-CHIRPS for precipitation estimates in North America (NA) R2 = 0.84, Europe R2 = 0.71, and South America (SA), whereas CRU-ERA5 showed better results in the Asian highlands R2 = 0.29, highlighting regional differences in the precipitation dynamics. For precipitation, EOF1 showed a positive variance in most highland regions, but a negative variance prevailed in the Tibetan Plateau (TP), whereas EOF1–2 explained ∼32%, 33%, and 30% variance globally for ERA, CRU, and CHRIPS, respectively. A strong positive correlation is observed between precipitation and mean temperature (TMP) in North America (NA) and the European Alps. However, a significant negative correlation prevailed in the TP and some parts of NA, indicating that these factors can significantly influence the precipitation dynamics in the highlands. Additionally, Detrended Cross-Correlation Analysis (DCCA) has verified that there are positive correlations between precipitation and key climatic factors such as total column water vapor (TCWV), potential evaporation (PEV), and soil moisture (SM). In addition, the influence of ocean-atmospheric (interannual and decadal) coherence patterns originating from the Pacific and Atlantic Oceans indicates a significant impact on precipitation variability, especially in the Asian highlands. This study can contribute to a better understanding of mechanisms and serve as a reference for forecasting precipitation dynamics to develop corresponding strategies in global highlands.

Region, Location, and Age-Specific Comparison of Nutritional Status of In-School Adolescent Girls (10-19 years) in Nigeria

Objective: This study was conducted to assess the nutritional status of adolescent girls using anthropometric indices. Methods: Descriptive cross-sectional study of 2261 in-school adolescent girls aged 10 -19 was conducted. A multistage stratified random sampling procedure was used to select participants from three geopolitical zones in Nigeria. Two states selected from each zone; North Central (Kogi and Niger States), South East (Abia and Imo States) and South West (Osun and Ondo States). Body Mass Index-for-age, Waist-Hip-Ratio (WHR), and Waist-Height-Ratio were calculated by anthropometry of weight, height, hip, waist and Mid-Upper Arm Circumferences. Data were analysed on SPSS Version 24. Frequency, percentages, mean and standard deviations were used for descriptive while logistic regression and chi-square analyses were used for inferential statistics. Significance was taken at p<0.05. Results: Mean age was 14.86 years (± 1.78 years) and actual body weight was 47.81 kg (± 9.02 kg), which is lower than the ideal weight of 54.52 kg (± 9.05 kg). The negative variance of -6.71 kg shows that the girls weighed 6.71 (±9.73) kg less than their ideal weight. Overweight/Obesity/Risk of Abdominal Obesity was highest in South East region (p = .005) while underweight/undernourishment was highest in South West (p = .005). However, no significant difference was recorded between the urban and peri-urban populations (p = .005). Older girls; 14 -16yrs (OR = 2.311, 95%CI = 1.263 – 4.229) and 17 -19yrs (OR = 2.182, 95%CI = 1.253 – 3.799) were twice more likely to be Overweight/Obesity compared to 10 -13yrs. Those who were within the 14 -16yrs age range were thrice more likely to have higher WHR (OR = 3.043 95%CI = 2.334 -3.978) than those younger. Conclusion: There was a significant difference in the nutritional status of adolescent girls across regions and age ranges hence a need for regional nutrition-sensitive intervention programmes among adolescent girls. Keywords: High School Girls; Health Status; Body Stature; Body Measurement; Nigeria Region

Effect of Risk Assessment and Management on Operational Performance of Kenya Revenue Authority

Purpose: Operational performance require effective and efficient internal control mechanisms to check on any leakages, cost of revenue mobilization, negative variance concern on revenue targets among other aspects. The study explained the effect of risk assessment and management on operational performance of KRA Methodology/Approach: Causal design that outline the cause and effect association of risk assessment and management on operational performance. Targeted of finance employees, audit employees and investigation employees adding up to 253 of which 155 were sampled. Findings: Risk assessment and management reported a significant relationship with operational performance of Kenya Revenue Authority. The association was further reported as negative on basic element of risk factor. Implications: KRA management should assess risk and provide mitigation measures that could lead to operational performance. Risk decisions should be well made. That KRA should up audit exercises and conduct interim as well as final audits and make use of audit recommendations given to enable operational performance. Finally, the study recommends that KRA should always make financial reports in accordance to law and hence review them to establish areas to be improved for operation performance.

