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Journal of Motor Behavior 2024We tested twenty-one 6- to 10-month-old infants with a wide range of sitting experience in forward and rightward reaching during unsupported sitting on the floor....
We tested twenty-one 6- to 10-month-old infants with a wide range of sitting experience in forward and rightward reaching during unsupported sitting on the floor. Sessions were video-recorded for further behavioral and machine learning-based kinematic analyses. All infants, including novice sitters, successfully touched and grasped toys in both directions. Infant falls, hand support, and base of support changes were rare. Infants with more sitting experience showed better upright posture than novice sitters. However, we found no differences in trunk displacement or reaching kinematics between directions or across sitting experience. Thus, multi-directional reaching is functional in both novice and experienced infant sitters. We suggest that trunk and arm stability in sagittal and frontal planes is integral to learning to sit.
Topics: Infant; Humans; Posture; Hand; Standing Position; Biomechanical Phenomena; Postural Balance
PubMed: 37751896
DOI: 10.1080/00222895.2023.2262428 -
Perceptual and Motor Skills Dec 2023Mechanical vibration of the Achilles tendon is widely used to analyze the role of proprioception in postural control. The response to this tendon vibration (TV) has been...
Mechanical vibration of the Achilles tendon is widely used to analyze the role of proprioception in postural control. The response to this tendon vibration (TV) has been analyzed in the upright posture, but the feet positions have varied in past research. Moreover, investigators have addressed only temporal parameters of the center of pressure (CoP). We investigated the effect of TV on both temporal and spectral characteristics of the CoP motion. Eighteen healthy young adults, stood barefoot, with one foot on each side of a dual platform, wearing glasses with opaque lenses. We applied 20 seconds of Achilles TV (bilaterally with inertial vibrators at a frequency of 80 Hz and an amplitude of .2-.5 mm). We analyzed CoP signals pre-vibration (PRE,4-seconds), during vibration (VIB,20 seconds), and after vibration cessation (REC,20 seconds). We repeated this protocol in natural and standardized positions (15° feet angular opening). For determining CoP amplitude and velocity, we divided the 20 seconds into five phases of four seconds each and calculated spectral parameters for the whole 20-second signals. There was an adaptation process in the speed of the CoP mediolateral ( < .01) and anteroposterior ( < .01) and in the displacement of the CoP anteroposterior ( < .01), with higher values in the VIB condition. Velocity and displacement decreased progressively in the REC condition. Median and peak frequencies were higher in the VIB condition when compared to the REC condition, but only in the mediolateral direction ( = .01). The standardized foot position led to increased speed in CoP mediolateral, anteroposterior, and mediolateral displacement ( < .01). CoP spectral characteristics were not affected by foot positioning. We concluded that adaptation of CoP motion in the presence of TV and after its cessation are observable both in time and frequency domains. Feet positioning influenced CoP motion in the presence of TV and after its cessation but it did not affect its spectral characteristics.
Topics: Young Adult; Humans; Achilles Tendon; Vibration; Proprioception; Postural Balance; Standing Position
PubMed: 37654231
DOI: 10.1177/00315125231198161 -
Cureus Sep 2023Introduction Epipharyngeal Abrasive Therapy (EAT) has been used as a treatment for chronic epipharyngitis, and although autonomic nerve stimulation has been pointed out...
Introduction Epipharyngeal Abrasive Therapy (EAT) has been used as a treatment for chronic epipharyngitis, and although autonomic nerve stimulation has been pointed out as one of the mechanisms by which EAT produces therapeutic effects, there have been few reports examining this mechanism of action. This study investigated the effects of repeated EAT on autonomic nervous system activity in chronic epipharyngitis patients over time, using heart rate variability analysis. In addition, we conducted a loading test using the active standing test (AS test) to examine the effects of EAT on the baroreceptor reflex (BR). Subjects and methods A retrospective study was conducted on 39 patients who visited our clinic between July 2017 and November 2019 and underwent autonomic function tests with a diagnosis of chronic nasopharyngeal inflammation. The subjects were divided into two groups: the improvement group and the invariant group for comparison. Electrocardiographic recordings and blood pressure measurements were made under the stress of the AS test. Heart rate, high-frequency (HF) component, low-frequency (LF) component, and Coefficient of Variation on R-R interval were evaluated as indices of autonomic function. Component coefficient of variance high frequency was used as an index of parasympathetic function. ccvLF/ccvHF ratio was calculated by dividing the component coefficient of variance low frequency by ccvHF. The AS test was conducted in phase 1 in the initial resting sitting position, in phase 2 in the standing position, in phase 3 in the standing and holding the standing position, and in phase 4 in the seated and holding the sitting position. Systolic blood pressure, mean arterial pressure, and diastolic blood pressure were obtained in each phase. A paired t-test was used to compare the improved and invariant groups before and after treatment. The post-treatment comparison between the improved group and the invariant group was performed by unpaired t-test. Variation of the evaluation index over time was evaluated by repeated measures ANOVA. Multiple comparisons were corrected by the Bonferroni method. Results The EAT showed that parasympathetic activity was significantly suppressed in the improvement group, while the AS test showed significant fluctuations over time for the improvement and invariant groups. The interaction between the time course and the two factors in the improvement and invariant groups was not statistically evident. Although no significant difference was found, the improvement group showed a tendency to suppress parasympathetic activity and a tendency to stimulate sympathetic activity compared to the invariant group. Blood pressure in the improvement group showed a tendency to decrease. Conclusions EAT was found to suppress parasympathetic activity over time, and the AS test did not reveal an interaction effect of EAT on BR. However, there was a trend toward suppression of parasympathetic activity and stimulation of sympathetic activity in the improved group compared to the invariant group. Blood pressure in the improved group tended to decrease. It is possible that EAT may have a positive effect on autonomic neuropathy symptoms such as orthostatic dysregulation (OD), postural orthostatic tachycardia syndrome (POTS), etc. by stimulating the BRs. It is thought that the autonomic nervous system stimulating action and the immune system stimulating action act synergistically to express the therapeutic effect of EAT.
