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Bolt R, Heuvelmans P, Benjaminse A, Robinson MA, Gokeler A. An ecological dynamics approach to ACL injury risk research: a current opinion. Sports Biomech 2024; 23:1592-1605. [PMID: 34375159 DOI: 10.1080/14763141.2021.1960419] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 07/21/2021] [Indexed: 01/13/2023]
Abstract
Research of non-contact anterior cruciate ligament (ACL) injury risk aims to identify modifiable risk factors that are linked to the mechanisms of injury. Information from these studies is then used in the development of injury prevention programmes. However, ACL injury risk research often leans towards methods with three limitations: 1) a poor preservation of the athlete-environment relationship that limits the generalisability of results, 2) the use of a strictly biomechanical approach to injury causation that is incomplete for the description of injury mechanisms, 3) and a reductionist analysis that neglects profound information regarding human movement. This current opinion proposes three principles from an ecological dynamics perspective that address these limitations. First, it is argued that, to improve the generalisability of findings, research requires a well-preserved athlete-environment relationship. Second, the merit of including behaviour and the playing situation in the model of injury causation is presented. Third, this paper advocates that research benefits from conducting non-reductionist analysis (i.e., more holistic) that provides profound information regarding human movement. Together, these principles facilitate an ecological dynamics approach to injury risk research that helps to expand our understanding of injury mechanisms and thus contributes to the development of preventative measures.
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Affiliation(s)
- Ruben Bolt
- Department of Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Pieter Heuvelmans
- Department of Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
| | - Anne Benjaminse
- Department of Human Movement Sciences, University of Groningen, University Medical Center Groningen, Groningen, The Netherlands
- School of Sport Studies, Hanze University Groningen, Groningen, The Netherlands
| | - Mark A Robinson
- Research Institute for Sport and Exercise Sciences, Faculty of Science, Liverpool John Moores University, Liverpool, UK
| | - Alli Gokeler
- Exercise Science and Neuroscience Unit, Department Exercise & Health, Paderborn University, Paderborn, Germany
- Amsterdam Collaboration for Health and Safety in Sports, Department of Public and Occupational Health, Amsterdam Movement Sciences, VU University Medical Center, Amsterdam, The Netherlands
- Department of Sports Medicine, OCON Centre of Orthopaedic Surgery and Sports Medicine, Hengelo, The Netherlands
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de Freitas PB, Freitas SMSF, Dias MS. Synergic control of the minimum toe clearance in young and older adults during foot swing on treadmill walking in different speeds. Gait Posture 2024; 111:150-155. [PMID: 38703443 DOI: 10.1016/j.gaitpost.2024.04.025] [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: 05/31/2023] [Revised: 04/22/2024] [Accepted: 04/24/2024] [Indexed: 05/06/2024]
Abstract
BACKGROUND The vertical toe position at minimum toe clearance (MTC) in the swing phase is critical for walking safety. Consequently, the joints involved should be strictly controlled and coordinated to stabilize the foot at MTC. The uncontrolled manifold (UCM) hypothesis framework has been used to determine the existence of synergies that stabilize relevant performance variables during walking. However, no study investigated the presence of a multi-joint synergy stabilizing the foot position at MTC and the effects of age and walking speed on this synergy. RESEARCH QUESTIONS Is there a multi-joint synergy stabilizing MTC during treadmill walking? Does it depend on the persons' age and walking speed? METHODS Kinematic data from 23 young and 15 older adults were analyzed using the UCM approach. The participants walked on a treadmill at three speeds: slow, self-selected, and fast. The sagittal and frontal joint angles from the swing and stance legs and pelvis obliquity were used as motor elements and the vertical toe position at MTC was the performance variable. The variances in the joint space that affected (VORT, 'bad' variance) and did not affect (VUCM, 'good' variance) the toe position at MTC and the synergy index (ΔV) were computed. RESULTS The ΔV>0 was revealed for all subjects. Walking speed did not affect ΔV in older adults, whereas ΔV reduced with speed in young adults. ΔV was higher for older than for young adults at self-selected and fast speeds, owing to a lower VORT in the older group. SIGNIFICANCE The vertical toe position at MTC was stabilized by a strong multi-joint synergy. In older adults, this synergy was stronger, as they were better at limiting VORT than young adults. Reduced VORT in older adults could be caused by more constrained walking, which may be associated with anxiety due to walking on a treadmill.
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Affiliation(s)
- Paulo B de Freitas
- Interdisciplinary Graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo, Rua Galvão Bueno, 868, Liberdade, São Paulo, SP 01506-000, Brazil.
| | - Sandra M S F Freitas
- Graduate Program in Physical Therapy. Universidade Cidade de São Paulo, São Paulo, Rua Cesário Galeno, 475, Tatuapé, São Paulo, SP 03071-000, Brazil.
| | - Mateus S Dias
- Interdisciplinary Graduate Program in Health Sciences, Universidade Cruzeiro do Sul, São Paulo, Rua Galvão Bueno, 868, Liberdade, São Paulo, SP 01506-000, Brazil.
