Initial clinical experience with durvalumab plus tremelimumab in patients with unresectable hepatocellular carcinoma in real­world practice.

Although durvalumab plus tremelimumab (Dur/Tre) has been approved as first-line therapy for patients with unresectable hepatocellular carcinoma (u-HCC), its outcomes in real-world clinical practice are unclear. The present study aimed to evaluate the efficacy and safety of Dur/Tre treatment. This multicenter study was conducted between March 2023 and January 2024, and included 120 patients with u-HCC treated with Dur/Tre. Among the patients, 44 had no history of systemic treatment. Progression-free survival (PFS), therapeutic response and adverse events (AEs) were assessed. The objective response rate (ORR) and disease control rates (DCR) were 15.8 and 53.3%, respectively. The median PFS was 3.9 months. The incidence rates of AEs of any grade and those grade 3 or higher were 83.3 and 36.7%, respectively. Liver injury was the most frequent AE of any grade and grade 3 or higher. Although there was no significant difference in ORR and PFS between the first and later line groups (ORR 15.8 vs. 15.7%, P=0.986; PFS 4.5 vs. 3.6 months, P=0.213), there was a significant difference in DCR between the two groups (65.8 vs. 45.9%, P=0.034). No significant differences were noted between the first- and later-line treatment groups regarding the incidence rate of AEs. Decision tree analysis revealed that poor liver function and advanced age were significant variables for discontinuation owing to AEs. In conclusion, Dur/Tre as first-line therapy had better disease control responses compared with later-line therapy; however, this regimen should be carefully administered to patients with deteriorating hepatic function or advanced age.

The Agreement between Wearable Sensors and Force Plates for the Analysis of Stride Time Variability.

The variability and regularity of stride time may help identify individuals at a greater risk of injury during military load carriage. Wearable sensors could provide a cost-effective, portable solution for recording these measures, but establishing their validity is necessary. This study aimed to determine the agreement of several measures of stride time variability across five wearable sensors (Opal APDM, Vicon Blue Trident, Axivity, Plantiga, Xsens DOT) and force plates during military load carriage. Nineteen Australian Army trainee soldiers (age: 24.8 ± 5.3 years, height: 1.77 ± 0.09 m, body mass: 79.5 ± 15.2 kg, service: 1.7 ± 1.7 years) completed three 12-min walking trials on an instrumented treadmill at 5.5 km/h, carrying 23 kg of an external load. Simultaneously, 512 stride time intervals were identified from treadmill-embedded force plates and each sensor where linear (standard deviation and coefficient of variation) and non-linear (detrended fluctuation analysis and sample entropy) measures were obtained. Sensor and force plate agreement was evaluated using Pearson's r and intraclass correlation coefficients. All sensors had at least moderate agreement (ICC > 0.5) and a strong positive correlation (r > 0.5). These results suggest wearable devices could be employed to quantify linear and non-linear measures of stride time variability during military load carriage.

The Effect of a Cognitive Dual Task on Gait Parameters among Healthy Young Adults with Good and Poor Sleep Quality: A Cross-Sectional Analysis.

Background: Sleep quality is known to affect automatic and executive brain functions such as gait control and cognitive processing. This study aimed to investigate the effect of dual tasks on gait spatiotemporal parameters among young adults with good and poor sleep quality. Methods: In total, 65 young adults with a mean age of 21.1 ± 2.5 were assessed for gait analysis during single-task and dual-task conditions. The participants' sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI) and gait was assessed using the BTS Gaitlab System. The participants were asked to walk at natural speed as a single-task condition, followed by walking while performing a cognitive task as a dual-task condition. The parameters assessed included the gait velocity (m/s), cadence (steps/min), step width (m), and stride length (m). The dual-task cost (DTC) on each gait parameter was calculated. The Mann-Whitney U test was used to compare the differences in the DTC on gait variables between the good and poor sleep quality groups and the Spearman correlation test was used to assess the correlation between total PSQI scores and the DTC. Results: At a significance level of p < 0.05, a significant difference in cadence between the two sleep quality groups was observed, in addition to a positive correlation between sleep quality and the DTC effect on gait mean velocity, cadence, and stride length. Our findings also revealed a greater DTC in participants with poorer sleep quality. Conclusions: These findings contribute to our perception of the significance of sleep quality in gait performance while multitasking in younger populations.

