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Zhou J, Mao Q, Yang F, Zhang J, Shi M, Hu Z. Development and Assessment of Artificial Intelligence-Empowered Gait Monitoring System Using Single Inertial Sensor. SENSORS (BASEL, SWITZERLAND) 2024; 24:5998. [PMID: 39338743 PMCID: PMC11436140 DOI: 10.3390/s24185998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2024] [Revised: 09/12/2024] [Accepted: 09/13/2024] [Indexed: 09/30/2024]
Abstract
Gait instability is critical in medicine and healthcare, as it has associations with balance disorder and physical impairment. With the development of sensor technology, despite the fact that numerous wearable gait detection and recognition systems have been designed to monitor users' gait patterns, they commonly spend a lot of time and effort to extract gait metrics from signal data. This study aims to design an artificial intelligence-empowered and economic-friendly gait monitoring system. A pair of intelligent shoes with a single inertial sensor and a smartphone application were developed as a gait monitoring system to detect users' gait cycle, stand phase time, swing phase time, stride length, and foot clearance. We recruited 30 participants (24.09 ± 1.89 years) to collect gait data and used the Vicon motion capture system to verify the accuracy of the gait metrics. The results show that the gait monitoring system performs better on the assessment of the gait metrics. The accuracy of stride length and foot clearance is 96.17% and 92.07%, respectively. The artificial intelligence-empowered gait monitoring system holds promising potential for improving gait analysis and monitoring in the medical and healthcare fields.
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Affiliation(s)
- Jie Zhou
- School of Apparel and Art Design, Xi'an Polytechnic University, No. 19 Jinhua South Road, Xi'an 710048, China
| | - Qian Mao
- School of Design, The Hong Kong Polytechnic University, Hong Kong, China
| | - Fan Yang
- Department of Electrical and Electronic Engineering, The Hong Kong Polytechnic University, Hong Kong, China
| | - Jun Zhang
- School of Fashion and Textiles, The Hong Kong Polytechnic University, Hong Kong, China
| | - Menghan Shi
- Lancaster Imagination Lab, Lancashire, Lancaster LA1 4YD, UK
| | - Zilin Hu
- School of Design, South China University of Technology, Guangzhou 510641, China
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2
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Gibson E, Douglas G, Jeffries K, Delaurier J, Chestnut T, Charlton JM. Foot orientation and trajectory variability in locomotion: Effects of real-world terrain. PLoS One 2024; 19:e0293691. [PMID: 38753603 PMCID: PMC11098422 DOI: 10.1371/journal.pone.0293691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 03/20/2024] [Indexed: 05/18/2024] Open
Abstract
Capturing human locomotion in nearly any environment or context is becoming increasingly feasible with wearable sensors, giving access to commonly encountered walking conditions. While important in expanding our understanding of locomotor biomechanics, these more variable environments present challenges to identify changes in data due to person-level factors among the varying environment-level factors. Our study examined foot-specific biomechanics while walking on terrain commonly encountered with the goal of understanding the extent to which these variables change due to terrain. We recruited healthy adults to walk at self-selected speeds on stairs, flat ground, and both shallow and steep sloped terrain. A pair of inertial measurement units were embedded in both shoes to capture foot biomechanics while walking. Foot orientation was calculated using a strapdown procedure and foot trajectory was determined by double integrating the linear acceleration. Stance time, swing time, cadence, sagittal and frontal orientations, stride length and width were extracted as discrete variables. These data were compared within-participant and across terrain conditions. The physical constraints of the stairs resulted in shorter stride lengths, less time spent in swing, toe-first foot contact, and higher variability during stair ascent specifically (p<0.05). Stride lengths increased when ascending compared to descending slopes, and the sagittal foot angle at initial contact was greatest in the steep slope descent condition (p<0.05). No differences were found between conditions for horizontal foot angle in midstance (p≥0.067). Our results show that walking on slopes creates differential changes in foot biomechanics depending on whether one is descending or ascending, and stairs require different biomechanics and gait timing than slopes or flat ground. This may be an important factor to consider when making comparisons of real-world walking bouts, as greater proportions of one terrain feature in a data set could create bias in the outcomes. Classifying terrain in unsupervised walking datasets would be helpful to avoid comparing metrics from different walking terrain scenarios.