Effects of distal ulnar morphology on symptomatic extensor carpi ulnaris (ECU) subluxation and the clinical outcomes of anatomic ECU subsheath reconstruction: a retrospective observational study

Purpose: This study aimed to evaluate the association between distal ulnar morphology and symptomatic extensor carpi ulnaris (ECU) subluxation and assess the results of anatomic ECU subsheath reconstruction.Methods: To investigate the effects of distal ulnar morphology on symptomatic ECU subluxation, we compared distal ulnar morphology using magnetic resonance imaging among three groups: group 1 (symptomatic ECU subluxation, 12 cases), group 2 (non-symptomatic ECU subluxation, 24 cases), and group 3 (no ECU subluxation, 24 cases). Distal ulnar morphology was evaluated using ulnar variance, ulnar styloid length, and ECU groove depth. Clinical outcomes were evaluated using the Patient-Related Wrist Evaluation (PRWE) score, the Disabilities of the Arm, Shoulder, Hand (DASH) score, grip strength, and the range of motion of the wrist joint.Results: Ulnar variance showed a statistically significant difference between groups 1 and 2, and ECU groove depth showed statistically significant differences between groups 1 and 2 and between groups 2 and 3. Ulnar styloid length showed no statistically significant between-group differences. In patients with symptomatic ECU subluxation, there was a significant increase in the range of motion in supination and grip strength, and a significant decrease in the DASH score (from 40 to 9) and PRWE score (from 48 to 12). Conclusion: Negative ulnar variance was associated with symptomatic ECU subluxation, and shallow ECU groove depth was correlated to asymptomatic ECU subluxation, but unrelated to symptoms. Anatomic ECU tendon sheath reconstruction was identified as an effective surgical method.

Negative variance components and intercept-slope correlations greater than one in magnitude: How do such "non-regular" random intercept and slope models arise, and what should be done when they do?

Statistical models with random intercepts and slopes (RIAS models) are commonly used to analyze longitudinal data. Fitting such models sometimes results in negative estimates of variance components or estimates on parameter space boundaries. This can be an unlucky chance occurrence, but can also occur because certain marginal distributions are mathematically identical to those from RIAS models with negative intercept and/or slope variance components and/or intercept-slope correlations greater than one in magnitude. We term such parameters "pseudo-variances" and "pseudo-correlations," and the models "non-regular." We use eigenvalue theory to explore how and when such non-regular RIAS models arise, showing: (i) A small number of measurements, short follow-up, and large residual variance increase the parameter space for which data (with a positive semidefinite marginal variance-covariance matrix) are compatible with non-regular RIAS models. (ii) Non-regular RIAS models can arise from model misspecification, when non-linearity in fixed effects is ignored or when random effects are omitted. (iii) A non-regular RIAS model can sometimes be interpreted as a regular linear mixed model with one or more additional random effects, which may not be identifiable from the data. (iv) Particular parameterizations of non-regular RIAS models have no generality for all possible numbers of measurements over time. Because of this lack of generality, we conclude that non-regular RIAS models can only be regarded as plausible data-generating mechanisms in some situations. Nevertheless, fitting a non-regular RIAS model can be acceptable, allowing unbiased inference on fixed effects where commonly recommended alternatives such as dropping the random slope result in bias.

Do Commercial Place Managers Explain Crime Across Places? Yes and NO(PE)