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Barsante LD, Arantes PMM, Vaz DV, Magalhães FA, Carvalho DS, Cruz AC, Resende RA, Ocarino JM, Fonseca ST, Souza TR. The Midfoot Joint Complex (Foot Arch) Contributes to the Upper Body Position in Bipedal Walking and Coordinates With the Lower Limb Joints. J Appl Biomech 2024; 40:241-249. [PMID: 38604601 DOI: 10.1123/jab.2023-0072] [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: 03/20/2023] [Revised: 12/04/2023] [Accepted: 02/27/2024] [Indexed: 04/13/2024]
Abstract
This study estimated the contribution of the midfoot joint complex (MJC) kinematics to the pelvis anterior-posterior positions during the stance phase of walking and investigated whether the MJC is functionally coordinated with the lower limb joints to maintain similar pelvic positions across steps. Hip, knee, ankle, and MJC sagittal angles were measured in 11 nondisabled participants during walking. The joints' contributions to pelvic positions were computed through equations derived from a link-segment model. Functional coordination across steps was identified when the MJC contribution to pelvic position varied and the summed contributions of other joints varied in the opposite direction (strong negative covariations [r ≤ -.7] in stance phase instants). We observed that the MJC plantarflexion (arch raising) during the midstance and late stance leads the pelvis backward, avoiding excessive forward displacement. The MJC was the second joint that contributed most to the pelvis positions (around 18% of all joints' contributions), after the ankle joint. The MJC and ankle were the joints that were most frequently coordinated with the other joints (≅70% of the stance phase duration). The findings suggest that the MJC is part of the kinematic chain that determines pelvis positions during walking and is functionally coordinated with the lower limb joints.
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Affiliation(s)
- Leonardo D Barsante
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Paula M M Arantes
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Daniela V Vaz
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Fabricio A Magalhães
- College of Education, Health, and Human Sciences, Department of Biomechanics, University of Nebraska, Omaha, USA
| | - Diego S Carvalho
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Aline C Cruz
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Renan A Resende
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Juliana M Ocarino
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Sérgio T Fonseca
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Thales R Souza
- Graduate Program in Rehabilitation Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
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Piscitelli D, Buttram A, Abernathy K, Canelón J, Knighten D, Solnik S. Clinically relevant estimation of minimal number of trials for the uncontrolled manifold analysis. J Biomech 2024; 171:112195. [PMID: 38878344 DOI: 10.1016/j.jbiomech.2024.112195] [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: 05/17/2024] [Revised: 06/03/2024] [Accepted: 06/10/2024] [Indexed: 07/06/2024]
Abstract
Movement biomarkers are crucial for assessing sensorimotor impairments and tracking the effects of interventions over time. The Uncontrolled Manifold (UCM) analysis has been proposed as a novel biomarker for evaluating movement stability and coordination in various motor tasks across neurological and musculoskeletal disorders. Through inter-trial analysis, the UCM partitions the variance of elemental variables (e.g., finger forces) into components that affect (VORT) and do not affect (VUCM) a performance variable (e.g., total force). A third index, ΔV, is computed as the normalized difference between VORT and VUCM. However, the minimum number of trials required to achieve stable UCM estimates, considering its clinimetric properties, is unknown. This study aimed to determine the minimal number (N) of trials for UCM estimates by computing bootstrap estimates of standard errors (SE) at different N trials using thresholds based on the minimal detectable change (MDC, i.e., the minimum change in an outcome measure beyond measurement error). Thirteen adults (24.6 ± 1.1 years old) performed a finger-pressing coordination task. We computed the 95 % confidence intervals (CI) of bootstrap SE distributions for each UCM estimate and detected the lowest number of trials with the 95 % CI of SE below each MDC threshold. We found the minimal N of trials required was VUCM = 14, VORT = 4 and ΔV = 18. Our findings highlight that a relatively low number of trials (i.e., N = 18) are sufficient to compute all UCM estimates beyond the MDC, supporting the use of the UCM framework in clinical settings where many repetitions of a motor task are not practical.
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Affiliation(s)
| | - Adrien Buttram
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Karlie Abernathy
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - José Canelón
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Damon Knighten
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Stanislaw Solnik
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA.
