scholarly journals Measurement of Human Gait Symmetry using Body Surface Normals Extracted from Depth Maps

Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 891 ◽  
Author(s):  
Trong-Nguyen Nguyen ◽  
Huu-Hung Huynh ◽  
Jean Meunier
Keyword(s):  
Body Surface ◽  
Lower Limbs ◽  
Upper Body ◽  
Whole Body ◽  
Human Gait ◽  
Gait Symmetry ◽  
Symmetry Index ◽  
Depth Maps ◽  
Abnormal Gait ◽  
3D Information

In this paper, we introduce an approach for measuring human gait symmetry where the input is a sequence of depth maps of subject walking on a treadmill. Body surface normals are used to describe 3D information of the walking subject in each frame. Two different schemes for embedding the temporal factor into a symmetry index are proposed. Experiments on the whole body, as well as the lower limbs, were also considered to assess the usefulness of upper body information in this task. The potential of our method was demonstrated with a dataset of 97,200 depth maps of nine different walking gaits. An ROC analysis for abnormal gait detection gave the best result ( AUC = 0.958 ) compared with other related studies. The experimental results provided by our method confirm the contribution of upper body in gait analysis as well as the reliability of approximating average gait symmetry index without explicitly considering individual gait cycles for asymmetry detection.

Multi-Objective Optimization of Human Gait With a Discomfort Function

2016 ◽  
Author(s):  
Hyun-Jung Kwon ◽  
Hyun-Joon Chung ◽  
Yujiang Xiang
Keyword(s):  
Joint Torque ◽  
Upper Body ◽  
Whole Body ◽  
Human Gait ◽  
Multi Objective Optimization ◽  
Joint Angles ◽  
Backward Walking ◽  
Multi Objective ◽  
Body Model ◽  
Neutral Angle

The objective of this study was to develop a discomfort function for including a high DOF upper body model during walking. A multi-objective optimization (MOO) method was formulated by minimizing dynamic effort and the discomfort function simultaneously. The discomfort function is defined as the sum of the squares of deviation of joint angles from their neutral angle positions. The dynamic effort is the sum of the joint torque squared. To investigate the efficacy of the proposed MOO method, backward walking simulation was conducted. By minimizing both dynamic effort and the discomfort function, a 3D whole body model with a high DOF upper body for walking was demonstrated successfully.

scholarly journals Development of a Novel Fully Passive Treadmill Training Paradigm for Lower Limb Therapeutic Intervention

2013 ◽  
Vol 10 (2-3) ◽  
pp. 97-111
Author(s):  
M. Saiful Huq ◽  
M. O. Tokhi
Keyword(s):  
Gait Cycle ◽  
Mechanical Energy ◽  
Knee Extension ◽  
Treadmill Training ◽  
Lower Limbs ◽  
Upper Body ◽  
Whole Body ◽  
Software Environment ◽  
Joint Properties ◽  
Treadmill Belt

A simulation based study of a completely new form of body-weight supported treadmill training (BWSTT) technique which is fully passive in nature is presented in this paper. The approach does not require any powered means at the lower limbs and is implemented using a combination of coordinated joint locking/unlocking and flexible torque transfer mechanisms. The hip extension pertaining to the stance phase of the gait cycle is achieved through the stance foot being literally dragged by the treadmill belt while the required manoeuvring of the trunk is expected to be accomplished by the voluntary arm-support from the subject. The swing phase, on the other hand, is initiated through appropriately coupling the swing knee with the contralateral extending hip and eventually achieve full knee extension through switching the treadmill speed to a lower value. Considering adequate support from the able arms, the process effectively turns the frictional force at the foot-treadmill belt interface into an agent causing the required whole body mechanical energy fluctuation during the gait cycle.The simulation platform consists of a dynamic planer (sagittal) full body humanoid model along with the treadmill model developed within a CAD based software environment interfaced with passive viscoelastic joint properties implemented in Simulink. The voluntary upper body effort as well as control of the gait cycle are also developed within MATLAB/Simulink environment. The gait cycle generated using the new concept is thoroughly investigated through this simulation study.