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Affiliation(s)
- Emma Gibson
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - Greg Douglas
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - Katelyn Jeffries
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - Julianne Delaurier
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - Taylor Chestnut
- Department of Physical Therapy, University of British Columbia, Vancouver, BC, Canada
| | - Jesse M. Charlton
- School of Kinesiology, University of British Columbia, Vancouver, BC, Canada
- School of Biomedical Engineering, University of British Columbia, Vancouver, BC, Canada
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Calvano A, Kleinholdermann U, Heun AS, Bopp MHA, Nimsky C, Timmermann L, Pedrosa DJ. Structural connectivity of low-frequency subthalamic stimulation for improving stride length in Parkinson's disease. Neuroimage Clin 2024; 42:103591. [PMID: 38507954 PMCID: PMC10965492 DOI: 10.1016/j.nicl.2024.103591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 03/07/2024] [Accepted: 03/13/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND A reduction in stride length is considered a key characteristic of gait kinematics in Parkinson's disease (PD) and has been identified as a predictor of falls. Although low-frequency stimulation (LFS) has been suggested as a method to improve gait characteristics, the underlying structural network is not well understood. OBJECTIVE This study aims to investigate the structural correlates of changes in stride length during LFS (85 Hz). METHODS Objective gait performance was retrospectively evaluated in 19 PD patients who underwent deep brain stimulation (DBS) at 85 Hz and 130 Hz. Individual DBS contacts and volumes of activated tissue (VAT) were computed using preoperative magnetic resonance imaging (MRI) and postoperative computed tomography (CT) scans. Structural connectivity profiles to predetermined cortical and mesencephalic areas were estimated using a normative connectome. RESULTS LFS led to a significant improvement in stride length compared to 130 Hz stimulation. The intersection between VAT and the associative subregion of the subthalamic nucleus (STN) was associated with an improvement in stride length and had structural connections to the supplementary motor area, prefrontal cortex, and pedunculopontine nucleus. Conversely, we found that a lack of improvement was linked to stimulation volumes connected to cortico-diencephalic fibers bypassing the STN dorsolaterally. The robustness of the connectivity model was verified through leave-one-patient-out, 5-, and 10-fold cross cross-validation paradigms. CONCLUSION These findings offer new insights into the structural connectivity that underlies gait changes following LFS. Targeting the non-motor subregion of the STN with LFS on an individual level may present a potential therapeutic approach for PD patients with gait disorders.
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Affiliation(s)
- Alexander Calvano
- Department of Neurology, Philipps-University Marburg, Marburg, Germany
| | - Urs Kleinholdermann
- Department of Neurology, Philipps-University Marburg, Marburg, Germany; Center of Mind, Brain and Behaviour, Philipps-University Marburg, Marburg, Germany
| | | | - Miriam H A Bopp
- Center of Mind, Brain and Behaviour, Philipps-University Marburg, Marburg, Germany; Department of Neurosurgery, Philipps-University Marburg, Marburg, Germany
| | - Christopher Nimsky
- Center of Mind, Brain and Behaviour, Philipps-University Marburg, Marburg, Germany; Department of Neurosurgery, Philipps-University Marburg, Marburg, Germany
| | - Lars Timmermann
- Department of Neurology, Philipps-University Marburg, Marburg, Germany; Center of Mind, Brain and Behaviour, Philipps-University Marburg, Marburg, Germany
| | - David J Pedrosa
- Department of Neurology, Philipps-University Marburg, Marburg, Germany; Center of Mind, Brain and Behaviour, Philipps-University Marburg, Marburg, Germany.
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Reinhardt L, Schwesig R, Schulze S, Donath L, Kurz E. Accuracy of unilateral and bilateral gait assessment using a mobile gait analysis system at different walking speeds. Gait Posture 2024; 109:291-297. [PMID: 38387196 DOI: 10.1016/j.gaitpost.2024.01.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Revised: 12/24/2023] [Accepted: 01/22/2024] [Indexed: 02/24/2024]
Abstract
BACKGROUND Previous research on the accuracy of mobile measurement systems has focused on parameters related to the whole gait cycle. Specifically, bilateral gait characteristics were primarily used as outcome measures. RESEARCH QUESTION How accurate are unilateral gait characteristics detected using a mobile system at various fixed walking speeds? METHODS Gait analysis during treadmill walking at velocities (VEL) of 2.5 (v1), 4.5 (v2) and 6.5 km/h (v3) was performed in a population of 47 healthy young adults, consisting of 27 females (age: 23 ± 2 years, BMI: 21.4 ± 2.2 kg/m²) and 20 males (age: 22 ± 1 years, BMI: 23.3 ± 3.4 kg/m²). Spatiotemporal gait data were simultaneously determined using an instrumented treadmill (gaitway 3D) and a mobile gait analysis system (RehaGait). Besides VEL, bilateral (stride length [SL], cadence [CAD]) and unilateral (contact duration [CON], single [SS] and double support duration [DS]) outcomes were validated. RESULTS Across the three VEL investigated, the correlations between both measurement systems were almost perfect in SL and CAD (r > 0.97). In addition, SL significantly differed (p < 0.01) with moderate to large effects, whereby the root mean squared error (RMSE) did not exceed 1.8 cm. RMSE in CAD was not higher than 0.33 spm and statistically significant differences were only present at v1 (d = 0.63). DS was the most erroneous unilateral parameter with values for %RMSE ranging from 9% at v1 to 14% at v3. In CON and SS %RMSE was in a magnitude of 2-4% across all VEL. Furthermore, VEL affected measurement accuracy in unilateral outcomes with moderate to large effects (F (2, 45) > 6.0, p < 0.01, ηp2 > 0.11) with consistently higher differences at lower velocities. SIGNIFICANCE Based on the results presented the validity of the mobile gait analysis system investigated to detect gait asymmetries must be questioned.