Proportion of inflammatory bowel diseases patients with suboptimal disease control in daily clinical practice-Real-world evidence from the inflammatory bowel diseases-podcast study.

BACKGROUND: Crohn's disease and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) characterized by a progressive nature of the disease resulting in subsequent intestinal damage, limited efficacy of current treatments and suboptimal disease management and a significant burden for patients. OBJECTIVES: The IBD-PODCAST study aims to estimate the proportion of Crohn's disease and UC patients with suboptimal disease control (SDC) in a real-world setting. METHODS: A non-interventional and cross-sectional study was conducted across 103 sites in 10 countries (Austria, Belgium, Canada, Germany, Greece, Italy, Portugal, Spain, Turkey, and UK). Criteria for SDC were based on STRIDE-II criteria and adapted by an expert panel. RESULTS: 2185 patients (Crohn's disease: n = 1,108, UC: n = 1077) with a mean (SD) age of 44.0 (14.8) years and mean (SD) disease duration of 12.4 (9.2) years were included (52.2% male). Ileal involvement was present in 39.1% of Crohn's disease patients, 35.3% of UC patients had extensive colitis. 77.3% of Crohn's disease and 65.3% of UC patients were on targeted immunomodulators and, according to STRIDE-II-based treatment phases, 85.6% of Crohn's disease and 85.4% of UC patients were assigned to the long-term treatment phase. SDC was detected in 52.2% of Crohn's disease and 44.3% of UC patients predominantly due to impaired quality of life (QoL), clinically significant extraintestinal manifestations, steroid overuse, signs of active inflammation in UC and Crohn's disease, and active fistulas in Crohn's disease. More than one criterion was seen in 37% of patients with SDC. Opportunities for on-label treatment optimization were observed in 49% of Crohn's disease and 61% of UC patients on advanced therapy. CONCLUSION: The high percentage of SDC in this global, real-world cohort suggests a large disease burden and high unmet medical need in IBD patients. Future analysis should focus on monitoring and responding to SDC in this cohort and on patients' QoL.

Assessing readiness to use electronic health record data for outcome ascertainment in clinical trials - A case study.

BACKGROUND: Variable data quality poses a challenge to using electronic health record (EHR) data to ascertain acute clinical outcomes in multi-site clinical trials. Differing EHR platforms and data comprehensiveness across clinical trial sites, especially if patients received care outside of the clinical site's network, can also affect validity of results. Overcoming these challenges requires a structured approach. METHODS: We propose a framework and create a checklist to assess the readiness of clinical sites to contribute EHR data to a clinical trial for the purpose of outcome ascertainment, based on our experience with the Strategies to Reduce Injuries and Develop Confidence in Elders (STRIDE) study, which enrolled 5451 participants in 86 primary care practices across 10 healthcare systems (sites). RESULTS: The site readiness checklist includes assessment of the infrastructure (i.e., size and structure of the site's healthcare system or clinical network), data procurement (i.e., quality of the data), and cost of obtaining study data. The checklist emphasizes the importance of understanding how data are captured and integrated across a site's catchment area and having a protocol in place for data procurement to ensure consistent and uniform extraction across each site. CONCLUSIONS: We suggest rigorous, prospective vetting of the data quality and infrastructure of each clinical site before launching a multi-site trial dependent on EHR data. The proposed checklist serves as a guiding tool to help investigators ensure robust and unbiased data capture for their clinical trials. ORIGINAL TRIAL REGISTRATION NUMBER: NCT02475850.

Associations between Racing Thoroughbred Movement Asymmetries and Racing and Training Direction.

BACKGROUND: Racehorses commonly train and race in one direction, which may result in gait asymmetries. This study quantified gait symmetry in two cohorts of Thoroughbreds differing in their predominant exercising direction; we hypothesized that there would be significant differences in the direction of asymmetry between cohorts. METHODS: 307 Thoroughbreds (156 from Singapore Turf Club (STC)-anticlockwise; 151 from Hong Kong Jockey Club (HKJC)-clockwise) were assessed during a straight-line, in-hand trot on firm ground with inertial sensors on their head and pelvis quantifying differences between the minima, maxima, upward movement amplitudes (MinDiff, MaxDiff, UpDiff), and hip hike (HHD). The presence of asymmetry (≥5 mm) was assessed for each variable. Chi-Squared tests identified differences in the number of horses with left/right-sided movement asymmetry between cohorts and mixed model analyses evaluated differences in the movement symmetry values. RESULTS: HKJC had significantly more left forelimb asymmetrical horses (Head: MinDiff p < 0.0001, MaxDiff p < 0.03, UpDiff p < 0.01) than STC. Pelvis MinDiff (p = 0.010) and UpDiff (p = 0.021), and head MinDiff (p = 0.006) and UpDiff (p = 0.017) values were significantly different between cohorts; HKJC mean values indicated left fore- and hindlimb asymmetry, and STC mean values indicated right fore- and hindlimb asymmetry. CONCLUSION: the asymmetry differences between cohorts suggest that horses may adapt their gait to their racing direction, with kinematics reflecting reduced 'outside' fore- and hindlimb loading.