PubMed: 37705568
DOI: 10.7759/cureus.45080 -
Frontiers in Neuroscience 2023Assessment of human gait posture can be clinically effective in diagnosing human gait deformities early in life. Currently, two methods-static and dynamic-are used to...
INTRODUCTION
Assessment of human gait posture can be clinically effective in diagnosing human gait deformities early in life. Currently, two methods-static and dynamic-are used to diagnose adult spinal deformity (ASD) and other spinal disorders. Full-spine lateral standing radiographs are used in the standard static method. However, this is a static assessment of joints in the standing position and does not include information on joint changes when the patient walks. Careful observation of long-distance walking can provide a dynamic assessment that reveals an uncompensated posture; however, this increases the workload of medical practitioners. A three-dimensional (3D) motion system is proposed for the dynamic method. Although the motion system successfully detected dynamic posture changes, access to the facilities was limited. Therefore, a diagnostic approach that is facility-independent, has low practice flow, and does not involve patient contact is required.
METHODS
We focused on a video-based method to classify patients with spinal disorders either as ASD, or other forms of ASD. To achieve this goal, we present a video-based two-stage machine-learning method. In the first stage, deep learning methods are used to locate the patient and extract the area where the patient is located. In the second stage, a 3D CNN (convolutional neural network) device is used to capture spatial and temporal information (dynamic motion) from the extracted frames. Disease classification is performed by discerning posture and gait from the extracted frames. Model performance was assessed using the mean accuracy, F1 score, and area under the receiver operating characteristic curve (AUROC), with five-fold cross-validation. We also compared the final results with professional observations.
RESULTS
Our experiments were conducted using a gait video dataset comprising 81 patients. The experimental results indicated that our method is effective for classifying ASD and other spinal disorders. The proposed method achieved a mean accuracy of 0.7553, an F1 score of 0.7063, and an AUROC score of 0.7864. Additionally, ablation experiments indicated the importance of the first stage (detection stage) and transfer learning of our proposed method.
DISCUSSION
The observations from the two doctors were compared using the proposed method. The mean accuracies observed by the two doctors were 0.4815 and 0.5247, with AUROC scores of 0.5185 and 0.5463, respectively. We proved that the proposed method can achieve accurate and reliable medical testing results compared with doctors' observations using videos of 1 s duration. All our code, models, and results are available at https://github.com/ChenKaiXuSan/Walk_Video_PyTorch. The proposed framework provides a potential video-based method for improving the clinical diagnosis for ASD and non-ASD. This framework might, in turn, benefit both patients and clinicians to treat the disease quickly and directly and further reduce facility dependency and data-driven systems.
PubMed: 38148942
DOI: 10.3389/fnins.2023.1278584 -
Cavovarus Deformity: Why Weight-Bearing Computed Tomography Should Be a First-Line Imaging Modality.Foot and Ankle Clinics Dec 2023Cavovarus foot is a complex three-dimensional deformity, which includes a wide range of clinical conditions from subtle deformities to disabling feet. In this article,... (Review)
Review
Cavovarus foot is a complex three-dimensional deformity, which includes a wide range of clinical conditions from subtle deformities to disabling feet. In this article, the authors discuss the role of weight-bearing computed tomography, which might enable to avoid double imaging (radiographs + tomography) in patients for which a detailed osteoarticular assessment is required, with the advantage to obtain tomographic images in standing position and a reduction of radiation exposure.