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Affiliation(s)
- Lars Reinhardt
- Institute for Applied Training Science, Leipzig, Germany.
| | - René Schwesig
- Department of Orthopedic and Trauma Surgery, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Stephan Schulze
- Department of Orthopedic and Trauma Surgery, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Lars Donath
- Department of Intervention Research in Exercise Training, German Sport University Cologne, Cologne, Germany
| | - Eduard Kurz
- Department of Orthopedic and Trauma Surgery, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
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Jocham AJ, Laidig D, Guggenberger B, Seel T. Measuring highly accurate foot position and angle trajectories with foot-mounted IMUs in clinical practice. Gait Posture 2024; 108:63-69. [PMID: 37988888 DOI: 10.1016/j.gaitpost.2023.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 10/19/2023] [Accepted: 11/01/2023] [Indexed: 11/23/2023]
Abstract
BACKGROUND Gait analysis using foot-mounted IMUs is a promising method to acquire gait parameters outside of laboratory settings and in everyday clinical practice. However, the need for precise sensor attachment or calibration, the requirement of environments with a homogeneous magnetic field, and the limited applicability to pathological gait patterns still pose challenges. Furthermore, in previously published work, the measurement accuracy of such systems is often only validated for specific points in time or in a single plane. RESEARCH QUESTION This study investigates the measurement accuracy of a gait analysis method based on foot-mounted IMUs in the acquisition of the foot motion, i.e., position and angle trajectories of the foot in the sagittal, frontal, and transversal plane over the entire gait cycle. RESULTS A comparison of the proposed method with an optical motion capture system showed an average RMSE of 0.67° for pitch, 0.63° for roll and 1.17° for yaw. For position trajectories, an average RMSE of 0.51 cm for vertical lift and 0.34 cm for lateral shift was found. The measurement error of the IMU-based method is found to be much smaller than the deviations caused by the shoes. SIGNIFICANCE The proposed method is found to be sufficiently accurate for clinical practice. It does not require precise mounting, special calibration movements, or magnetometer data, and shows no difference in measurement accuracy between normal and pathological gait. Therefore, it provides an easy-to-use alternative to optical motion capture and facilitates gait analysis independent of laboratory settings.
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Affiliation(s)
- Andreas J Jocham
- Institute of Physiotherapy, FH JOANNEUM University of Applied Sciences, Graz, Austria.
| | - Daniel Laidig
- Control Systems Group, Technische Universität Berlin, Berlin, Germany
| | - Bernhard Guggenberger
- Institute of Physiotherapy, FH JOANNEUM University of Applied Sciences, Graz, Austria; Department of Orthopaedics and Trauma, Medical University of Graz, Graz, Austria
| | - Thomas Seel
- Institute of Mechatronic Systems, Leibniz Universität Hannover, Hannover, Germany
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Küderle A, Ullrich M, Roth N, Ollenschläger M, Ibrahim AA, Moradi H, Richer R, Seifer AK, Zürl M, Sîmpetru RC, Herzer L, Prossel D, Kluge F, Eskofier BM. Gaitmap-An Open Ecosystem for IMU-Based Human Gait Analysis and Algorithm Benchmarking. IEEE OPEN JOURNAL OF ENGINEERING IN MEDICINE AND BIOLOGY 2024; 5:163-172. [PMID: 38487091 PMCID: PMC10939318 DOI: 10.1109/ojemb.2024.3356791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 11/15/2023] [Accepted: 01/17/2024] [Indexed: 03/17/2024] Open
Abstract
Goal: Gait analysis using inertial measurement units (IMUs) has emerged as a promising method for monitoring movement disorders. However, the lack of public data and easy-to-use open-source algorithms hinders method comparison and clinical application development. To address these challenges, this publication introduces the gaitmap ecosystem, a comprehensive set of open source Python packages for gait analysis using foot-worn IMUs. Methods: This initial release includes over 20 state-of-the-art algorithms, enables easy access to seven datasets, and provides eight benchmark challenges with reference implementations. Together with its extensive documentation and tooling, it enables rapid development and validation of new algorithm and provides a foundation for novel clinical applications. Conclusion: The published software projects represent a pioneering effort to establish an open-source ecosystem for IMU-based gait analysis. We believe that this work can democratize the access to high-quality algorithm and serve as a driver for open and reproducible research in the field of human gait analysis and beyond.
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Affiliation(s)
- Arne Küderle
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Martin Ullrich
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Nils Roth
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Malte Ollenschläger
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Alzhraa A. Ibrahim
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
- Department of Molecular NeurologyFAU Erlangen91054ErlangenGermany
- Computer Science Department, Faculty of Computers and InformationAssiut UniversityAssiut Governorate71515Egypt
| | - Hamid Moradi
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Robert Richer
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Ann-Kristin Seifer
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Matthias Zürl
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Raul C. Sîmpetru
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Liv Herzer
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Dominik Prossel
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Felix Kluge
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
| | - Bjoern M. Eskofier
- Machine Learning and Data Analytics LabFriedrich-Alexander Universität Erlangen-Nürnberg (FAU)91054ErlangenGermany
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Mügge F, Kleinholdermann U, Heun A, Ollenschläger M, Hannink J, Pedrosa DJ. Subthalamic 85 Hz deep brain stimulation improves walking pace and stride length in Parkinson's disease patients. Neurol Res Pract 2023; 5:33. [PMID: 37559161 PMCID: PMC10413698 DOI: 10.1186/s42466-023-00263-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 06/23/2023] [Indexed: 08/11/2023] Open
Abstract
BACKGROUND Mobile gait sensors represent a compelling tool to objectify the severity of symptoms in patients with idiopathic Parkinson's disease (iPD), but also to determine the therapeutic benefit of interventions. In particular, parameters of Deep Brain stimulation (DBS) with its short latency could be accurately assessed using sensor data. This study aimed at gaining insight into gait changes due to different DBS parameters in patients with subthalamic nucleus (STN) DBS. METHODS An analysis of various gait examinations was performed on 23 of the initially enrolled 27 iPD patients with chronic STN DBS. Stimulation settings were previously adjusted for either amplitude, frequency, or pulse width in a randomised order. A linear mixed effects model was used to analyse changes in gait speed, stride length, and maximum sensor lift. RESULTS The findings of our study indicate significant improvements in gait speed, stride length, and leg lift measurable with mobile gait sensors under different DBS parameter variations. Notably, we observed positive results at 85 Hz, which proved to be more effective than often applied higher frequencies and that these improvements were traceable across almost all conditions. While pulse widths did produce some improvements in leg lift, they were less well tolerated and had inconsistent effects on some of the gait parameters. Our research suggests that using lower frequencies of DBS may offer a more tolerable and effective approach to enhancing gait in individuals with iPD. CONCLUSIONS Our results advocate for lower stimulation frequencies for patients who report gait difficulties, especially those who can adapt their DBS settings remotely. They also show that mobile gait sensors could be incorporated into clinical practice in the near future.