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Garofolini A, Mickle KJ, McLaughlin P, Taylor SB. Assessing the effects of foot strike patterns and shoe types on the control of leg length and orientation in running. Sci Rep 2024; 14:2220. [PMID: 38278965 PMCID: PMC10817954 DOI: 10.1038/s41598-024-52446-0] [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: 11/15/2023] [Accepted: 01/18/2024] [Indexed: 01/28/2024] Open
Abstract
This research investigates the stabilization of leg length and orientation during the landing phase of running, examining the effects of different footwear and foot strike patterns. Analyzing kinematic data from twenty male long-distance runners, both rearfoot and forefoot strikers, we utilized the Uncontrolled Manifold approach to assess stability. Findings reveal that both leg length and orientation are indeed stabilized during landing, challenging the hypothesis that rearfoot strikers exhibit less variance in deviations than forefoot strikers, and that increased footwear assistance would reduce these deviations. Surprisingly, footwear with a lower minimalist index enhanced post-landing stability, suggesting that cushioning contributes to both force dissipation and leg length stability. The study indicates that both foot strike patterns are capable of effectively reducing task-relevant variance, with no inherent restriction on flexibility for rearfoot strikers. However, there is an indication of potential reliance on footwear for stability. These insights advance our understanding of the biomechanics of running, highlighting the role of footwear in stabilizing leg length and orientation, which has significant implications for running efficiency and injury prevention.
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Affiliation(s)
| | - Karen J Mickle
- School of Environmental and Life Sciences, University of Newcastle, Ourimbah, NSW, Australia
| | - Patrick McLaughlin
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia
| | - Simon B Taylor
- Institute for Health and Sport (IHES), Victoria University, Melbourne, Australia
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Piscitelli D, Buttram A, Gibson S, Hager J, Thomas B, Solnik S. Test-Retest reliability and measurement error of the uncontrolled manifold analysis: A step towards the clinical translation. J Biomech 2024; 162:111902. [PMID: 38103314 DOI: 10.1016/j.jbiomech.2023.111902] [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: 08/29/2023] [Revised: 12/04/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
The uncontrolled manifold (UCM) analysis has gained broad application in biomechanics and neuroscience for investigating the structure of motor variability in functional tasks. The UCM utilizes inter-trial analysis to partition the variance of elemental variables (e.g., finger forces, joint angles) that affect (VORT) and do not affect (VUCM) a performance variable (e.g., total force, end-effector position). However, to facilitate the translation of UCM into clinical settings, it is crucial to demonstrate the reliability of UCM estimates: VORT, VUCM, and their normalized difference, ΔV. This study aimed to determine the test-retest reliability using the intraclass correlation coefficient (ICC3,K), Bland-Altman plots, the standard error of measurement (SEM), and the minimal detectable change (MDC) of UCM estimate. Fifteen healthy individuals (24.8 ± 1.2 yrs old) performed a finger coordination task, with sessions separated by one hour, one day, and one week. Excellent reliability was found for VORT (ICC3,K = 0.97) and VUCM (ICC3,K = 0.92), whereas good reliability was observed for ΔV (ICC3,K = 0.84). Bland-Altman plots reveled no systematic differences. SEM% values were 24.57 %, 26.80 % and 12.49 % for VORT, VUCM and ΔV respectively, while the normalized MDC% values were 68.12 %, 74.30 % and 34.61 % for VORT, VUCM and ΔV respectively. Our results support the use of UCM as a reliable method for investigating the structure of movement variability. The excellent measurement properties make the UCM a promising tool for tracking changes in motor behavior over time (i.e., effects of interventions in prospective studies).
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Affiliation(s)
| | - Adrien Buttram
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Stephanie Gibson
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Joel Hager
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Ben Thomas
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA
| | - Stanislaw Solnik
- Department of Physical Therapy, University of North Georgia, Dahlonega, GA, USA.
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Wargel A, van Andel S, Federolf P. Do Bernstein's Stages of Learning Apply after Stroke? A Scoping Review on the Development of Whole-Body Coordination after Cerebrovascular Accidents. Brain Sci 2023; 13:1713. [PMID: 38137161 PMCID: PMC10741574 DOI: 10.3390/brainsci13121713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Revised: 12/01/2023] [Accepted: 12/11/2023] [Indexed: 12/24/2023] Open
Abstract
Stroke is one of the leading causes of disability around the world, presenting unique challenges in motor development during the rehabilitation process. Based on studies in movement and sports science, thorough knowledge has accumulated on the development of movement skills. Through the works of Nikolai Bernstein, it has been established that when learning new skills, people tend to first simplify coordination by 'freezing' their degrees of freedom, after which they start building efficiency by 'releasing' specific degrees of freedom. If a similar pattern of development can be established post-stroke, it would imply that lessons learned in sports skill acquisition can also be implemented to optimize stroke rehabilitation. The current scoping review aims to assess whether the Bernsteinian freezing-to-releasing stages of learning also apply to developing whole-body movement skills after stroke. To this end, we systematically screened the existing literature for studies involving a longitudinal measure of whole-body coordination after a stroke. Only five articles met the criteria for inclusion, indicating a gap in research on this topic. Based on the observations within these articles, we could neither confirm nor reject whether the freezing-to-releasing process can apply after a stroke. We could, however, hypothesize a detailed description of the freezing-to-releasing process, which can be assessed in future works.