ObjectivesSome criminologists of place have argued that property owners and place managers are the key actors exerting guardianship over crime and driving differences in crime across places, giving rise to the “Neighborhoods Out of Places Explanation” (NOPE) theory of crime. However, research to date has yet to fully evaluate if crime statistically varies across properties, their owners, or surrounding geographies.MethodsData scraped from Yelp.com is used to identify 1070 land parcels that had at least one business receiving reviews from 2014 to 2020. 911 dispatches for disturbances are linked to parcels and measured as the rate of events per Yelp reviewer in the average year. Hierarchical negative binomial modeling-based variance decomposition techniques are used to evaluate how variation in disturbance rates is distributed across parcels, owners, census blocks, and census tracts. Hierarchical negative binomial models are used to assess the correlates of disturbance rates. Sensitivity analyses assess the correlates of disturbance rates using a single-level negative binomial model with bootstrapped standard errors as well as an alternative outcome measure based on count of 911 events.ResultsCommercial disturbance rates vary across parcels, parcel owners, and blocks. At the parcel level, higher Yelp ratings are associated with lower disturbance rates while parcel square footage and land value are associated with increased disturbance rates. Additionally, parcel-level crime disturbance rates are explained by block features such as poverty, violent crime, and the number of Yelp restaurants on the block.ConclusionsParcel, owner, and block features can all help explain why some restaurants have more crime than others. Future research should build on the place management perspective by investigating the wider breadth of potential actors who may exert guardianship over properties while acknowledging that offenders and targets systematically vary across geographies, making effective guardianship more difficult in some locations than others.

Response of Ecosystem Carbon–Water Fluxes to Extreme Drought in West Asia

Global warming has resulted in increases in the intensity, frequency, and duration of drought in most land areas at the regional and global scales. Nevertheless, comprehensive understanding of how water use efficiency (WUE), gross primary production (GPP), and actual evapotranspiration (AET)-induced water losses respond to exceptional drought and whether the responses are influenced by drought severity (DS) is still limited. Herein, we assess the fluctuation in the standardized precipitation evapotranspiration index (SPEI) over the Middle East from 1982 to 2017 to detect the drought events and further examine standardized anomalies of GPP, WUE, and AET responses to multiyear exceptional droughts, which are separated into five groups designed to characterize the severity of extreme drought. The intensification of the five drought events (based on its DS) increased the WUE, decreased the GPP and AET from D5 to D1, where both the positive and negative variance among the DS group was statistically significant. The results showed that the positive values of standardized WUE with the corresponding values of the negative GPP and AET were dominant (44.3% of the study area), where the AET values decreased more than the GPP, and the WUE fluctuation in this region is mostly controlled by physical processes, i.e., evaporation. Drought’s consequences on ecosystem carbon-water interactions ranged significantly among eco-system types due to the unique hydrothermal conditions of each biome. Our study indicates that forthcoming droughts, along with heightened climate variability, pose increased risks to semi-arid and sub-humid ecosystems, potentially leading to biome restructuring, starting with low-productivity, water-sensitive grasslands. Our assessment of WUE enhances understanding of water-carbon cycle linkages and aids in projecting ecosystem responses to climate change.

Analisis Penerapan Akuntansi Berbasis Akrual atas Pendapatan menurut Undang-Undang Perpajakan pada PT. Merapi Utama Pharma Medan

The purpose of writing this thesis is to examine the application of accrual-based accounting to income carried out by PT. Merapi Utama Pharma Medan, in accordance with applicable laws and regulations. This research uses descriptive analysis methodology. The methodology used in this research involves the use of descriptive statistical analysis for data analysis purposes. The second category of data used in this research consists of information originating from official company documents. Data collection methods used in this research include interviews, surveys, and examination of financial records and other related documents. This research tests and evaluates the implementation of income accrual accounting in accordance with Indonesian laws and regulations (Tax Law) at PT. Merapi Utama Pharmacy, Medan. This research is supported by the use of accessible data, allowing the author to obtain important findings. Company PT. Merapi Utama Pharma Medan has not fully implemented payroll accounting practices in accordance with the requirements and deadlines specified in the relevant tax regulations. Reconciliation reports are generated due to differences in the accounting treatment of income and expenses between the two systems. Financial reconciliation can be classified into two categories based on their duration: permanent and temporary. Financial statements are needed to reconcile the difference between positive and negative cash flow variances. Differences in taxable income can be caused by the recognition of certain expenses in the tax records which are not considered as such in the financial records; These expenses have the capacity to reduce an organization's taxable income.