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Affiliation(s)
- F Mügge
- Department of Neurology, University Hospital of Marburg, Baldingerstraße, Marburg, Germany
| | - U Kleinholdermann
- Department of Neurology, University Hospital of Marburg, Baldingerstraße, Marburg, Germany.
| | - A Heun
- Department of Neurology, University Hospital of Marburg, Baldingerstraße, Marburg, Germany
| | - M Ollenschläger
- Portabiles HealthCare Technologies, Henkestraße 91, 91052, Erlangen, Germany
| | - J Hannink
- Portabiles HealthCare Technologies, Henkestraße 91, 91052, Erlangen, Germany
| | - D J Pedrosa
- Department of Neurology, University Hospital of Marburg, Baldingerstraße, Marburg, Germany
- Center of Mind, Brain and Behaviour, Philipps University Marburg, Hans-Meerwein- Straße, Marburg, Germany
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Bäcklund T, Grip H, Öhberg F, Sundström N. Single sensor measurement of heel-height during the push-off phase of gait. Physiol Meas 2021; 42. [PMID: 34678800 DOI: 10.1088/1361-6579/ac325c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 10/22/2021] [Indexed: 11/11/2022]
Abstract
Objective. In healthy gait a forceful push-off is needed to get an efficient leg swing and propulsion, and a high heel lift makes a forceful push-off possible. The power of the push-off is decreased with increased age and in persons with impaired balance and gait. The aim of this study was to evaluate whether a wearable equipment (Striton) and algorithms to estimate vertical heel-height during gait from a single optical distance sensor is reliable and feasible for clinical applications.Approach. To assess heel-height with the Striton system an optical distance sensor was used to measure the distance to the floor along the shank. An algorithm was created to transform this measure to a vertical distance. The heel-height was validated in an experimental setup, against a 3D motion capture system (MCS), and test-retest and day-to-day tests were performed on 10 elderly persons. As a reference material 83 elderly persons were included, and heel-height was measured before and after surgery in four patients with the neurological disorder idiopathic normal pressure hydrocephalus (iNPH).Main results. In the experimental setup the accuracy was high with a maximum error of 2% at all distances, target colours and inclination angles, and the correlation to the MCS wasR= 0.94. Test-retest and day-to-day tests were equal within ±1.2 cm. Mean heel-height of the elderly persons was 16.5 ± 0.6 cm and in the patients with iNPH heel-height was increased from 11.2 cm at baseline to 15.3 cm after surgery.Significance. Striton can reliably measure heel-height during gait, with low test-retest and day-to-day variability. The system was easy to attach, and simple to use, which makes it suitable for clinical applications.
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Affiliation(s)
- Tomas Bäcklund
- Department of Radiation Sciences, Radiation Physics, Biomebdical Engineering, Umeå University, Umeå, Sweden
| | - Helena Grip
- Department of Radiation Sciences, Radiation Physics, Biomebdical Engineering, Umeå University, Umeå, Sweden
| | - Fredrik Öhberg
- Department of Radiation Sciences, Radiation Physics, Biomebdical Engineering, Umeå University, Umeå, Sweden
| | - Nina Sundström
- Department of Radiation Sciences, Radiation Physics, Biomebdical Engineering, Umeå University, Umeå, Sweden
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A Deep Learning Approach for Foot Trajectory Estimation in Gait Analysis Using Inertial Sensors. SENSORS 2021; 21:s21227517. [PMID: 34833590 PMCID: PMC8624119 DOI: 10.3390/s21227517] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 11/05/2021] [Accepted: 11/10/2021] [Indexed: 01/22/2023]
Abstract
Gait performance is an important marker of motor and cognitive decline in older adults. An instrumented gait analysis resorting to inertial sensors allows the complete evaluation of spatiotemporal gait parameters, offering an alternative to laboratory-based assessments. To estimate gait parameters, foot trajectories are typically obtained by integrating acceleration two times. However, to deal with cumulative integration errors, additional error handling strategies are required. In this study, we propose an alternative approach based on a deep recurrent neural network to estimate heel and toe trajectories. We propose a coordinate frame transformation for stride trajectories that eliminates the dependency from previous strides and external inputs. Predicted trajectories are used to estimate an extensive set of spatiotemporal gait parameters. We evaluate the results in a dataset comprising foot-worn inertial sensor data acquired from a group of young adults, using an optical motion capture system as a reference. Heel and toe trajectories are predicted with low errors, in line with reference trajectories. A good agreement is also achieved between the reference and estimated gait parameters, in particular when turning strides are excluded from the analysis. The performance of the method is shown to be robust to imperfect sensor-foot alignment conditions.
