Terrain Characterization Using Modified RANSAC Analysis of Human Gait Data

2012 ◽  
Author(s):  
Christopher Sullivan ◽  
Elizabeth A. DeBartolo ◽  
Kathleen Lamkin-Kennard
Keyword(s):  
Side Effects ◽  
Surface Profile ◽  
Lower Leg ◽  
Gait Pattern ◽  
Test Subject ◽  
Foot Drop ◽  
Human Gait ◽  
Post Stroke ◽  
The Many ◽  
Foot Orthotic

One of the many lasting side effects of a stroke can be foot drop, or an inability to dorsiflex the foot. In order to remedy this, many people wear an ankle-foot orthotic (AFO) post-stroke. One of the many troubles these individuals face is in dealing with obstacles such as stairs and ramps, because the AFO limits the plantarflexion that is natural in navigating these obstacles [1,2]. The end goal of this research is to create an active AFO that adapts to changing ground terrain, providing a more natural gait pattern. This paper presents the first part of this work: a means for identifying terrain in order to control an AFO. This has been accomplished using an infrared (IR) range sensor attached to the lower leg, used to measure the surface profile of the ground just ahead of a test subject. Using a modified RANSAC technique to fit experimental gait data, standardized gait profiles for different terrain have been quantified and shown to be reproducible, indicating the utility of the technique for terrain identification and AFO control.

A Wearable Gait Monitor and Terrain Prediction System

2013 ◽  
Author(s):  
Christopher Sullivan ◽  
Elizabeth DeBartolo ◽  
Kathleen Lamkin-Kennard
Keyword(s):  
Gait Pattern ◽  
Primary Diagnosis ◽  
Foot Drop ◽  
Prediction System ◽  
Prosthetic Device ◽  
Walking Activity ◽  
System 2 ◽  
The Many ◽  
Foot Orthotic ◽  
Difficulty Walking

Nearly one million people in 2009 were discharged from the hospital with stroke as the primary diagnosis [1]. One of the many lasting side effects of a stroke can be foot drop, or an inability to dorsiflex the foot. In order to remedy this, many people wear an ankle-foot orthotic (AFO) post-stroke. Interviews with AFO users revealed that they frequently have difficulty walking on stairs and ramps, because the AFO limits the plantarflexion that is natural in navigating those ground types. An active AFO that adapts to changing ground terrain would provide a more natural gait pattern for these individuals, if it could be designed to respond appropriately to upcoming terrain. In order to respond to terrain, the device must first identify the terrain. This paper outlines a system [2] that simultaneously predicts the type of terrain a user is approaching as they walk, and captures information about that user’s walking activity. Such a system can be used as the control system for an active orthotic or prosthetic device. Additionally, this system can be used as a stand-alone gait and terrain monitor to aid in rehabilitation monitoring in between patient visits with a clinician.

scholarly journals Persons post-stroke improve step length symmetry by walking asymmetrically

2020 ◽  
Author(s):  
Purnima Padmanabhan ◽  
Keerthana Sreekanth ◽  
Shivam Gulhar ◽  
Kendra M. Cherry-Allen ◽  
Kristan A. Leech ◽  
...  
Keyword(s):  
Center Of Mass ◽  
Metabolic Cost ◽  
Step Length ◽  
Gait Pattern ◽  
Future Research ◽  
Cost Of Transport ◽  
Post Stroke ◽  
Paretic Limb ◽  
Gait Parameters ◽  
The Many

Abstract Background Restoration of step length symmetry is a common rehabilitation goal after stroke. Persons post-stroke often retain the ability to walk with symmetric step lengths ("symmetric steps") at an elevated metabolic cost relative to healthy adults. Two key questions with direct implications for rehabilitation have emerged: 1) how do persons post-stroke generate symmetric steps, and 2) why do symmetric steps remain so effortful? Here, we aimed to understand how persons post-stroke generate symmetric steps and explored how the resulting gait pattern may relate to the metabolic cost of transport. Methods We recorded kinematic, kinetic, and metabolic data as nine persons post-stroke walked on an instrumented treadmill under two conditions: preferred walking and symmetric stepping (using visual feedback). Results Gait kinematics and kinetics remained markedly asymmetric even when persons post-stroke improved step length symmetry. Impaired paretic propulsion and abnormal movement of the center of mass were evident during both preferred walking and symmetric stepping. These deficits contributed to diminished positive work performed by the paretic limb on the center of mass in both conditions. Within each condition, decreased positive paretic work correlated with increased metabolic cost of transport and decreased walking speed across participants. Conclusions It is critical to consider the mechanics used to restore symmetric steps when designing interventions to improve walking after stroke. Future research should consider the many dimensions of asymmetry in post-stroke gait, and additional within-participant manipulations of gait parameters are needed to improve our understanding of the elevated metabolic cost of walking after stroke.