MRUNet-3D: A multi-stride residual 3D UNet for lung nodule segmentation.

Obtaining an accurate segmentation of the pulmonary nodules in computed tomography (CT) images is challenging. This is due to: (1) the heterogeneous nature of the lung nodules; (2) comparable visual characteristics between the nodules and their surroundings. A robust multi-scale feature extraction mechanism that can effectively obtain multi-scale representations at a granular level can improve segmentation accuracy. As the most commonly used network in lung nodule segmentation, UNet, its variants, and other image segmentation methods lack this robust feature extraction mechanism. In this study, we propose a multi-stride residual 3D UNet (MRUNet-3D) to improve the segmentation accuracy of lung nodules in CT images. It incorporates a multi-slide Res2Net block (MSR), which replaces the simple sequence of convolution layers in each encoder stage to effectively extract multi-scale features at a granular level from different receptive fields and resolutions while conserving the strengths of 3D UNet. The proposed method has been extensively evaluated on the publicly available LUNA16 dataset. Experimental results show that it achieves competitive segmentation performance with an average dice similarity coefficient of 83.47 % and an average surface distance of 0.35 mm on the dataset. More notably, our method has proven to be robust to the heterogeneity of lung nodules. It has also proven to perform better at segmenting small lung nodules. Ablation studies have shown that the proposed MSR and RFIA modules are fundamental to improving the performance of the proposed model.

Dirt Track Surface Preparation and Associated Differences in Speed, Stride Length, and Stride Frequency in Galloping Horses.

In racehorses, the risk of musculoskeletal injury is linked to a decrease in speed and stride length (SL) over consecutive races prior to injury. Surface characteristics influence stride parameters. We hypothesized that large changes in stride parameters are found during galloping in response to dirt racetrack preparation. Harrowing of the back stretch of a half-mile dirt racetrack was altered in three individual lanes with decreasing depth from the inside to the outside. Track underlay compaction and water content were changed between days. Twelve horses (six on day 2) were sequentially galloped at a target speed of 16 ms-1 across the three lanes. Speed, stride frequency (SF), and SL were quantified with a GPS/GNSS logger. Mixed linear models with speed as covariate analyzed SF and SL, with track hardness and moisture content as fixed factors (p < 0.05). At the average speed of 16.48 ms-1, hardness (both p < 0.001) and moisture content (both p < 0.001) had significant effects on SF and SL. The largest difference in SL of 0.186 m between hardness and moisture conditions exceeded the 0.10 m longitudinal decrease over consecutive race starts previously identified as injury predictor. This suggests that detailed measurements of track conditions might be useful for refining injury prediction models.

Stride Velocity 95th Centile Detects Decline in Ambulatory Function Over Shorter Intervals than the 6-Minute Walk Test or North Star Ambulatory Assessment in Duchenne Muscular Dystrophy.