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Affiliation(s)
- Anna Wargel
- Department of Sport Science, University of Innsbruck, 6020 Innsbruck, Austria; (A.W.)
| | - Steven van Andel
- Department of Sport Science, University of Innsbruck, 6020 Innsbruck, Austria; (A.W.)
- IJsselheem Foundation, 8266 AB Kampen, The Netherlands
| | - Peter Federolf
- Department of Sport Science, University of Innsbruck, 6020 Innsbruck, Austria; (A.W.)
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Pan Z, Liu L, Li X, Ma Y. A long short-term memory modeling-based compensation method for muscle synergy. Med Eng Phys 2023; 120:104054. [PMID: 37838409 DOI: 10.1016/j.medengphy.2023.104054] [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: 03/15/2023] [Revised: 07/29/2023] [Accepted: 09/11/2023] [Indexed: 10/16/2023]
Abstract
Muscle synergy containing temporal and spatial patterns of muscle activity has been frequently used in prediction of kinematic characteristics. However, there is often some discrepancy between the predicted results based on muscle synergy and the actual movement performance. This study aims to propose a new method for compensating muscle synergy that allows the compensated synergy signal to predict kinematic characteristics more accurately. The study used the change of direction in running as background. Non-negative matrix factorisation was used to extract the muscle synergy during the change of direction at different angles. A non-linear association between synergy and the height of pelvic mass centre was established using long and short-term memory neural networks. Based on this model, the height fluctuations of the pelvic centre of mass are used as input and predict the fluctuations of the synergy which were used to compensate for the original synergy in different ways. The accuracy of the synergies compensated in different ways in predicting pelvic centre of mass movement was then assessed by back propagation neural networks. It was found that the compensated synergy significantly improves accuracy in predicting pelvic centre of mass displacement (R2, p < 0.05). The predicted results of all-compensation are significantly different from actual performance in the end-swing (p < 0.05). The predicted results of half-compensation do not differ significantly from the actual performance, and its damage to the original synergy is smaller and does not increase with angle compared to all-compensation. The all-compensation may be affected by individual variability and lead to increased errors. The half-compensation can improve the predictive accuracy of the synergy while reducing the adjustment to the original synergy.
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Affiliation(s)
- Zhengye Pan
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Lushuai Liu
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Xingman Li
- College of Physical Education and Sports, Beijing Normal University, Beijing, China
| | - Yunchao Ma
- College of Physical Education and Sports, Beijing Normal University, Beijing, China.
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9
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Koh K, Oppizzi G, Kehs G, Zhang LQ. Abnormal coordination of upper extremity during target reaching in persons post stroke. Sci Rep 2023; 13:12838. [PMID: 37553412 PMCID: PMC10409717 DOI: 10.1038/s41598-023-39684-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 07/28/2023] [Indexed: 08/10/2023] Open
Abstract
Understanding abnormal synergy of the upper extremity (UE) in stroke survivors is critical for better identification of motor impairment. Here, we investigated to what extent stroke survivors retain the ability to coordinate multiple joints of the arm during a reaching task. Using an exoskeleton robot, 37 stroke survivors' arm joint angles (θ) and torques (τ) during hand reaching in the horizontal plane was compared to that of 13 healthy controls. Kinematic and kinetic coordination patterns were quantified as variances of the multiple-joint angles and multiple-joint torques across trials, respectively, that were partitioned into task-irrelevant variance (TIVθ and TIVτ) and task-relevant variance (TRVθ and TRVτ). TIVθ and TRVθ (or TIVτ and TRVτ) led to consistent and inconsistent hand position (or force), respectively. The index of synergy (ISθ and ISτ) was determined as [Formula: see text] and [Formula: see text] for kinematic and kinetic coordination patterns, respectively. Both kinematic ISθ and kinetic ISτ in the stroke group were significantly lower than that of the control group, indicating stroke survivors had impaired reaching abilities in utilizing the multiple joints of the UE for successful completion of a reaching task. The reduction of kinematic ISθ in the stroke group was mainly attributed to the lower TIVθ as compared to the control group, while the reduction of kinetic ISτ was mainly due to the higher [Formula: see text] as well as lower TIVτ. Our results also indicated that stroke may lead to motor deficits in formation of abnormal kinetic synergistic movement of UE, especially during outward movement. The findings in abnormal synergy patterns provides a better understanding of motor impairment, suggesting that impairment-specific treatment could be identified to help improve UE synergies, focusing on outward movements.