COST AND TIME ANALYSIS USING EARNED VALUE METHOD ON THE CONSTRUCTION OF THE NATIONAL KEDIRI AIRPORT ACCESS ROAD PHASE 1 KEDIRI - NGANJUK

Project completion delays have adverse consequences on a contractor's credibility and result in additional penalty costs, reducing potential profits. To mitigate these issues and optimize project outcomes, refining activity schedules and budgets is crucial. The Earned Value Method proves effective in monitoring and controlling project activities. In the case of the Kediri airport access road construction project, weeks 1 to 6 revealed a negative Cost Variance (CV), indicating higher-than-planned costs, while weeks 7 to 8 showed a positive CV, suggesting costs were lower than anticipated. Schedule Variance (SV) for the 1st week was unfavorable, indicating a delay, and SV>1 from weeks 2 to 8 signaled a project delay. The Estimate to Complete (ETC) is IDR 17,470,510,292.77, and the Estimate at Complete (EAC) is IDR 32,509,153,464.05. The Time Estimate (TE) forecasts project completion in 89 calendar days, five days beyond the contracted 84 days. Employing the Earned Value Method enhances project performance evaluation and decision-making to avoid delays and cost overruns.

The Effect of Radial Inclination on the Stage of Kienbock Disease at the Time of Initial Diagnosis.

Negative ulnar variance is a widely accepted risk factor for the development of Kienbock disease (KD). Variation in radial inclination has been proposed as a risk factor, but evidence thus far has been inconclusive. We aim to clarify the relationship between radial inclination and KD. A retrospective analysis of all KD patients from a single institution from 2007 to 2021 was conducted. Radiographs were reviewed to measure anatomic parameters and stage of disease. An exploratory multinomial regression model was created to examine the association of patient age, radial height, ulnar variance, radial inclination, volar tilt, scapholunate angle, duration of symptoms prior to evaluation, history of wrist trauma, and diagnosis of diabetes with stage of disease. Fifty-seven cases of KD were identified, with a mean duration of disease of 33.3 months. A history of trauma to the wrist was common (53%) and significantly associated with stage of disease at initial presentation. Twenty-seven cases (47%) were stage IIIB or greater. The average initial radial inclination, radial height, and ulnar variance was 21.9°, 10.7 mm, and -1.23 mm, respectively. A multinominal logistic regression model revealed decreased initial radial inclination is associated with Lichtman stage IIIB or greater at the time of initial patient presentation. A correlation exists between decreased radial inclination and more advanced KD at presentation, suggesting this may be a risk factor for disease progression. This correlation is strengthened by our finding of decreased ulnar variance being associated with later stage at presentation, which is one of the most widely accepted proposed risk factors for development and progression of disease. IV.

Comparison of Radiographic Measurement Parameters of the Wrist in Patients with and without Scaphoid Fracture after Fall on an Outstretched Hand.

To investigate the effects of anatomical variations on the mechanism of scaphoid fracture by comparing the radiologic parameters of the wrist of patients with and without scaphoid fracture after a fall on an outstretched hand. Cross-sectional comparative retrospective analysis of radiographs of patients with (Group 1, n=169) and without scaphoid fracture (Group 2, n=188). Morphometric data were measured including radial inclination (RI), radial height (RH), ulnar variance (UV), carpal height (CH) ratio, revised carpal height (RCH) ratio and palmar tilt of the distal radius (PT). Receiver operating characteristics (ROC) curve analysis was used to assess the diagnostic performance for each variable with statistically significant difference. The mean RI and PT degrees and RH length were statistically significantly higher, and the mean UV was lower in Group 1 compared to Group 2. No difference was determined between the groups with respect to the CH ratio and RCH ratio. With ROC curve analysis, the cut-off value with the highest odds ratio was determined as RH (Cut-off value=10.77 mm, OR=21.886). Although higher RI, RH, PT values and more negative ulnar variance were observed in the scaphoid fracture group compared to the non-fracture group, ROC curve analysis showed that only increased RH can be considered as a possible risk factor for scaphoid fractures after fall on an outstretched hand. radiographs, risk factor, scaphoid fracture, wrist morphology.