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10
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Orientation-Invariant Spatio-Temporal Gait Analysis Using Foot-Worn Inertial Sensors. SENSORS 2021; 21:s21113940. [PMID: 34200492 PMCID: PMC8201315 DOI: 10.3390/s21113940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Revised: 06/02/2021] [Accepted: 06/04/2021] [Indexed: 11/16/2022]
Abstract
Inertial sensors can potentially assist clinical decision making in gait-related disorders. Methods for objective spatio-temporal gait analysis usually assume the careful alignment of the sensors on the body, so that sensor data can be evaluated using the body coordinate system. Some studies infer sensor orientation by exploring the cyclic characteristics of walking. In addition to being unrealistic to assume that the sensor can be aligned perfectly with the body, the robustness of gait analysis with respect to differences in sensor orientation has not yet been investigated-potentially hindering use in clinical settings. To address this gap in the literature, we introduce an orientation-invariant gait analysis approach and propose a method to quantitatively assess robustness to changes in sensor orientation. We validate our results in a group of young adults, using an optical motion capture system as reference. Overall, good agreement between systems is achieved considering an extensive set of gait metrics. Gait speed is evaluated with a relative error of -3.1±9.2 cm/s, but precision improves when turning strides are excluded from the analysis, resulting in a relative error of -3.4±6.9 cm/s. We demonstrate the invariance of our approach by simulating rotations of the sensor on the foot.
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Real-time gait metric estimation for everyday gait training with wearable devices in people poststroke. ACTA ACUST UNITED AC 2021; 2. [PMID: 34396094 PMCID: PMC8360352 DOI: 10.1017/wtc.2020.11] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Hemiparetic walking after stroke is typically slow, asymmetric, and inefficient, significantly impacting activities of daily living. Extensive research shows that functional, intensive, and task-specific gait training is instrumental for effective gait rehabilitation, characteristics that our group aims to encourage with soft robotic exosuits. However, standard clinical assessments may lack the precision and frequency to detect subtle changes in intervention efficacy during both conventional and exosuit-assisted gait training, potentially impeding targeted therapy regimes. In this paper, we use exosuit-integrated inertial sensors to reconstruct three clinically meaningful gait metrics related to circumduction, foot clearance, and stride length. Our method corrects sensor drift using instantaneous information from both sides of the body. This approach makes our method robust to irregular walking conditions poststroke as well as usable in real-time applications, such as real-time movement monitoring, exosuit assistance control, and biofeedback. We validate our algorithm in eight people poststroke in comparison to lab-based optical motion capture. Mean errors were below 0.2 cm (9.9%) for circumduction, −0.6 cm (−3.5%) for foot clearance, and 3.8 cm (3.6%) for stride length. A single-participant case study shows our technique’s promise in daily-living environments by detecting exosuit-induced changes in gait while walking in a busy outdoor plaza.
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Estimation of stride-by-stride spatial gait parameters using inertial measurement unit attached to the shank with inverted pendulum model. Sci Rep 2021; 11:1391. [PMID: 33446858 PMCID: PMC7809129 DOI: 10.1038/s41598-021-81009-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 12/30/2020] [Indexed: 11/17/2022] Open
Abstract
Inertial measurement unit (IMU)-based gait analysis systems have become popular in clinical environments because of their low cost and quantitative measurement capability. When a shank is selected as the IMU mounting position, an inverted pendulum model (IPM) can accurately estimate its spatial gait parameters. However, the stride-by-stride estimation of gait parameters using one IMU on each shank and the IPMs has not been validated. This study validated a spatial gait parameter estimation method using a shank-based IMU system. Spatial parameters were estimated via the double integration of the linear acceleration transformed by the IMU orientation information. To reduce the integral drift error, an IPM, applied with a linear error model, was introduced at the mid-stance to estimate the update velocity. the gait data of 16 healthy participants that walked normally and slowly were used. The results were validated by comparison with those extracted from an optical motion-capture system; the results showed strong correlation (\documentclass[12pt]{minimal}
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\begin{document}$$r>0.9$$\end{document}r>0.9) and good agreement with the gait metrics (stride length, stride velocity, and shank vertical displacement). In addition, the biases of the stride length and stride velocity extracted using the motion capture system were smaller in the IPM than those in the previous method using the zero-velocity-update. The error variabilities of the gait metrics were smaller in the IPM than those in the previous method. These results indicated that the reconstructed shank trajectory achieved a greater accuracy and precision than that of previous methods. This was attributed to the IPM, which demonstrates that shank-based IMU systems with IPMs can accurately reflect many spatial gait parameters including stride velocity.