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Affiliation(s)
- Kyung Koh
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, 20742, USA
| | - Giovanni Oppizzi
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, 20742, USA
- Department of Physical Therapy and Rehabilitation Science, University of Maryland, 100 Penn St, Baltimore, MD, 21201, USA
| | - Glenn Kehs
- University of Maryland Rehabilitation and Orthopaedic Institute, Baltimore, MD, 21207, USA
- Department of Neurology, University of Maryland, Baltimore, MD, 21201, USA
| | - Li-Qun Zhang
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, 20742, USA.
- Department of Physical Therapy and Rehabilitation Science, University of Maryland, 100 Penn St, Baltimore, MD, 21201, USA.
- Department of Orthopaedics, University of Maryland, Baltimore, MD, 21201, USA.
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Shoja O, Shojaei M, Hassanlouei H, Towhidkhah F, Amiri M, Boroomand H, Rahimi N, Zhang L. Lack of visual information alters lower limb motor coordination to control center of mass trajectory during walking. J Biomech 2023; 155:111650. [PMID: 37245385 DOI: 10.1016/j.jbiomech.2023.111650] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 05/09/2023] [Accepted: 05/19/2023] [Indexed: 05/30/2023]
Abstract
Vision, as queen of the senses, plays a critical role in guiding locomotion. Little is known about the effects of vision on gait coordination in terms of variability. The uncontrolled manifold (UCM) approach offers a window to the structure of motor variability that has been difficult to obtain from the traditional correlation analysis. In this study, we used the UCM analysis to quantify how the lower limb motion is coordinated to control the center of mass (COM) while walking under different visual conditions. We also probed how synergy strength evolved along the stance phase. Ten healthy participants walked on the treadmill with and without visual information. Leg joint angle variance with respect to the whole-body COM was partitioned into good (i.e., the one that kept the COM) and bad (i.e., the one that changed the COM) variances. We observed that after vision was eliminated, both variances increased throughout the stance phase while the strength of the synergy (the normalized difference between the two variances) decreased significantly and even reduced to zero at heel contact. Thus, walking with restricted vision alters the strength of the kinematic synergy to control COM in the plane of progression. We also found that the strength of this synergy varied across different walking phases and gait events in both visual conditions. We concluded that the UCM analysis can quantify altered coordination of COM when vision is blocked and sheds insights on the role of vision in the synergistic control of locomotion.
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Affiliation(s)
- Otella Shoja
- Department of Motor Behavior, Faculty of Sport Sciences, Alzahra University, Tehran, Iran; Department of Neuroscience, University of Montreal, Montreal, QC, Canada.
| | - Masoumeh Shojaei
- Department of Motor Behavior, Faculty of Sport Sciences, Alzahra University, Tehran, Iran
| | - Hamidollah Hassanlouei
- Department of Motor Behavior, Faculty of Sport Sciences and Health, Shahid Beheshti University, Tehran, Iran
| | - Farzad Towhidkhah
- Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Mohsen Amiri
- Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Hesam Boroomand
- Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Negar Rahimi
- Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | - Lei Zhang
- Institute for Neural Computation, Ruhr University Bochum, Germany
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11
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Devetak GF, Bohrer RCD, Rinaldin C, Rodacki ALF, Manffra EF. Time profile of kinematic synergies of stroke gait. Clin Biomech (Bristol, Avon) 2023; 106:105990. [PMID: 37209470 DOI: 10.1016/j.clinbiomech.2023.105990] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 05/03/2023] [Accepted: 05/10/2023] [Indexed: 05/22/2023]
Abstract
BACKGROUND In stroke subjects, the motor skills differ between sides and among subjects with different levels of motor recovery, impacting inter-joint coordination. How these factors can affect the kinematic synergies over time during gait has not been investigated yet. This work aimed to determine the time profile of kinematic synergies of stroke patients throughout the single support phase of gait. METHODS Kinematic data from 17 stroke and 11 healthy individuals was recorded using a Vicon System. The Uncontrolled Manifold approach was employed to determine the distribution of components of variability and the synergy index. To analyze the time profile of kinematic synergies, we applied the statistical parametric mapping method. Comparisons were made within the stroke group (paretic and non-paretic limbs) and between groups (stroke and healthy). The stroke group was also subdivided into subgroups with worse and better motor recovery. FINDINGS There are significant differences in synergy index at the end of the single support phase between stroke and healthy subjects; paretic and non-paretic limbs; and paretic limb according to the motor recovery. Comparisons of mean values showed significantly larger values of synergy index for the paretic limb compared to the non-paretic and healthy. INTERPRETATION Despite the sensory-motor deficits and the atypical kinematic behavior, stroke patients can produce joint covariations to control the center of mass trajectory in the forward progression plane, but the modulation of the synergy is impaired, reflecting altered adjustments, especially in the paretic limb of subjects with worse levels of motor recovery.