Impact of Learnability Quotient on Employability of Students: Mediating Role of Spiritual Intelligence

This study investigates the impact of Learnability Quotient (LQ) on Employability, with a particular focus on the mediating role of Spiritual Intelligence (SI). Conducted in southern India with a cross-sectional design, the research utilizes primary data collected from educated adults through surveys. The study aims to elucidate cause-and-effect relationships between LQ and Employability and to test hypotheses regarding these variables. The findings reveal that Learnability Quotient and Employability significantly influence each other, with both being affected by age. Education also plays a crucial role in determining employability, while Spiritual Intelligence and Learnability Quotient are less influenced by educational level. The type of institution does not significantly affect these factors, although the location of the institution does impact Spiritual Intelligence and Employability. Correlation analysis shows that higher Spiritual Intelligence correlates moderately with both Learnability Quotient and Employability, while Learnability Quotient has a strong positive association with Employability. Mediation analysis uncovers a complex dynamic where, despite the positive direct effect of Learnability Quotient on Employability, its impact is diminished when mediated through Spiritual Intelligence, as indicated by a negative Variance Accounted For (VAF). Learnability Quotient is crucial for enhancing employability, while Spiritual Intelligence has a nuanced, potentially counterproductive mediation role. Further research is necessary to refine strategies for improving employability through these variables.

Growth, body composition, and endocrine-metabolic profiles of individuals with Kleefstra syndrome provide directions for clinical management and translational studies.

Mendelian neurodevelopmental disorders caused by variants in genes encoding chromatin modification can be categorized as Mendelian disorders of the epigenetic machinery (MDEMs). These disorders have significant overlap in molecular pathways and phenotypes including intellectual disability, short stature, and obesity. Among the MDEMs is Kleefstra syndrome (KLFS), which is caused by haploinsufficiency of EHMT1. Preclinical studies have identified metabolic dysregulation and obesity in KLFS models, but proper clinical translation lacks. In this study, we aim to delineate growth, body composition, and endocrine-metabolic characteristics in a total of 62 individuals with KLFS. Our results revealed a high prevalence of childhood-onset overweight/obesity (60%; 28/47) with disproportionately high body fat percentage, which aligns perfectly with previous preclinical studies. Short stature was common (33%), likely due to advanced skeletal maturation. Endocrine-metabolic investigations showed thyroid dysregulation (22%; 9/41), elevated triglycerides, and decreased blood ammonia levels. Moreover, hand radiographs identified decreased bone mineralization (57%; 8/14) and negative ulnar variance (71%; 10/14). Our findings indicate a high (cardio)metabolic risk in KLFS. Therefore, we recommend monitoring of weight and endocrine-metabolic profile. Supporting a healthy lifestyle and screening of bone mineralization is advised. Our comprehensive results support translational research and contribute to a better understanding of MDEM-associated phenotypes.

Extensor Carpi Ulnaris “Turn Around” Ligamentoplasty For Distal Radioulnar Joint Instability

Extensor Carpi Ulnaris “Turn Around” Ligamentoplasty For Distal Radioulnar Joint Instability

Association of ulnar variance with three-dimensional carpal alignment and demographics in asymptomatic volunteers.

Several carpal pathologies are considered to be related to ulnar variance. Recently, computer-aided computed tomography (CT) analysis software was introduced to quantify three-dimensional (3D) carpal alignment with high accuracy and reliability. To determine the association of ulnar variance with 3D carpal alignment and demographics. A wrist of 121 asymptomatic volunteers (69 men, 52 women; mean age = 38 ± 10.4 years) was imaged in the neutral wrist position with cone-beam CT. Computer-aided CT analysis software (Bonelogic), based on segmentation and numerical modelling, was used to define ulnar variance and standardized 3D axes for all carpal bones. The association of ulnar variance with 3D carpal alignment, age of the volunteer, and side and dominance of the imaged wrist was assessed. The mean ulnar variance was -1.6 ± 1.5 mm (range = -5.3 to 2.4 mm). The mean ulnar variance was -1.9 mm and -1.1 mm in men and women (P = 0.007), respectively. Of the imaged 121 wrists, 18 (15%) had positive and 103 (85%) negative ulnar variance. There was no association between ulnar variance and any of the radio- or intercarpal angle values in either the sagittal or coronal plane (ρ = -0.16…0.17, r = -0.13….0.12). The ulnar variance showed no association with side (P = 0.51) or dominance (P = 0.27) of the imaged wrist. 3D carpal alignment is not affected by ulnar variance. The association of ulnar variance with sex may in part explain the difference in reported prevalence of some carpal pathologies, such as ulnar impaction syndrome and Kienböck's disease.