Background: Stride Velocity 95th Centile (SV95C) is the first wearable device-derived clinical outcome assessment (COA) to receive European Medicines Agency (EMA) qualification as a primary endpoint in ambulant patients with Duchenne muscular dystrophy (DMD) aged ≥4 years. Objective: To compare SV95C-in its first-ever clinical trial application as a secondary endpoint-with established motor function COAs used in the trial (Four-Stair Climb [4SC] velocity, North Star Ambulatory Assessment [NSAA], and Six-Minute Walk Distance [6MWD]). Methods: SV95C was a secondary endpoint in a subset (n = 47) of participants in the SPITFIRE/WN40227 trial of taldefgrobep alfa, which was discontinued due to lack of clinical benefit. Participants in the ≤48-week SV95C sub-study were 6-11 years old and received corticosteroids for ≥6 months pre-treatment. Pearson correlations were used to compare SV95C with the other COAs. Responsiveness and changes over time were respectively assessed via standardized response means (SRMs) based on absolute changes and mixed models for repeated measures. Results: SV95C change at Week 24 was -0.07 m/s, with limited variability (standard deviation: 0.16, n = 27). The SRM for SV95C indicated moderate responsiveness to clinical change at the earliest timepoint (Week 12, n = 46), while those of the other COAs did not indicate moderate responsiveness until Week 36 (6MWD, n = 33) or Week 48 (4SC velocity, n = 20; NSAA total score, n = 20). Baseline correlations between SV95C and other COAs were strong (r = 0.611-0.695). Correlations between SV95C change from baseline to Week 48 and changes in other COAs were moderate to strong (r = 0.443-0.678).∥. Conclusions: Overall, SV95C demonstrated sensitivity to ambulatory decline over short intervals, low variability, and correlation with established COAs. Although the negative trial precluded demonstration of SV95C's sensitivity to drug effect, these findings support the continued use of SV95C in DMD clinical trials.

Walking around the preferred speed: examination of metabolic, perceptual, spatiotemporal and stability parameters.

Walking is the most accessible and common type of physical activity. Exercising at one's self-selected intensity could provide long-term benefits as compared to following prescribed intensities. The aim of this study was to simultaneously examine metabolic, perceptual, spatiotemporal and stability parameters at an absolute 3 km·h-1 speed range around the individual preferred walking speed (PWS). Thirty-four young sedentary adults (18 women) volunteered to walk at seven speeds relative to their PWS in 3-min trials interspaced with 3-min rest intervals. Results indicated a significant main effect of speed on all studied variables. While metabolic, perceptual and spatiotemporal values were sensitive to the smallest change in speed (i.e., 0.5 km·h-1), a significant increase in the rate of carbohydrate oxidation and decrease in %fat oxidation were only observed at speeds above PWS. Results also revealed significantly higher coefficients of variation for stride characteristics at speeds below PWS only. Moreover, analyses of best fit models showed a quadratic relationship between most variables and speed, with the exceptions of metabolic cost of transport, rating of perceived exertion and stride duration that changed exponentially with speed. PWS coincided with optimized mechanical efficiency, fuel oxidation and gait stability. This indicated that walking below PWS decreased both mechanical efficiency and stability of gait, while walking above PWS increased carbohydrate oxidation. Those factors seem to play an important role as determinants of PWS. We suggest that walking at PWS may provide benefits in terms of fat oxidation while optimizing gait stability.

Impaired dual-task gait in Parkinson's disease is associated with brain morphology changes.

In Parkinson's disease (PD), impaired gait and cognition affect daily activities, particularly in the more advanced stages of the disease. This study investigated the relationship between gait parameters, cognitive performance, and brain morphology in patients with early untreated PD. 64 drug-naive PD patients and 47 healthy controls (HC) participated in the study. Single- and dual-task gait (counting task) were examined using an expanded Timed Up & Go Test measured on a GaitRite walkway. Measurements included gait speed, stride length, and cadence. A brain morphometry analysis was performed on T1-weighted magnetic resonance (MR) images. In PD patients compared to HC, gait analysis revealed reduced speed (p < 0.001) and stride length (p < 0.001) in single-task gait, as well as greater dual-task cost (DTC) for speed (p = 0.007), stride length (p = 0.014) and cadence (p = 0.029). Based on the DTC measures in HC, PD patients were further divided into two subgroups with normal DTC (PD-nDTC) and abnormally increased DTC (PD-iDTC). For PD-nDTC, voxel-based morphometric correlation analysis revealed a positive correlation between a cluster in the left primary motor cortex and stride-length DTC (r = 0.57, p = 0.027). For PD-iDTC, a negative correlation was found between a cluster in the right lingual gyrus and the DTC for gait cadence (r=-0.35, pFWE = 0.018). No significant correlations were found in HC. The associations found between brain morphometry and gait performance with a concurrent cognitive task may represent the substrate for gait and cognitive impairment occurring since the early stages of PD.

Gait Characteristics during Dual-Task Walking in Elderly Subjects of Different Ages.