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Affiliation(s)
- Gisele Francini Devetak
- Clinics Hospital, Federal University of Paraná (UFPR/EBSERH), Brazil; Graduate Program on Health Technology, Pontifícia Universidade Católica do Paraná (PUCPR), Brazil.
| | | | - Carla Rinaldin
- Graduate Program on Health Technology, Pontifícia Universidade Católica do Paraná (PUCPR), Brazil
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Tomita Y, Iizuka T, Turpin NA. Effects of postural instability on the coordination between posture and arm reaching. Hum Mov Sci 2023; 89:103088. [PMID: 37054492 DOI: 10.1016/j.humov.2023.103088] [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: 05/10/2022] [Revised: 04/03/2023] [Accepted: 04/04/2023] [Indexed: 04/15/2023]
Abstract
Reaching from standing requires adjustments of hand movement and posture, which are assured by redundant kinematic degrees of freedom. However, the increased demand for postural adjustments may interfere with the stability of reaching. The objective of this study was to investigate the effect of postural instability on the use of kinematic redundancy to stabilize the finger and center-of-mass trajectories during reaching from standing in healthy adults. Sixteen healthy young adults performed reaching movements from standing with and without postural instability induced by small base-of-support. The three-dimensional positions of 48 markers were recorded at 100 Hz. The uncontrolled manifold (UCM) analysis was performed separately with the finger and center-of-mass positions being the performance variables, and joint angles being the elemental variables. ΔV, the normalized difference between the variance in joint angle that does not affect task performance (VUCM) and the variance that does affect task performance (VORT), was calculated separately for finger (ΔVEP) and center-of-mass (ΔVCOM) positions, and was compared between stable and unstable base-of-support conditions. ΔVEP decreased after movement onset and reached its minimum value at around 30-50% of the normalized movement time, and increased until movement offset, while ΔVCOM remained stable. At 60%-100% normalized movement time, ΔVEP was significantly reduced in the unstable base-of-support, compared to the stable base-of-support condition. ΔVCOM remained similar between the two conditions. At movement offset, ΔVEP was significantly reduced in the unstable base-of-support, compared to the stable base-of-support condition, and was associated with a substantial increase in VORT. Postural instability might reduce the ability to use kinematic redundancy to stabilize the reaching movement. The central nervous system may prioritize the maintenance of postural stability over focal movement when postural stability is challenged.
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Affiliation(s)
- Yosuke Tomita
- Department of Physical Therapy, Graduate School of Health Care, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan.
| | - Tomoki Iizuka
- Department of Physical Therapy, Graduate School of Health Care, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan; Department of Rehabilitation, Kurosawa Hospital, Takasaki, Gunma, Japan
| | - Nicolas A Turpin
- IRISSE (EA 4075), Department of Sport Sciences (STAPS), University of la Réunion, Tampon, France
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Devetak GF, Rinaldin CDP, Ranciaro M, Neto GNN, Bohrer RCD, Manffra EF. Does the number of steps needed for UCM gait analysis differs between healthy and stroke? J Biomech 2022; 144:111353. [DOI: 10.1016/j.jbiomech.2022.111353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 09/12/2022] [Accepted: 10/17/2022] [Indexed: 11/27/2022]
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Toda H, Hashimoto Y, Ibara T, Tada M. Effect of vibrotactile stimulation of the hallux nail on segmental coordination: A secondary analysis using uncontrolled manifold analysis. J Biomech 2022; 141:111234. [PMID: 35907290 DOI: 10.1016/j.jbiomech.2022.111234] [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: 02/24/2022] [Revised: 07/16/2022] [Accepted: 07/21/2022] [Indexed: 10/16/2022]
Abstract
Controlling center of mass (CoM) movement in the mediolateral direction is imperative for stable walking. During walking, CoM movement is adjusted by the coordination of each body segment, which can be evaluated using uncontrolled manifold (UCM) analysis. UCM analysis evaluates segmental coordination by analyzing variablity in motor movement among the different segments of the body. The vibrotactile stimulation of the hallux nail can augment the sensory information of the plantar surface for necessary motor control. This study aims to investigate the effect of the vibrotactile stimulation of the hallux nail on segmental coordination to control CoM movement in the mediolateral direction during walking. Thirteen healthy men participated in the study. A vibrator was attached to each hallux nail, and pressure sensors were placed under the hallux balls. When the hallux ball was in contact with the floor, vibration stimulation was applied. A three-dimensional motion analysis system was used to measure the segment angles during walking, and UCM analysis was used to evaluate kinematic synergy for controlling CoM movement in the mediolateral direction. Subsequently, segment angles were used as an elemental variable. The synergy index and bad variability as motor noise were negatively related to the status without the stimulation. Vibrotactile stimulation in young people was more effective for people with large motor noise and a small synergy index during the single-stance phase. Thus, kinematic synergy can be immediately changed by sensory input using vibrotactile stimulation of the hallux nail, although applying vibration stimulation should be considered in advance.