scholarly journals Persons post-stroke improve step length symmetry by walking asymmetrically

2020 ◽  
Author(s):  
Purnima Padmanabhan ◽  
Keerthana Sreekanth ◽  
Shivam Gulhar ◽  
Kendra M. Cherry-Allen ◽  
Kristan A. Leech ◽  
...  
Keyword(s):  
Center Of Mass ◽  
Metabolic Cost ◽  
Step Length ◽  
Gait Pattern ◽  
Future Research ◽  
Cost Of Transport ◽  
Post Stroke ◽  
Paretic Limb ◽  
Gait Parameters ◽  
The Many

Abstract Background Restoration of step length symmetry is a common rehabilitation goal after stroke. Persons post-stroke often retain the ability to walk with symmetric step lengths ("symmetric steps"); however, the resulting walking pattern remains effortful. Two key questions with direct implications for rehabilitation have emerged: 1) how do persons post-stroke generate symmetric steps, and 2) why do symmetric steps remain so effortful? Here, we aimed to understand how persons post-stroke generate symmetric steps and explored how the resulting gait pattern may relate to the metabolic cost of transport. Methods We recorded kinematic, kinetic, and metabolic data as nine persons post-stroke walked on an instrumented treadmill under two conditions: preferred walking and symmetric stepping (using visual feedback). Results Gait kinematics and kinetics remained markedly asymmetric even when persons post-stroke improved step length symmetry. Impaired paretic propulsion and aberrant movement of the center of mass were evident during both preferred walking and symmetric stepping. These deficits contributed to diminished positive work performed by the paretic limb on the center of mass in both conditions. Within each condition, decreased positive paretic work correlated with increased metabolic cost of transport and decreased walking speed across participants. Conclusions It is critical to consider the mechanics used to restore symmetric steps when designing interventions to improve walking after stroke. Future research should consider the many dimensions of asymmetry in post-stroke gait, and additional within-participant manipulations of gait parameters are needed to improve our understanding of the elevated metabolic cost of walking after stroke.

scholarly journals The Nanosystems Involved in Treating Lung Cancer

Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 682
Author(s):  
Andreea Crintea ◽  
Alina Gabriela Dutu ◽  
Gabriel Samasca ◽  
Ioan Alexandru Florian ◽  
Iulia Lupan ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Side Effects ◽  
Chromosomal Rearrangements ◽  
Sirna Delivery ◽  
Delivery Systems ◽  
Inorganic Nanoparticles ◽  
New Methods ◽  
Different Types ◽  
Or Gene ◽  
The Many

Even though there are various types of cancer, this pathology as a whole is considered the principal cause of death worldwide. Lung cancer is known as a heterogeneous condition, and it is apparent that genome modification presents a significant role in the occurrence of this disorder. There are conventional procedures that can be utilized against diverse cancer types, such as chemotherapy or radiotherapy, but they are hampered by the numerous side effects. Owing to the many adverse events observed in these therapies, it is imperative to continuously develop new and improved strategies for managing individuals with cancer. Nanomedicine plays an important role in establishing new methods for detecting chromosomal rearrangements and mutations for targeted chemotherapeutics or the local delivery of drugs via different types of nano-particle carriers to the lungs or other organs or areas of interest. Because of the complex signaling pathways involved in developing different types of cancer, the need to discover new methods for prevention and detection is crucial in producing gene delivery materials that exhibit the desired roles. Scientists have confirmed that nanotechnology-based procedures are more effective than conventional chemotherapy or radiotherapy, with minor side effects. Several nanoparticles, nanomaterials, and nanosystems have been studied, including liposomes, dendrimers, polymers, micelles, inorganic nanoparticles, such as gold nanoparticles or carbon nanotubes, and even siRNA delivery systems. The cytotoxicity of such nanosystems is a debatable concern, and nanotechnology-based delivery systems must be improved to increase the bioavailability, biocompatibility, and safety profiles, since these nanosystems boast a remarkable potential in many biomedical applications, including anti-tumor activity or gene therapy. In this review, the nanosystems involved in treating lung cancer and its associated challenges are discussed.

scholarly journals Biomechanical parameters characterising the foot during normal gait

2021 ◽  
Vol 21 (2) ◽  
pp. 87-104
Author(s):  
Arina SEUL ◽  
Aura MIHAI ◽  
Antonela CURTEZA ◽  
Mariana COSTEA ◽  
Bogdan SÂRGHIE
Keyword(s):  
Neuromuscular Control ◽  
Gait Pattern ◽  
Biomechanical Analysis ◽  
Human Gait ◽  
Foot Health ◽  
Mean Values ◽  
Study Results ◽  
Size Groups ◽  
Biomechanical Parameters ◽  
Extended Group