BACKGROUND: In older age, walking ability gradually decreases due to factors including impaired balance, reduced muscle strength, and impaired vision and proprioception. Further, cognitive functions play a key role during walking and gradually decline with age. There is greater variability in gait parameters when the demands during walking increase, in dual- and multiple-task situations. The aim of this study was to analyze gait parameters while performing a demanding cognitive and motor dual task in three different age-related healthy elderly subject groups. METHOD: A total of 132 healthy individuals (54 males, 78 females) were divided into three groups-55 to 65, 66 to 75, and 76 to 85 years. The subjects performed a basic walking task, dual motor task, dual mental task, and combined motor and mental task while walking. The gait parameters cycle time, stride length, swing time, and double support time were noted, as well as the variability of those parameters. RESULTS: Cycle time was longer and stride length was shorter in the >76-year-old group than in the 51-65-year-old group in all test conditions. A comparison of all three groups did not show a significant difference in swing time, while double support time was increased in the same group. CONCLUSIONS: Changes are observed when gait is performed simultaneously with an additional motor or cognitive task. Early detection of gait disorders can help identify elderly people at increased risk of falls. Employing a dual-task paradigm during gait assessment in healthy elderly subjects may help identify cognitive impairment early in the course of the disturbance.

Comparison of speed-dependent time, force and spatial parameters between Franches-Montagnes and European Warmblood horses walking and trotting on a treadmill.

Speed alterations affect many gait analysis parameters. How horses adapt to speed is relevant in many equestrian disciplines and may differ between breeds. This study described changes in gait parameters in 38 Warmblood (WB) and 24 Franches-Montagnes (FM) horses subjected to an incremental speed test at walk (1.35-2.05 m/s) and trot (3.25-5.5 m/s). Time, force and spatial parameters of each limb were measured with an instrumented treadmill and analysed with regression analysis using speed as the independent variable. With higher speeds, stride rate, length, over-tracking distance and vertical ground reaction forces increased while the impulses decreased. The parameters followed the same linear or polynomial regression curves independent of breed, while the slope (linear) or incurvation (polynomial) often differed significantly between breeds. Some differences between the breeds were associated with height and speed (e.g. stride length at walk), and would disappear when scaling the data. The main differences between the breeds seem to stem from the movement of the hind limbs, with the FM obtaining long over-tracking distances despite the shorter height at withers. Some parameters relevant to gait quality could be improved in the FM to resemble WB movement by strict selection using objective measurements systems.

IBD-PODCAST Spain: A Close Look at Current Daily Clinical Practice in IBD Management.

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) that contributes in part to irreversible bowel damage and long-term complications, reduced quality of life, invalidity, and economic burden. Suboptimal control of IBD is associated with higher healthcare resource utilization (HCRU), impaired quality of life (QoL), and reduced work productivity. AIMS: The IBD-PODCAST study aimed to assess the proportion of IBD patients with suboptimal control and its associated impact. METHODS: IBD-PODCAST is a cross-sectional, multicenter study that aimed to characterize the CD and UC population with optimal or suboptimal control according to the STRIDE-II criteria and patient- and physician-reported measures. Here we present the results of the Spanish cohort (n = 396). RESULTS: A total of 104/196 (53.1%) CD and 83/200 (41.5%) UC patients were found to have suboptimal disease control. Long-term treatment targets according to STRIDE-II were applied in 172 (87.8%) CD and 181 (90.5%) UC patients. 125 of 172 (72.7%) CD and 74 of 181 (40.9%) UC patients were currently treated with targeted immunomodulators. Patients with CD and UC and suboptimal disease control showed impaired QoL, higher HCRU and direct costs, and also loss of work productivity compared to those with optimal control. CONCLUSION: Despite a high rate of targeted immunomodulator therapy, a substantial proportion of IBD patients show suboptimal disease control according to the STRIDE II criteria. Those patients with suboptimal disease control exhibit impaired QoL, less work productivity, and higher HCRU, suggesting that there is considerable need for better treatment approaches in IBD.

Reduced center of mass acceleration during regular walking with electromyography biofeedback.