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Affiliation(s)
- Haruki Toda
- Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Waterfront 3F, 2-3-26 Aomi, Koto-ku, Tokyo, Japan.
| | - Yuki Hashimoto
- Department of Intelligence Interaction Technology, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki, Japan; JST, PREST, 4-1-8 Honcho, Kawaguchi, Saitama, Japan
| | - Takuya Ibara
- Department of Functional Joint Anatomy, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo, Japan
| | - Mitsunori Tada
- Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Waterfront 3F, 2-3-26 Aomi, Koto-ku, Tokyo, Japan
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Yamagata M, Tateuchi H, Shimizu I, Ichihashi N. Changes in kinematic synergy in older adults during walking: A two-year follow-up study. Gait Posture 2022; 96:244-250. [PMID: 35700642 DOI: 10.1016/j.gaitpost.2022.05.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 05/19/2022] [Accepted: 05/24/2022] [Indexed: 02/02/2023]
Abstract
BACKGROUND A well-controlled center of mass (CoM) in a coordinated segmental manner is required during gait. A synergy index that quantifies the strength of the synergistic control of the body segments that control the CoM can be evaluated using uncontrolled manifold (UCM) analysis. Several studies have compared the synergy index between older and younger adults; however, contradictory results have been found regarding age-related changes in the synergy index. Moreover, no study has investigated these changes longitudinally. RESEARCH QUESTION To evaluate age-related changes in the synergy index to control the CoM during gait in a longitudinal study. METHODS Twenty-five older adults participated at a baseline visit. The gait task at the two-year follow-up was completed by 16 older adults. Participants walked on a 6-m walkway at baseline and the two-year follow-up, and kinematic data were collected. Using UCM analysis, the synergy indices controlling CoM in the mediolateral and vertical directions were evaluated at baseline and follow-up. We also evaluated the Timed Up and Go (TUG) test and the strength of the knee extensor at both periods. RESULTS We found that TUG was significantly slower at follow-up; however, no difference was found in muscle strength. The synergy index in the mediolateral direction increased significantly after two years; such increases were found in individuals with decreased gait speed. SIGNIFICANCE This study showed that changes in gait patterns, including decreasing gait speed and increasing segmental coordination, may be important for gait with appropriate postural control relative to the environment and dynamic stability of the body in individuals with low functional mobility.
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Affiliation(s)
- Momoko Yamagata
- Faculty of Rehabilitation, Kansai Medical University, 18-89 Uyama Higashimachi, Hirakata, Osaka 573-1136, Japan; Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
| | - Hiroshige Tateuchi
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
| | - Itsuroh Shimizu
- Fukui General Clinic, 1-42-1 Nittazuka, Fukui-shi,Fukui 910-0067, Japan
| | - Noriaki Ichihashi
- Human Health Sciences, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan
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Möhler F, Fadillioglu C, Scheffler L, Müller H, Stein T. Running-Induced Fatigue Changes the Structure of Motor Variability in Novice Runners. BIOLOGY 2022; 11:biology11060942. [PMID: 35741462 PMCID: PMC9220051 DOI: 10.3390/biology11060942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Revised: 06/15/2022] [Accepted: 06/18/2022] [Indexed: 11/16/2022]
Abstract
Understanding the effects of fatigue is a central issue in the context of endurance sports. Given the popularity of running, there are numerous novices among runners. Therefore, understanding the effects of fatigue in novice runners is an important issue. Various studies have drawn conclusions about the control of certain variables by analyzing motor variability. One variable that plays a crucial role during running is the center of mass (CoM), as it reflects the movement of the whole body in a simplified way. Therefore, the aim of this study was to analyze the effects of fatigue on the motor variability structure that stabilizes the CoM trajectory in novice runners. To do so, the uncontrolled manifold approach was applied to a 3D whole-body model using the CoM as the result variable. It was found that motor variability increased with fatigue (UCMꓕ). However, the UCMRatio did not change. This indicates that the control of the CoM decreased, whereas the stability was not affected. The decreases in control were correlated with the degree of exhaustion, as indicated by the Borg scale (during breaking and flight phase). It can be summarized that running-induced fatigue increases the step-to-step variability in novice runners and affects the control of their CoM.
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Affiliation(s)
- Felix Möhler
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany; (C.F.); (L.S.); (T.S.)
- Correspondence:
| | - Cagla Fadillioglu
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany; (C.F.); (L.S.); (T.S.)
| | - Lucia Scheffler
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany; (C.F.); (L.S.); (T.S.)
| | - Hermann Müller
- Training Science, Department of Sports Science, Justus-Liebig-Universität Giessen, 35394 Giessen, Germany;
| | - Thorsten Stein
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany; (C.F.); (L.S.); (T.S.)