Topics: Humans; Foot; Tomography, X-Ray Computed; Talipes Cavus; Weight-Bearing
PubMed: 37863530
DOI: 10.1016/j.fcl.2023.05.001 -
Journal of Veterinary Emergency and... 2023To assess the use of a standing position during abdominal point-of-care ultrasound (POCUS) examination when evaluating dogs for peritoneal effusion.
OBJECTIVE
To assess the use of a standing position during abdominal point-of-care ultrasound (POCUS) examination when evaluating dogs for peritoneal effusion.
DESIGN
Randomized prospective study over 17 months.
SETTING
Single-center, university veterinary teaching hospital.
ANIMALS
Thirty dogs presenting for acute abdominal disease. Eligibility included suspicion for free peritoneal effusion and the ability to stand.
INTERVENTIONS
Dogs underwent standing abdominal POCUS, right lateral abdominal POCUS, and a full abdominal ultrasound. We originally had nothing listed. It now includes all three ultrasound evaluations that were performed for each patient.
MEASUREMENTS AND MAIN RESULTS
Patients underwent both a right lateral and standing abdominal POCUS via a previously described abdominal focused assessment with sonography for trauma (A-FASTrl and A-FASTs, respectively) technique in a randomized and sequential order followed by a full abdominal ultrasound (AUS-full). The A-FASTs examination included a right flank location in addition to the following standard views: subxiphoid, left flank, urinary bladder, and umbilicus. Five-second cine loops were obtained at each location for each examination and reviewed in the order they were obtained. Locations for both A-FAST exams were interrogated in the same order every time. The cine loops were scored for the degree of peritoneal effusion based on a previously published abdominal fluid scoring system by a board-certified radiologist, radiology resident, and radiology intern. The overall abdominal fluid score (AFS) was compared to a subjective full abdominal ultrasound score given by a board-certified radiologist. Six dogs had no peritoneal effusion, 13 had a small volume (AFS 1 or 2), and 11 had a moderate to large volume (AFS 3 or 4). Excellent agreement (intraclass correlation coefficient) was found between the A-FASTs and A-FASTrl techniques (0.95, 0.93, 0.94), good agreement between A-FASTs and AUS-full (0.80, 0.77, 0.82), and good agreement between A-FASTrl and AUS-full (0.80, 0.82, 0.84). The interobserver agreement was good (0.87) for the A-FASTs technique and excellent (0.91) for the A-FASTrl technique. Mean observer agreement score was excellent (0.94) when evaluating A-FASTrl to A-FASTs, good (0.86) when evaluating A-FASTs to AUS-full, and good (0.87) when evaluating A-FASTrl to AUS-full.
CONCLUSION
Performing a standing abdominal POCUS examination may be a valid option for identifying and quantifying peritoneal effusion in situations when a more traditional right lateral approach cannot be performed.
Topics: Humans; Dogs; Animals; Point-of-Care Systems; Prospective Studies; Hospitals, Animal; Standing Position; Hospitals, Teaching; Ultrasonography
PubMed: 37573258
DOI: 10.1111/vec.13329 -
Heliyon Apr 2024Sagittal imbalance can be caused by various etiologies and is among the most important indicators of spinal deformity. Sagittal balance can be restored through surgical... (Review)
Review
BACKGROUND
Sagittal imbalance can be caused by various etiologies and is among the most important indicators of spinal deformity. Sagittal balance can be restored through surgical intervention based on several radiographic measures. The purpose of this study is to review the normal parameters in the sitting position, which are not well understood and could have significant implications for non-ambulatory patients.
METHODS
A systematic review was performed adhering to PRISMA Guidelines. Using R-software, the weighted means and 95% confidence intervals of the radiographic findings were calculated using a random effect model and significance testing using unpaired t-tests.
RESULTS
10 articles with a total of 1066 subjects reported radiographic measures of subjects with no spinal deformity in the sitting and standing position. In the healthy individual, standing sagittal vertical axis -16.8°was significantly less than sitting 28.4° (p < 0.0001), while standing lumbar lordosis 43.3°is significantly greater than sitting 21.3° (p < 0.0001). Thoracic kyphosis was not significantly different between the two groups (p = 0.368). Standing sacral slope 34.3° was significantly greater than sitting 19.5° (p < 0.0001) and standing pelvic tilt 14.0° was significantly less than sitting 33.9° (p < 0.0001).
CONCLUSIONS
There are key differences between standing and sitting postures, which could lead to undue stress on surgical implants and poor outcomes, especially for non-ambulatory populations. There is a need for more studies reporting sitting and standing radiographic measures in different postures and spinal conditions.
PubMed: 38590852
DOI: 10.1016/j.heliyon.2024.e28545 -
PloS One 2024Locomotion has been shown to impact aspects of visual processing in both humans and animal models. In the current study, we assess the impact of locomotion on the...