scholarly journals Effect of Seat Backrest Inclination on the Muscular Pattern and Biomechanical Parameters of the Sit-to-Stand

2021 ◽  
Vol 15 ◽  
Author(s):  
Nadège Tebbache ◽  
Alain Hamaoui
Keyword(s):  
Kinematic Chain ◽  
The Body ◽  
Activity Level ◽  
Lower Limbs ◽  
Upper Body ◽  
Whole Body ◽  
Activity Levels ◽  
Phase Duration ◽  
Sit To Stand ◽  
Biomechanical Parameters

Objectives: The sit-to-stand (STS) transfer mobilizes an extended part of the kinematic chain throughout a postural phase characterized by a flexion of the trunk and a focal phase consisting of a whole-body extension. The aim of this study was to analyze the variations of the global muscular pattern and the biomechanical parameters in both phases, in relation with seat backrest inclination.Methods: Fifteen participants were asked to stand up from a seat with 5 backrest inclination settings and at 2 execution speeds. The ground reaction forces and the activity levels of fifteen muscles of the trunk and lower limbs were investigated.Results: Backrest-induced modifications were mainly observed in the postural phase: inclining the backrest backward increased the phase duration and the activity level of the sternocleidomastoideus and the rectus abdominis, while it reduced the activity of the tibialis anterior. It also allowed for an increased maximal anteroposterior velocity of the body center of mass. Higher execution speed led to increased and earlier muscular activities of many trunk and lower limbs muscles, predominantly in the postural phase.Discussion: Taken together, these results suggest that a greater backrest inclination increases the demand in the postural phase due to the increase of the upper body gravity torque about the ischial tuberosities, and requires an adaptation of muscular activity levels and timing, but with the same overall pattern. The kinetic energy gained during the longer excursion of the trunk may also require less activation of the lower limbs muscles involved in the generation of propulsive forces of the body.

Mid-aortic syndrome: computed tomography angiography depicting extensive collateral circulation in an 11-year-old patient with thoracoabdominal aortic coarctation

VASA ◽  
2012 ◽  
Vol 41 (2) ◽  
pp. 132-135 ◽  
Author(s):  
Krohn ◽  
Gebauer ◽  
Hübler ◽  
Beck
Keyword(s):  
Computed Tomography ◽  
Computed Tomography Angiography ◽  
Collateral Circulation ◽  
Intestinal Ischemia ◽  
Clinical Presentation ◽  
Lower Limbs ◽  
Upper Body ◽  
Descending Aorta ◽  
Before And After ◽  
Blood Pressures

The mid-aortic syndrome is an uncommon clinical condition characterized by severe narrowing of the descending aorta, usually with involvement of its renal and visceral branches, presenting with uncontrollably elevated blood pressures of the upper body, renal and cardiac failure, intestinal ischemia, encephalopathy symptoms and claudication of the lower limbs, although clinical presentation is variable. In this article we report the case of an eleven-year-old patient with the initial diagnosis of a mid-aortic syndrome and present the computed tomography angiography pictures and reconstructions before and after surgical therapy.

Congenital Syphilis Simulating Bone Neoplasm in 2-Month Old Infant – Case Report

2017 ◽  
Vol 2 (1) ◽  
Keyword(s):  
Case Report ◽  
Congenital Syphilis ◽  
Eosinophilic Granuloma ◽  
Osteolytic Lesion ◽  
Lower Limbs ◽  
Upper Body ◽  
Elective Cesarean Section ◽  
Distal Fibula ◽  
X Ray