The biomechanical analysis allows to understand the normal and pathological gait, the mechanics of neuromuscular control, and last but not least, allows the visualisation of the effects of footwear on human gait or feet. Biomechanical analyses are very important for the footwear development process, as they can identify the incorrect loading of the foot or the incorrect gait pattern, thus avoiding the occurrence of deformations. This paper aims to create an average representative model of barefoot loading based on an extended group of participants by applying an optimal procedure for measuring biomechanical parameters. The variation of four basic biomechanical parameters, namely force, pressure, contact time and contact area, was measured using a pressure platform and a specialised software system. The data was collected from 32 healthy females, without particularities regarding foot health and the practice of performance sports, aged between 18 and 30 years, divided into three size groups – 36, 37 and 38. The T-Student test was applied to verify if there are significant differences between the left and right foot. Statistical indicators for each parameter were calculated, in order to characterize and establish the degree of variation of the obtained values, as follows: mean, standard deviation, minimum and maximum values, the amplitude of variation and coefficient of variation (CV). The study results confirm that the obtained mean values can be used as input data to load the foot and perform virtual simulations of footwear products.

scholarly journals Human Gait Cycle Analysis Using Kinect V2 Sensor

2020 ◽  
Vol 15 (3) ◽  
pp. 3-14
Author(s):  
Péter Müller ◽  
Ádám Schiffer
Keyword(s):  
Gait Cycle ◽  
Medical Condition ◽  
Measurement Data ◽  
Human Movement ◽  
Gait Pattern ◽  
Lower Limbs ◽  
Human Gait ◽  
Skeleton Model ◽  
Kinect V2 ◽  
Reduced Mobility

Examining a human movement can provide a wealth of information about a patient’s medical condition. The examination process can be used to diagnose abnormal changes (lesions), ability development and monitor the rehabilitation process of people with reduced mobility. There are several approaches to monitor people, among other things with sensors and various imaging and processing devices. In this case a Kinect V2 sensor and a self-developed LabView based application was used, to examine the movement of the lower limbs. The ideal gait pattern was recorded in the RoboGait training machine and the measured data was used to identify the phases of the human gait. During the evaluation, the position of the skeleton model, the associated body joints and angles can be calculated. The pre-recorded ideal and natural gait cycle can be compared.With the self-developed method the pre-recorded ideal and natural gait cycle can be compared and processed for further evaluation. The evaluated measurement data confirm that a reliable and mobile solution for gait analysis has been created.

scholarly journals LACK OF EMPHASIS ON PSYCHOLOGICAL REHABILITATION FOR STROKE PATIENTS

2012 ◽  
Vol 1 (1) ◽  
pp. 2
Author(s):  
Samina Masood Haider
Keyword(s):  
Emotional Difficulties ◽  
Stroke Survivors ◽  
Stroke Patients ◽  
Post Stroke ◽  
Post Stroke Depression ◽  
The Many ◽  
Over Time

It has been observed that most of the patients are not aware of the dilapidating affects of post stroke depression on their recovery, survival and a return to normal activities of life. The lack of emphasis on psychological rehabilitation for stroke patients is a source of concern for me and I would like to bring to your attention about the facts regarding the implications of proper psychological rehabilitation is not undertaken. Stroke survivors report a range of emotional difficulties, most common being fear, anxiety, frustration, anger, sadness and a sense of grief for their physical and mental losses. Usually these feelings may fade over time however, some patients may struggle with adjusting to the many changes following stroke. When this happens these feelings can develop into depression. It is estimated that approximately one-third of stroke1 survivors develop post-stroke depression (PSD)

scholarly journals A Dual-Learning Paradigm Simultaneously Improves Multiple Features of Gait Post-Stroke

2018 ◽  
Vol 32 (9) ◽  
pp. 810-820 ◽  
Author(s):  
Kendra M. Cherry-Allen ◽  
Matthew A. Statton ◽  
Pablo A. Celnik ◽  
Amy J. Bastian
Keyword(s):  
Knee Flexion ◽  
Joint Angle ◽  
Step Length ◽  
Learning Task ◽  
Gait Pattern ◽  
Learning Paradigm ◽  
Post Stroke ◽  
Learning Conditions ◽  
Hip Flexion ◽  
Gait Impairments