BACKGROUND: Regular walking in healthy adults is known to be kinematically stable, but it is unclear how to further kinematically stabilize regular walking. Electromyography biofeedback (EMG-BF) during walking improves walking ability in patients. However, the effect of EMG-BF on walking stability in healthy adults is unknown. Therefore, this study aimed to investigate whether EMG-BF enhances the stability of regular walking in healthy adults. RESEARCH QUESTION: Does the EMG-BF enhance the stability of regular walking in healthy adults? METHODS: Auditory biofeedback of single muscle activity was given to twelve participants during regular walking. The target muscles were the ankle plantar flexor, ankle dorsiflexor, and knee flexor. We compared the root mean square of the center of mass acceleration (RMS-CoMacc), which represents walking smoothness, between biofeedback conditions. RESULTS: We found that EMG-BF during regular walking partially reduced the RMS-CoMacc (p = 0.01). In particular, biofeedback of the ankle plantar flexor muscle reduced the RMS-CoMacc in both the anteroposterior and vertical directions. In the mediolateral RMS-CoMacc, no significant difference was found (p = 0.24). SIGNIFICANCE: Our study is novel because it is the first study to reveal the impact of EMG-BF on the stability of walking among healthy adults. It identifies the key muscles for EMG-BF, potentially leading to the development of a more effective EMG-BF system in the rehabilitation. Especially, biofeedback of the ankle plantar flexor muscle could improve walking stability in both the anteroposterior and vertical directions. The effect of EMG-BF for reducing the RMS-CoMacc during regular walking might depend on the target muscles of biofeedback.

Longitudinal changes in trunk acceleration and their relationship with gait parameters in post-stroke hemiplegic patients.

OBJECTIVE: The purpose of this study was to examine the longitudinal changes in trunk acceleration, gait speed, and paretic leg motion in patients with post-stroke hemiparesis, the relationships between variables at each time point, and whether initial trunk acceleration and gait parameters were related to gait speed 2 months later. METHODS: Gait was assessed monthly in patients who could walk under supervision after stroke onset. Gait parameters, including gait speed and trailing limb angle (TLA), were measured. Trunk acceleration was quantified using acceleration root mean square (RMS) and stride regularity (SR) indices. RESULTS: This study found statistically significant longitudinal changes in gait speed (p < .001), acceleration RMS of the total axes (p < .001), and SR of the vertical axes (p < .001). Gait speed correlated significantly with the acceleration RMS of the mediolateral (r = -0.815 to -0.901), vertical (r = -0.541 to -0.747), and anteroposterior (r = -0.718 to -0.829) axes, as well as the SR of the vertical axes (r = 0.558 to 0.724) at all time points from T0 to T2. For the TLA, only the acceleration RMS of the mediolateral axis correlated significantly over the entire study period (r = -0.530 to -0.724). In addition, initial TLA correlated significantly with gait speed after 2 months (r = -0.572). CONCLUSION: This study showed that assessing trunk acceleration helps estimate the improvement in gait status in patients with post-stroke hemiparesis. The magnitude and regularity of trunk acceleration varied longitudinally and were related to gait speed and paretic leg motion at each time point; however, they could not predict future changes in gait speed.

Effects of upper arch expansion using clear aligners on different stride and torque: a three-dimensional finite element analysis.

BACKGROUND: During maxillary arch expansion with a clear aligner (CA), buccal tipping of the posterior teeth often occurs, resulting in an unsatisfactory arch expansion effect. The aim of this study was to analyze the appropriate maxillary arch expansion stride length and torque compensation angle for maxillary dentition to achieve an ideal moving state when a CA was used for upper arch expansion. METHODS: This study established a three-dimensional (3D) finite element model including a CA, maxilla, periodontal ligament (PDL), and maxillary dentition. The stress distribution, stress situation, expansion efficiency, and movement trends of the maxillary dentition during upper arch expansion of different stride (0.1 mm, 0.2 mm, and 0.3 mm) and torque compensation (0°, 0.5°, 1°, and 1.5°) were measured. RESULTS: Maxillary arch expansion lead to buccal tilt of the posterior teeth, lingual tilt of the anterior teeth, and extrusion of the incisors. As the angle of compensation increased, the degree of buccal tilt on the posterior teeth decreased, with this reducing the efficiency of upper arch expansion. When the stride length was 0.1 mm, the torque compensation was 1.2°, and when stride length was 0.2 mm and the torque compensation was approximately 2°, there was a tendency for the posterior teeth to move bodily. However, when the stride length was 0.3 mm, the increase in torque compensation could not significantly improve the buccal tilt phenomenon. In addition, the equivalent von-Mises stress values of the maxillary root, PDL, and alveolar bone were in the same order of magnitude. CONCLUSIONS: This study indicated that the posterior teeth cause a degree of buccal tilt when maxillary arch expansion is ensured. The specific torque compensation angle should be determined based on the patient's situation and the desired effect.