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Sharifi Renani M, Myers CA, Zandie R, Mahoor MH, Davidson BS, Clary CW. Deep Learning in Gait Parameter Prediction for OA and TKA Patients Wearing IMU Sensors. SENSORS (BASEL, SWITZERLAND) 2020; 20:E5553. [PMID: 32998329 PMCID: PMC7582246 DOI: 10.3390/s20195553] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 09/23/2020] [Accepted: 09/23/2020] [Indexed: 12/03/2022]
Abstract
Quantitative assessments of patient movement quality in osteoarthritis (OA), specifically spatiotemporal gait parameters (STGPs), can provide in-depth insight into gait patterns, activity types, and changes in mobility after total knee arthroplasty (TKA). A study was conducted to benchmark the ability of multiple deep neural network (DNN) architectures to predict 12 STGPs from inertial measurement unit (IMU) data and to identify an optimal sensor combination, which has yet to be studied for OA and TKA subjects. DNNs were trained using movement data from 29 subjects, walking at slow, normal, and fast paces and evaluated with cross-fold validation over the subjects. Optimal sensor locations were determined by comparing prediction accuracy with 15 IMU configurations (pelvis, thigh, shank, and feet). Percent error across the 12 STGPs ranged from 2.1% (stride time) to 73.7% (toe-out angle) and overall was more accurate in temporal parameters than spatial parameters. The most and least accurate sensor combinations were feet-thighs and singular pelvis, respectively. DNNs showed promising results in predicting STGPs for OA and TKA subjects based on signals from IMU sensors and overcomes the dependency on sensor locations that can hinder the design of patient monitoring systems for clinical application.
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Affiliation(s)
- Mohsen Sharifi Renani
- Center for Orthopaedic Biomechanics, University of Denver, Denver, CO 80208, USA; (C.A.M.); (R.Z.); (M.H.M.); (B.S.D.); (C.W.C.)
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Renggli D, Graf C, Tachatos N, Singh N, Meboldt M, Taylor WR, Stieglitz L, Schmid Daners M. Wearable Inertial Measurement Units for Assessing Gait in Real-World Environments. Front Physiol 2020; 11:90. [PMID: 32153420 PMCID: PMC7044412 DOI: 10.3389/fphys.2020.00090] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Accepted: 01/27/2020] [Indexed: 11/19/2022] Open
Abstract
Background Walking patterns can provide important indications of a person’s health status and be beneficial in the early diagnosis of individuals with a potential walking disorder. For appropriate gait analysis, it is critical that natural functional walking characteristics are captured, rather than those experienced in artificial or observed settings. To better understand the extent to which setting influences gait patterns, and particularly whether observation plays a varying role on subjects of different ages, the current study investigates to what extent people walk differently in lab versus real-world environments and whether age dependencies exist. Methods The walking patterns of 20 young and 20 elderly healthy subjects were recorded with five wearable inertial measurement units (ZurichMOVE sensors) attached to both ankles, both wrists and the chest. An automated detection process based on dynamic time warping was developed to efficiently identify the relevant sequences. From the ZurichMOVE recordings, 15 spatio-temporal gait parameters were extracted, analyzed and compared between motion patterns captured in a controlled lab environment (10 m walking test) and the non-controlled ecologically valid real-world environment (72 h recording) in both groups. Results Several parameters (Cluster A) showed significant differences between the two environments for both groups, including an increased outward foot rotation, step width, number of steps per 180° turn, stance to swing ratio, and cycle time deviation in the real-world. A number of parameters (Cluster B) showed only significant differences between the two environments for elderly subjects, including a decreased gait velocity (p = 0.0072), decreased cadence (p = 0.0051) and increased cycle time (p = 0.0051) in real-world settings. Importantly, the real-world environment increased the differences in several parameters between the young and elderly groups. Conclusion Elderly test subjects walked differently in controlled lab settings compared to their real-world environments, which indicates the need to better understand natural walking patterns under ecologically valid conditions before clinically relevant conclusions can be drawn on a subject’s functional status. Moreover, the greater inter-group differences in real-world environments seem promising regarding the sensitive identification of subjects with indications of a walking disorder.
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Affiliation(s)
- David Renggli
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Christina Graf
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Nikolaos Tachatos
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - Navrag Singh
- Institute for Biomechanics, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Mirko Meboldt
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
| | - William R Taylor
- Institute for Biomechanics, Department of Health Sciences and Technology, ETH Zurich, Zurich, Switzerland
| | - Lennart Stieglitz
- Department of Neurosurgery, University Hospital Zurich, Zurich, Switzerland
| | - Marianne Schmid Daners
- Product Development Group Zurich, Department of Mechanical and Process Engineering, ETH Zurich, Zurich, Switzerland
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15
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Indoor Trajectory Reconstruction of Walking, Jogging, and Running Activities Based on a Foot-Mounted Inertial Pedestrian Dead-Reckoning System. SENSORS 2020; 20:s20030651. [PMID: 31991597 PMCID: PMC7038347 DOI: 10.3390/s20030651] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 10/22/2019] [Accepted: 11/01/2019] [Indexed: 12/17/2022]
Abstract
The evaluation of trajectory reconstruction of the human body obtained by foot-mounted Inertial Pedestrian Dead-Reckoning (IPDR) methods has usually been carried out in controlled environments, with very few participants and limited to walking. In this study, a pipeline for trajectory reconstruction using a foot-mounted IPDR system is proposed and evaluated in two large datasets containing activities that involve walking, jogging, and running, as well as movements such as side and backward strides, sitting, and standing. First, stride segmentation is addressed using a multi-subsequence Dynamic Time Warping method. Then, detection of Toe-Off and Mid-Stance is performed by using two new algorithms. Finally, stride length and orientation estimation are performed using a Zero Velocity Update algorithm empowered by a complementary Kalman filter. As a result, the Toe-Off detection algorithm reached an F-score between 90% and 100% for activities that do not involve stopping, and between 71% and 78% otherwise. Resulting return position errors were in the range of 0.5% to 8.8% for non-stopping activities and 8.8% to 27.4% otherwise. The proposed pipeline is able to reconstruct indoor trajectories of people performing activities that involve walking, jogging, running, side and backward walking, sitting, and standing.