Background. Gait impairments after stroke arise from dysfunction of one or several features of the walking pattern. Traditional rehabilitation practice focuses on improving one component at a time, which may leave certain features unaddressed or prolong rehabilitation time. Recent work shows that neurologically intact adults can learn multiple movement components simultaneously. Objective. To determine whether a dual-learning paradigm, incorporating 2 distinct motor tasks, can simultaneously improve 2 impaired components of the gait pattern in people posttroke. Methods. Twelve individuals with stroke participated. Participants completed 2 sessions during which they received visual feedback reflecting paretic knee flexion during walking. During the learning phase of the experiment, an unseen offset was applied to this feedback, promoting increased paretic knee flexion. During the first session, this task was performed while walking on a split-belt treadmill intended to improve step length asymmetry. During the second session, it was performed during tied-belt walking. Results. The dual-learning task simultaneously increased paretic knee flexion and decreased step length asymmetry in the majority of people post-stroke. Split-belt treadmill walking did not significantly interfere with joint-angle learning: participants had similar rates and magnitudes of joint-angle learning during both single and dual-learning conditions. Participants also had significant changes in the amount of paretic hip flexion in both single and dual-learning conditions. Conclusions. People with stroke can perform a dual-learning paradigm and change 2 clinically relevant gait impairments in a single session. Long-term studies are needed to determine if this strategy can be used to efficiently and permanently alter multiple gait impairments.

Abstract TP101: Intra-arterial IL-1α is Well Tolerated and Neuroprotective After Experimental Ischemic Stroke

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Kathleen E Salmeron ◽  
Michael E Maniskas ◽  
Amanda Trout ◽  
Emmanuel Pinteaux ◽  
Justin F Fraser ◽  
...  
Keyword(s):  
Side Effects ◽  
Cortical Neurons ◽  
Glucose Deprivation ◽  
Cresyl Violet ◽  
Current Standard ◽  
Preclinical Research ◽  
Vessel Occlusion ◽  
Post Stroke ◽  
Primary Mouse

Endovascular thrombectomy and t-PA are the only current standard of care treatments for emergent large vessel occlusion (ELVO) stroke. Despite rising recanalization rates, stroke remains the leading cause of long-term disability worldwide suggesting that additional therapies are needed. Severe stroke morbidity may be due, in part, to the acute and sustained inflammatory stroke response. Preclinical research has supported anti-inflammatory agents in limiting brain injury and improving functional outcome; however, the post-stroke inflammatory cascade appears to have both beneficial and deleterious effects, necessitating careful therapeutic translation. We have recently demonstrated that delayed (3 day) post-stroke intravenous (IV) administration of the interleukin (IL)-1α (one of the two major isoforms of the pro-inflammatory family of cytokine IL-1), promoted, rather than suppressed, post-stroke angiogenesis in the transient middle cerebral artery occlusion (MCAo) mouse model. In this study, we aimed to show a therapeutic efficacy of IL-1α in neuroprotection. We investigated the potential for IL-1α, administered acutely IV or intra-arterial (IA) (n=5) after mouse MCAo, to also be neuroprotective. We noted that IV IL-1α (1 ng) is neuroprotective (as measured by cresyl violet stained infarct volumes) with mild, transient side effects (blunted hypertension and bradycardia) that were well tolerated, and with better functional recovery in free motion behavioral tests. IA IL-1α (0.1 ng) administration was even more neuroprotective without the systemic changes seen with IV treatment. Additionally, we noted that IL-1α is directly neuroprotective of primary mouse cortical neurons exposed to oxygen and glucose deprivation conditions in vitro . Taken together, these results suggest that IL-1α could be therapeutic after stroke when administered IV or IA, and the latter may eliminate potentially harmful hemodynamic side effects.

Application of Floquet Theory to Human Gait Kinematics and Dynamics

2021 ◽  
pp. 1-35
Author(s):  
Sandesh G. Bhat ◽  
Susheelkumar Cherangara Subramanian ◽  
Thomas S Sugar ◽  
Sangram Redkar
Keyword(s):  
Floquet Theory ◽  
Gait Pattern ◽  
Human Gait ◽  
Reduced Order ◽  
Oscillator System ◽  
Walking Gait ◽  
Gait Kinematics ◽  
Dimension Analysis ◽  
Time Trace ◽  
Original Domain

Abstract In this work, the lower extremity physiological parameters are recorded during normal walking gait, and the dynamical systems theory is applied towards its stability analysis. The human walking gait pattern of kinematic and dynamical data is approximated to periodic behavior. The embedding dimension analysis of the kinematic variable's time trace and use of Taken's theorem allows us to compute a reduced-order time series that retains the essential dynamics. In conjunction with Floquet Theory, this approach can help study the system's stability characteristics. The Lyapunov-Floquet (L-F) Transformation application results in constructing an invariant manifold resembling the form of a simple oscillator system. It is also demonstrated that the simple oscillator system, when re-mapped back to the original domain, reproduces the original system's time evolution (hip angle or knee angle, for example). A re-initialization procedure is suggested that improves the accuracy between the processed data and actual data. The theoretical framework proposed in this work is validated with the experiments using a motion capture system.

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