Introduction: Congenital Syphilis (CS) occurs through the transplacental transmission of Treponema pallidum in inadequately treated or non-treated pregnant women, and is capable of severe consequences such as miscarriage, preterm birth, congenital disease and/or neonatal death. CS has been showing an increasing incidence worldwide, with an increase of 208% from 2009 to 2015 in Brazil. Case report: 2-month old infant receives care in emergency service due to edema of right lower limb with pain in mobilization. X-ray with osteolytic lesion in distal fibula. Infant was sent to the Pediatrics Oncology clinic. Perinatal data: 7 prenatal appointments, negative serology at 10 and 30 weeks of gestation. End of pregnancy tests were not examined and tests for mother’s hospital admission were not requested. Mother undergone elective cesarean section at 38 weeks without complications. During the pediatric oncologist appointment, patient showed erythematous-squamous lesions in neck and other scar-like lesions in upper body. A new X-ray of lower limbs showed lesions in right fibula with periosteal reaction associated with aggressive osteolytic lesion compromising distal diaphysis, with cortical bone rupture and signs of pathological fracture, suggestive of eosinophilic granuloma. She was hospitalized for a lesion biopsy. Laboratory tests: hematocrit: 23.1 / hemoglobin 7.7 / leukocytes 10,130 (without left deviation) / platelets 638,000 / Negative Cytomegalovirus IgG and IgM and Toxoplasmosis IgG and IgM / VDRL 1:128. Congenital syphilis diagnosis with skin lesions, bone alterations and anemia. Lumbar puncture: glucose 55 / total proteins 26 / VDRL non reagent / 13 leukocytes (8% neutrophils; 84% monomorphonuclear; 8% macrophages) and 160 erythrocytes / negative VDRL and culture. X-ray of other long bones, ophthalmological evaluation and abdominal ultrasound without alterations. Patient was hospitalized for 14 days for treatment with Ceftriaxone 100mg/kg/day, due to the lack of Crystalline Penicillin in the hospital. She is now under outpatient follow-up. Discussion: CS is responsible for high rates of morbidity and mortality. The ongoing increase of cases of this pathology reflects a severe health issue and indicates failures in policies for the prevention of sexually transmitted diseases, with inadequate follow-up of prenatal and maternity protocols.

scholarly journals Diagnostic Value of Whole-Body MRI Short Protocols in Bone Lesion Detection in Multiple Myeloma Patients

Diagnostics ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1053
Author(s):  
Davide Ippolito ◽  
Teresa Giandola ◽  
Cesare Maino ◽  
Davide Gandola ◽  
Maria Ragusi ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow Involvement ◽  
Bone Lesion ◽  
Diagnostic Value ◽  
Lesion Detection ◽  
Lower Limbs ◽  
Whole Body ◽  
Bone Lesions ◽  
Whole Body Mri ◽  
Mri Protocol

The aim of the study is to evaluate the effectiveness of short whole-body magnetic resonance imaging (WBMRI) protocols for the overall assessment of bone marrow involvement in patients with multiple myeloma (MM), in comparison with standard whole-body MRI protocol. Patients with biopsy-proven MM, who underwent a WBMRI with full-body coverage (from vertex to feet) were retrospectively enrolled. WBMRI images were independently evaluated by two expert radiologists, in terms of infiltration patterns (normal, focal, diffuse, and combined), according to location (the whole skeleton was divided into six anatomic districts: skull, spine, sternum and ribs, upper limbs, pelvis and proximal two-thirds of the femur, remaining parts of lower limbs) and lytic lesions number (<5, 5–20, and >20). The majority of patients showed focal and combined infiltration patterns with bone lesions predominantly distributed in the spine and pelvis. As skull and lower limbs are less frequently involved by focal bone lesions, excluding them from the standard MRI protocol allows to obtain a shorter protocol, maintaining a good diagnostic value.

scholarly journals Acute effect of high-definition and conventional tDCS on exercise performance and psychophysiological responses in endurance athletes: a randomized controlled trial

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniel Gomes da Silva Machado ◽  
Marom Bikson ◽  
Abhishek Datta ◽  
Egas Caparelli-Dáquer ◽  
Gozde Unal ◽  
...  
Keyword(s):  
Exercise Performance ◽  
Controlled Trial ◽  
Lower Limbs ◽  
Endurance Athletes ◽  
Test Reliability ◽  
Whole Body ◽  
Time To Exhaustion ◽  
Small Ring ◽  
High Definition ◽  
Psychophysiological Responses