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16
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Martindale CF, Roth N, Gasner H, List J, Regensburger M, Eskofier BM, Kohl Z. Technical Validation of an Automated Mobile Gait Analysis System for Hereditary Spastic Paraplegia Patients. IEEE J Biomed Health Inform 2019; 24:1490-1499. [PMID: 31449035 DOI: 10.1109/jbhi.2019.2937574] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hereditary spastic paraplegias (HSP) represents a group of orphan neurodegenerative diseases with gait disturbance as the predominant clinical feature. Due to its rarity, research within this field is still limited. Aside from clinical analysis using established scales, gait analysis has been employed to enhance the understanding of the mechanisms behind the disease. However, state of the art gait analysis systems are often large, immobile and expensive. To overcome these limitations, this paper presents the first clinically relevant mobile gait analysis system for HSP patients. We propose an unsupervised model based on local cyclicity estimation and hierarchical hidden Markov models (LCE-hHMM). The system provides stride time, swing time, stance time, swing duration and cadence. These parameters are validated against a GAITRite system and manual sensor data labelling using a total of 24 patients within 2 separate studies. The proposed system achieves a stride time error of -0.00 ± 0.09 s (correlation coefficient, r = 1.00) and a swing duration error of -0.67 ± 3.27 % (correlation coefficient, r = 0.93) with respect to the GAITRite system. We show that these parameters are also correlated to the clinical spastic paraplegia rating scale (SPRS) in a similar manner to other state of the art gait analysis systems, as well as to supervised and general versions of the proposed model. Finally, we show a proof of concept for this system to be used to analyse alterations in the gait of individual patients. Thus, with further clinical studies, due to its automated approach and mobility, this system could be used to determine treatment effects in future clinical trials.
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17
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Kluge F, Hannink J, Pasluosta C, Klucken J, Gaßner H, Gelse K, Eskofier BM, Krinner S. Pre-operative sensor-based gait parameters predict functional outcome after total knee arthroplasty. Gait Posture 2018; 66:194-200. [PMID: 30199778 DOI: 10.1016/j.gaitpost.2018.08.026] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 08/20/2018] [Accepted: 08/22/2018] [Indexed: 02/02/2023]
Abstract
BACKGROUND Despite the general success of total knee arthroplasty (TKA) regarding patient-reported outcome measures, studies investigating gait function have shown diverse functional outcomes. Mobile sensor-based systems have recently been employed for accurate clinical gait assessments, as they allow a better integration of gait analysis into clinical routines as compared to laboratory based systems. RESEARCH QUESTION In this study, we sought to examine whether an accurate assessment of gait function of knee osteoarthritis patients with respect to surgery outcome evaluation after TKA using a mobile sensor-based gait analysis system is possible. METHODS A foot-worn sensor-based system was used to assess spatio-temporal gait parameters of 24 knee osteoarthritis patients one day before and one year after TKA, and in comparison to matched control participants. Patients were clustered into positive and negative responder groups using a heuristic approach regarding improvements in gait function. Machine learning was used to predict surgery outcome based on pre-operative gait parameters. RESULTS Gait function differed significantly between controls and patients. Patient-reported outcome measures improved significantly after surgery, but no significant global gait parameter difference was observed between pre- and post-operative status. However, the responder groups could be correctly predicted with an accuracy of up to 89% using pre-operative gait parameters. Patients exhibiting high pre-operative gait function were more likely to experience a functional decrease after surgery. Important gait parameters for the discrimination were stride time and stride length. SIGNIFICANCE The early identification of post-surgical functional outcomes of patients is of great importance to better inform patients pre-operatively regarding surgery success and to improve post-surgical management.
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Affiliation(s)
- Felix Kluge
- Machine Learning and Data Analytics Lab, Department of Computer Science, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Carl-Thiersch-Str. 2b, 91052 Erlangen, Germany.
| | - Julius Hannink
- Machine Learning and Data Analytics Lab, Department of Computer Science, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Carl-Thiersch-Str. 2b, 91052 Erlangen, Germany.
| | - Cristian Pasluosta
- Laboratory for Biomedical Microtechnology, Department of Microsystems Engineering, University of Freiburg, 79110 Freiburg, Germany.
| | - Jochen Klucken
- Molecular Neurology, University Hospital Erlangen, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - Heiko Gaßner
- Molecular Neurology, University Hospital Erlangen, Schwabachanlage 6, 91054 Erlangen, Germany.
| | - Kolja Gelse
- Department of Trauma Surgery, University Hospital Erlangen, Krankenhausstrasse 12, 91054 Erlangen, Germany.
| | - Bjoern M Eskofier
- Machine Learning and Data Analytics Lab, Department of Computer Science, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Carl-Thiersch-Str. 2b, 91052 Erlangen, Germany.
| | - Sebastian Krinner
- Department of Trauma Surgery, University Hospital Erlangen, Krankenhausstrasse 12, 91054 Erlangen, Germany.