Application of vibration to the soles increases long-range correlations in the stride parameters during walking.

Temporal fluctuations in the stride parameters during human walking exhibit long-range correlations, but these long-range correlations in the stride parameters decrease due to aging or neuromuscular diseases. These observations suggest that any quantified index of the long-range correlation can be regarded as an indicator of gait functionality. Considering the effect of task-relevant sensory feedback on augmenting human motor performance, we devised shoes with active insoles that could deliver noisy vibration to the soles of feet and assessed their efficacy in enhancing the long-range correlations in the stride parameters for healthy young adults. The vibration could be wirelessly controlled using a smartphone. The actuators, control unit, and battery in the devised shoes were light and embedded in the shoes. By virtue of this compactness, the shoes could be easily used for daily walking outside a laboratory. We performed walking experiments with 20 healthy adults and evaluated the effects of sub- and supra-threshold vibration on long-range correlations in stride interval and length. We performed detrended fluctuation analysis to quantify the long-range correlation of temporal changes in stride interval and length. We found that supra-threshold vibration, applied to the soles with the amplitude of 130 % of the sensory threshold, significantly increased the long-range correlations in stride interval and length by 10.3 % (p = 0.009) and 10.1 % (p = 0.021), respectively. On the other hand, sub-threshold vibration with the amplitude of 90 % of the sensory threshold had no significant effect. These results demonstrate that additional somatosensory feedback through barely detectable vibrations, which are supplied by compact shoes with active insoles, can enhance the indices of "healthy" complexity of locomotor function.

On the variability and dependence of human leg stiffness across strides during running and some consequences for the analysis of locomotion data.

Typically, animal locomotion studies involve consecutive strides, which are frequently assumed to be independent with parameters that do not vary across strides. This assumption is often not tested. However, failing in particular to account for dependence across strides may cause an incorrect estimate of the uncertainty of the measurements and thereby lead to either missing (overestimating variance) or over-evaluating (underestimating variance) biological signals. In turn, this impacts replicability of the results because variability is accounted for differently across experiments. In this paper, we analyse the changes of a couple of measures of human leg stiffness across strides during running experiments, using a publicly available dataset. A major finding of this analysis is that the time series of these measurements of stiffness show autocorrelation even at large lags and so there is dependence between individual strides, even when separated by many intervening strides. Our results question the practice in biomechanics research of using each stride as an independent observation or of sub-selecting strides at small lags. Following the outcome of our analysis, we strongly recommend caution in doing so without first confirming the independence of the measurements across strides and without confirming that sub-selection does not produce spurious results.

Gait Stride Length Estimation Using Embedded Machine Learning.

INTRODUCTION: Spatiotemporal gait parameters, e.g., gait stride length, are measurements that are classically derived from instrumented gait analysis. Today, different solutions are available for gait assessment outside the laboratory, specifically for spatiotemporal gait parameters. Such solutions are wearable devices that comprise an inertial measurement unit (IMU) sensor and a microcontroller (MCU). However, these existing wearable devices are resource-constrained. They contain a processing unit with limited processing and memory capabilities which limit the use of machine learning to estimate spatiotemporal gait parameters directly on the device. The solution for this limitation is embedded machine learning or tiny machine learning (tinyML). This study aims to create a machine-learning model for gait stride length estimation deployable on a microcontroller. MATERIALS AND METHOD: Starting from a dataset consisting of 4467 gait strides from 15 healthy people, measured by IMU sensor, and using state-of-the-art machine learning frameworks and machine learning operations (MLOps) tools, a multilayer 1D convolutional float32 and int8 model for gait stride length estimation was developed. RESULTS: The developed float32 model demonstrated a mean accuracy and precision of 0.23 ± 4.3 cm, and the int8 model demonstrated a mean accuracy and precision of 0.07 ± 4.3 cm. The memory usage for the float32 model was 284.5 kB flash and 31.9 kB RAM. The int8 model memory usage was 91.6 kB flash and 13.6 kB RAM. Both models were able to be deployed on a Cortex-M4F 64 MHz microcontroller with 1 MB flash memory and 256 kB RAM. CONCLUSIONS: This study shows that estimating gait stride length directly on a microcontroller is feasible and demonstrates the potential of embedded machine learning, or tinyML, in designing wearable sensor devices for gait analysis.