Locomotion has been shown to impact aspects of visual processing in both humans and animal models. In the current study, we assess the impact of locomotion on the dynamics of binocular rivalry. We presented orthogonal gratings, one contrast-modulating at 0.8 Hz (matching average step frequency) and the other at 3.2 Hz, to participants using a virtual reality headset. We compared two conditions: stationary and walking. We continuously monitored participants' foot position using tracking devices to measure the step cycle. During the walking condition, participants viewed the rivaling gratings for 60-second trials while walking on a circular path in a virtual reality environment. During the stationary condition, observers viewed the same stimuli and environment while standing still. The task was to continuously indicate the dominant percept via button press using handheld controllers. We found no significant differences between walking and standing for normalized dominance duration distributions, mean normalized dominance distributions, mean alternation rates, or mean fitted frequencies. Although our findings do not align with prior research highlighting distinctions in normalized dominance distributions between walking and standing, our study contributes unique evidence indicating that alternation rates vary across the step cycle. Specifically, we observed that the number of alternations is at its lowest during toe-off phases and reaches its peak at heel strike. This novel insight enhances our understanding of the dynamic nature of alternation patterns throughout the step cycle.
Topics: Humans; Vision, Binocular; Vision Disparity; Visual Perception; Walking; Virtual Reality; Photic Stimulation
PubMed: 38558003
DOI: 10.1371/journal.pone.0300222 -
Cureus Sep 2023Background There has been no report comparing shoulder kinematics and muscle activities during axial shoulder rotation in different positions. The purpose of this study...
Background There has been no report comparing shoulder kinematics and muscle activities during axial shoulder rotation in different positions. The purpose of this study was to investigate differences in shoulder kinematics and muscle activities during axial shoulder rotation in healthy subjects between standing and supine positions using three-dimensional/two-dimensional (3D/2D) registration techniques and electromyography (EMG). Methods Eleven healthy males agreed to participate in this study. We recorded the fluoroscopy time during active shoulder axial rotation with a 90° elbow flexion in both standing and supine positions, simultaneously recording surface EMG of the infraspinatus, anterior deltoid, posterior deltoid, and biceps brachii. Three-dimensional bone models were created from CT images, and shoulder kinematics were analyzed using 3D/2D registration techniques. Muscle activities were evaluated as a ratio of mean electromyographic values to 5-sec maximum voluntary isometric contractions. Results Scapular kinematics during axial shoulder rotation in the supine position showed similar patterns with those in the standing position. The scapula was more posteriorly tilted and more downwardly rotated in the supine posture than in standing (P < 0.001 for both). Acromiohumeral distance (AHD) in the supine posture was significantly larger than in standing. Muscle activities showed no significant differences between postures except for biceps (P < 0.001). Discussion Shoulder kinematics and muscle activities during axial rotation were similar in pattern between standing and supine postures, but there were shifts in scapular pose and AHD. The findings of this study suggest that posture may be an important consideration for the prescription of optimal shoulder therapy following surgery or for the treatment of shoulder disorders.
PubMed: 37900413
DOI: 10.7759/cureus.46154 -
Journal of Orthopaedic Surgery (Hong... 2023In order to simulate weight-bearing Computed Tomography (CT) examination, this study designed a simple stress position device. By analyzing the relevant data of stress...
BACKGROUND
In order to simulate weight-bearing Computed Tomography (CT) examination, this study designed a simple stress position device. By analyzing the relevant data of stress position footprints and weight-bearing position footprints, the feasibility of the stress position device to simulate standing weight-bearing was verified.
METHODS
This study randomly selected 25 volunteers for standing weight-bearing and stress position footprints collection, and measured the relevant indicators of stress position footprints and standing weight-bearing position footprints. Two foot and ankle surgeons conducted two measurements respectively on the footprints. Intra-observer and inter-observer reliability were calculated using intra-class correlation coefficients (ICC). Pearson correlation coefficient, ICC, scatter plot analysis, and paired -test were used to analyze the stress and weight-bearing position data.
RESULTS
The intra-observer and inter-observer measurement values were reliable. There was a certain degree of correlation between the stress position footprints and weight-bearing position footprints in terms of Pearson correlation coefficient, ICC, and scatter plot analysis. Paired t-tests showed significant differences in Clarke angle (t 2.636, .012), C-S index (t 10.568, .000), arch indx (t 2.176, .035), and arch lower angle (t 6.246, .000).
CONCLUSION
The stress position device can generate a certain degree of stress, and after further optimization and improvement of the stress position device, it is feasible to apply it to weight-bearing CT examination in clinical settings.
Topics: Humans; Feasibility Studies; Reproducibility of Results; Tomography, X-Ray Computed; Standing Position; Weight-Bearing
PubMed: 38061358
DOI: 10.1177/10225536231219976