AbstractTranscranial direct current stimulation (tDCS) has been used aiming to boost exercise performance and inconsistent findings have been reported. One possible explanation is related to the limitations of the so-called “conventional” tDCS, which uses large rectangular electrodes, resulting in a diffuse electric field. A new tDCS technique called high-definition tDCS (HD-tDCS) has been recently developed. HD-tDCS uses small ring electrodes and produces improved focality and greater magnitude of its aftereffects. This study tested whether HD-tDCS would improve exercise performance to a greater extent than conventional tDCS. Twelve endurance athletes (29.4 ± 7.3 years; 60.15 ± 5.09 ml kg−1 min−1) were enrolled in this single-center, randomized, crossover, and sham-controlled trial. To test reliability, participants performed two time to exhaustion (TTE) tests (control conditions) on a cycle simulator with 80% of peak power until volitional exhaustion. Next, they randomly received HD-tDCS (2.4 mA), conventional (2.0 mA), or active sham tDCS (2.0 mA) over the motor cortex for 20-min before performing the TTE test. TTE, heart rate (HR), associative thoughts, peripheral (lower limbs), and whole-body ratings of perceived exertion (RPE) were recorded every minute. Outcome measures were reliable. There was no difference in TTE between HD-tDCS (853.1 ± 288.6 s), simulated conventional (827.8 ± 278.7 s), sham (794.3 ± 271.2 s), or control conditions (TTE1 = 751.1 ± 261.6 s or TTE2 = 770.8 ± 250.6 s) [F(1.95; 21.4) = 1.537; P = 0.24; η2p = 0.123]. There was no effect on peripheral or whole-body RPE and associative thoughts (P > 0.05). No serious adverse effect was reported. A single session of neither HD-tDCS nor conventional tDCS changed exercise performance and psychophysiological responses in athletes, suggesting that a ceiling effect may exist.

scholarly journals A Feasibility Study of Kinematic Characteristics on the Upper Body According to the Shooting of Elite Disabled Archery Athletes

2021 ◽  
Vol 18 (6) ◽  
pp. 2962
Author(s):  
Tae-Whan Kim ◽  
Jae-Won Lee ◽  
Seoung-Ki Kang ◽  
Kyu-Yeon Chae ◽  
Sang-Hyup Choi ◽  
...  
Keyword(s):  
The Body ◽  
Lower Limbs ◽  
Upper Body ◽  
Movement Trajectory ◽  
Phase 2 ◽  
Kinematic Characteristics ◽  
Significant Difference ◽  
Athletes With Disabilities ◽  
Body Center ◽  
Time Required

The purpose of this study is to compare and analyze the kinematic characteristics of the upper limb segments during the archery shooting of Paralympic Wheelchair Class archers (ARW2—second wheelchair class—paraplegia or comparable disability) and Paralympic Standing Class archers (ARST—standing archery class—loss of 25 points in the upper limbs or lower limbs), where archers are classified according to their disability grade among elite disabled archers. The participants of this study were selected as seven elite athletes with disabilities by the ARW2 (n = 4) and ARST (n = 3). The analysis variables were (1) the time required for each phase, (2) the angle of inclination of the body center, (3) the change of trajectory of body center, and (4) the change of the movement trajectory of the bow center by phase when performing six shots in total. The ARW2 group (drawing phase; M = 2.228 s, p < 0.05, holding phase; M = 4.414 s, p < 0.05) showed a longer time than the ARST group (drawing phase; M = 0.985 s, holding phase; M = 3.042 s), and the angle of the body did not show a significant difference between the two groups. Additionally, in the direction of the anteroposterior axis in the drawing phase, the change in the movement trajectory of the body center showed a more significant amount of change in the ARW2 group than in the ARST group, and the change in the movement trajectory of the bow center did not show a significant difference between the two groups.

scholarly journals Spatio-temporal gait parameters obtained from foot-worn inertial sensors are reliable in healthy adults in single- and dual-task conditions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
J. Soulard ◽  
J. Vaillant ◽  
R. Balaguier ◽  
N. Vuillerme
Keyword(s):  
Dual Task ◽  
Inertial Sensors ◽  
Healthy Adults ◽  
Gait Symmetry ◽  
Symmetry Index ◽  
Task Effects ◽  
Gait Parameters ◽  
Task Conditions ◽  
Healthy Participants ◽  
Absolute Reliability