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18
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Bertoli M, Cereatti A, Trojaniello D, Avanzino L, Pelosin E, Del Din S, Rochester L, Ginis P, Bekkers EMJ, Mirelman A, Hausdorff JM, Della Croce U. Estimation of spatio-temporal parameters of gait from magneto-inertial measurement units: multicenter validation among Parkinson, mildly cognitively impaired and healthy older adults. Biomed Eng Online 2018; 17:58. [PMID: 29739456 PMCID: PMC5941594 DOI: 10.1186/s12938-018-0488-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 04/23/2018] [Indexed: 11/11/2022] Open
Abstract
Background The use of miniaturized magneto-inertial measurement units (MIMUs) allows for an objective evaluation of gait and a quantitative assessment of clinical outcomes. Spatial and temporal parameters are generally recognized as key metrics for characterizing gait. Although several methods for their estimate have been proposed, a thorough error analysis across different pathologies, multiple clinical centers and on large sample size is still missing. The aim of this study was to apply a previously presented method for the estimate of spatio-temporal parameters, named Trusted Events and Acceleration Direct and Reverse Integration along the direction of Progression (TEADRIP), on a large cohort (236 patients) including Parkinson, mildly cognitively impaired and healthy older adults collected in four clinical centers. Data were collected during straight-line gait, at normal and fast walking speed, by attaching two MIMUs just above the ankles. The parameters stride, step, stance and swing durations, as well as stride length and gait velocity, were estimated for each gait cycle. The TEADRIP performance was validated against data from an instrumented mat. Results Limits of agreements computed between the TEADRIP estimates and the reference values from the instrumented mat were − 27 to 27 ms for Stride Time, − 68 to 44 ms for Stance Time, − 31 to 31 ms for Step Time and − 67 to 52 mm for Stride Length. For each clinical center, the mean absolute errors averaged across subjects for the estimation of temporal parameters ranged between 1 and 4%, being on average less than 3% (< 30 ms). Stride length mean absolute errors were on average 2% (≈ 25 mm). Error comparisons across centers did not show any significant difference. Significant error differences were found exclusively for stride and step durations between healthy elderly and Parkinsonian subjects, and for the stride length between walking speeds. Conclusions The TEADRIP method was effectively validated on a large number of healthy and pathological subjects recorded in four different clinical centers. Results showed that the spatio-temporal parameters estimation errors were consistent with those previously found on smaller population samples in a single center. The combination of robustness and range of applicability suggests the use of the TEADRIP as a suitable MIMU-based method for gait spatio-temporal parameter estimate in the routine clinical use. The present paper was awarded the “SIAMOC Best Methodological Paper 2017”.
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Affiliation(s)
- Matilde Bertoli
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy.,Interuniversity Centre of Bioengineering of the Human Neuromusculoskeletal System, Sassari, Italy
| | - Andrea Cereatti
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy.,Interuniversity Centre of Bioengineering of the Human Neuromusculoskeletal System, Sassari, Italy.,Department of Electronics and Telecommunications, Politecnico di Torino, Turin, Italy
| | | | - Laura Avanzino
- Department of Experimental Medicine, Section of Human Physiology and Centro Polifunzionale di Scienze Motorie, University of Genoa, Genoa, Italy
| | - Elisa Pelosin
- Department of Neuroscience, Rehabilitation, Ophthalmology, Genetics and Maternal Child Health, University of Genoa, Genoa, Italy
| | - Silvia Del Din
- Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Campus for Ageing and Vitality, Newcastle University, Newcastle, UK
| | - Lynn Rochester
- Institute of Neuroscience/Newcastle University Institute for Ageing, Clinical Ageing Research Unit, Campus for Ageing and Vitality, Newcastle University, Newcastle, UK.,Newcastle Upon Tyne Hospitals NHS Foundation Trust, Newcastle, UK
| | - Pieter Ginis
- Department of Rehabilitation Sciences, Neuromotor Rehabilitation Research Group, KU Leuven, Louvain, Belgium
| | - Esther M J Bekkers
- Department of Rehabilitation Sciences, Neuromotor Rehabilitation Research Group, KU Leuven, Louvain, Belgium.,Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Parkinson Centre Nijmegen, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Anat Mirelman
- Center for the Study of Movement, Cognition and Mobility, Neurological Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sagol School of Neuroscience and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Jeffrey M Hausdorff
- Center for the Study of Movement, Cognition and Mobility, Neurological Institute, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel.,Sagol School of Neuroscience and Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.,Rush Alzheimer's Disease Center and Department of Orthopaedic Surgery, Rush University Medical Center, Tel Aviv, Israel
| | - Ugo Della Croce
- Department of Biomedical Sciences, University of Sassari, Sassari, Italy. .,Interuniversity Centre of Bioengineering of the Human Neuromusculoskeletal System, Sassari, Italy.
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