AbstractInertial measurement units (IMUs) are increasingly popular and may be usable in clinical routine to assess gait. However, assessing their intra-session reliability is crucial and has not been tested with foot-worn sensors in healthy participants. The aim of this study was to assess the intra-session reliability of foot-worn IMUs for measuring gait parameters in healthy adults. Twenty healthy participants were enrolled in the study and performed the 10-m walk test in single- and dual-task ('carrying a full cup of water') conditions, three trials per condition. IMUs were used to assess spatiotemporal gait parameters, gait symmetry parameters (symmetry index (SI) and symmetry ratio (SR)), and dual task effects parameters. The relative and the absolute reliability were calculated for each gait parameter. Results showed that spatiotemporal gait parameters measured with foot-worn inertial sensors were reliable; symmetry gait parameters relative reliability was low, and SR showed better absolute reliability than SI; dual task effects were poorly reliable, and taking the mean of the second and the third trials was the most reliable. Foot-worn IMUs are reliable to assess spatiotemporal and symmetry ratio gait parameters but symmetry index and DTE gait parameters reliabilities were low and need to be interpreted with cautious by clinicians and researchers.

Whole Body Surface Assessment – Implementierung und Erfahrungen von 360° 3D Ganzkörperscans: Möglichkeiten zur Objektivierung und Verlaufskontrolle an den Extremitäten und am Körperstamm

2019 ◽  
Vol 51 (04) ◽  
pp. 240-248
Author(s):  
Lucas Etzel ◽  
Konstantin Christoph Koban ◽  
Zhouxiao Li ◽  
Konstantin Frank ◽  
Riccardo Enzo Giunta ◽  
...  
Keyword(s):  
Body Surface ◽  
Whole Body ◽  
Surface Assessment

Zusammenfassung Hintergrund Dreidimensionale (3D) Oberflächenaufnahmen haben sich als objektiver Mehrwert in der Planung und Dokumentation unterschiedlicher plastisch chirurgischer Eingriffe erwiesen. Obwohl Oberflächen- und Volumenanalysen für einzelne Bereiche wie der Brust und des Gesichts im klinischen Alltag eingesetzt werden, war es bislang nicht ausreichend möglich, Auswirkungen auf die gesamte Körperoberfläche zu erfassen und zu quantifizieren. Ziel dieser Studie war die Implementierung von 360° Ganzkörperscans zur zukünftigen Therapie-Evaluierung beim Lipödem. Patienten, Material und Methoden Drei unterschiedliche 3D Oberflächenscanner (Eva, Thor und Sense) wurden am Probanden hinsichtlich ihrer Reproduzierbarkeit und Präzision für 360° Aufnahmen evaluiert. Unter einem standardisierten Setting bestehend aus einem automatischen Drehteller und definierten Posen wurden axiale Umfangsmessungen und schichtweise Volumina bestimmt. Statistische und klinische relevante Abweichungen wurden untersucht. Ergebnisse Ein standardisierter 360° Scan Ablauf wurde implementiert. Die Reproduzierbarkeit aller Scanner war zufriedenstellend (p > 0,05). Es zeigten sich vergleichbare axiale Umfangsmessungen und Volumina für den Eva und Thor Scanner (p > 0,05). Der Sense Scanner erreichte eine ausreichende Messgenauigkeit im Thoraxbereich, jedoch signifikante Abweichungen an der unteren Extremität (p < 0,05). Die Datenauswertung konnte auf ausgewählte klinische Beispiele übertragen werden. Schlussfolgerung Es konnte erfolgreich eine 360° Oberflächenaufnahmetechnik und Analyse in der Plastischen Chirurgie eingeführt werden. Zwei der getesteten Geräte ermöglichen objektive Umfangs- und Volumenmessungen am gesamten Körper. Das dritte Gerät, der günstige Sense Scanner, ermöglichte zwar 360° Aufnahmen, jedoch war dessen Präzision nicht für alle Bereiche ausreichend. In Zukunft könnten somit die Auswirkungen unterschiedlicher Therapien an der gesamten Körperoberfläche evaluiert werden.

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