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Shafizadegan Z, Sarrafzadeh J, Farahmand F, Salehi R, Rasouli O. Uncontrolled manifold analysis of gait kinematic synergy during normal and narrow path walking in individuals with knee osteoarthritis compared to asymptomatic individuals. J Biomech 2022; 141:111203. [PMID: 35751924 DOI: 10.1016/j.jbiomech.2022.111203] [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: 02/21/2022] [Revised: 06/13/2022] [Accepted: 06/16/2022] [Indexed: 11/25/2022]
Abstract
Knee osteoarthritis (KOA) is a common musculoskeletal disorder resulting in altered gait patterns. Uncontrolled manifold (UCM) analysis has been demonstrated as a useful approach for quantitative analysis of motor variability and synergies. The present study aimed to investigate the changes in the kinematic synergy, controlling the center of mass (COM) position while walking on normal and narrow paths in people with KOA compared to asymptomatic participants. In this cross-sectional study, twenty people with mild to moderate KOA and twenty asymptomatic individuals walked at their comfortable preferred speed across normal and narrow paths on a treadmill. The UCM analysis was performed separately using the lower limb segmental angles as elemental variables and the COM displacement as a performance variable during the stance phase of gait for the frontal and sagittal planes. The results revealed that KOA and asymptomatic individuals could exploit kinematic synergy to control the COM displacement regardless of walking conditions (p < 0.05). Furthermore, the variance within the UCM and synergy index were significantly higher on the narrow path than the normal walking in the mediolateral direction in the KOA group (p < 0.05). The findings of this study suggest that individuals with KOA modify their gait kinematic variability to ensure a stronger kinematic synergy when walking on a challenging narrow path.
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Affiliation(s)
- Zohreh Shafizadegan
- Rehabilitation Research Center, Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran; Musculoskeletal Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Javad Sarrafzadeh
- Rehabilitation Research Center, Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran
| | - Farzam Farahmand
- Department of Mechanical Engineering, Sharif University of Technology, Tehran, Iran
| | - Reza Salehi
- Rehabilitation Research Center, Department of Physiotherapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
| | - Omid Rasouli
- Department of Neuromedicine and Movement Science, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
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Fadillioglu C, Kanus L, Möhler F, Ringhof S, Hellmann D, Stein T. Influence of Controlled Stomatognathic Motor Activity on Sway, Control and Stability of the Center of Mass During Dynamic Steady-State Balance—An Uncontrolled Manifold Analysis. Front Hum Neurosci 2022; 16:868828. [PMID: 35399352 PMCID: PMC8989727 DOI: 10.3389/fnhum.2022.868828] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Accepted: 03/02/2022] [Indexed: 11/13/2022] Open
Abstract
Multiple sensory signals from visual, somatosensory and vestibular systems are used for human postural control. To maintain postural stability, the central nervous system keeps the center of mass (CoM) within the base of support. The influence of the stomatognathic motor system on postural control has been established under static conditions, but it has not yet been investigated during dynamic steady-state balance. The purpose of the study was to investigate the effects of controlled stomatognathic motor activity on the control and stability of the CoM during dynamic steady-state balance. A total of 48 physically active and healthy adults were assigned to three groups with different stomatognathic motor conditions: jaw clenching, tongue pressing and habitual stomatognathic behavior. Dynamic steady-state balance was assessed using an oscillating platform and the kinematic data were collected with a 3D motion capturing system. The path length (PL) of the 3D CoM trajectory was used for quantifying CoM sway. Temporal dynamics of the CoM movement was assessed with a detrended fluctuation analysis (DFA). An uncontrolled manifold (UCM) analysis was applied to assess the stability and control of the CoM with a subject-specific anthropometric 3D model. The statistical analysis revealed that the groups did not differ significantly in PL, DFA scaling exponents or UCM parameters. The results indicated that deliberate jaw clenching or tongue pressing did not seem to affect the sway, control or stability of the CoM on an oscillating platform significantly. Because of the task-specificity of balance, further research investigating the effects of stomatognathic motor activities on dynamic steady-state balance with different movement tasks are needed. Additionally, further analysis by use of muscle synergies or co-contractions may reveal effects on the level of muscles, which were not visible on the level of kinematics. This study can contribute to the understanding of postural control mechanisms, particularly in relation to stomatognathic motor activities and under dynamic conditions.
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Affiliation(s)
- Cagla Fadillioglu
- BioMotion Center, Institute of Sports and Sports Science, Karlsruhe Institute of Technology, Karlsruhe, Germany
- *Correspondence: Cagla Fadillioglu
| | - Lisa Kanus
- Department of Prosthodontics, University of Würzburg, Würzburg, Germany
| | - Felix Möhler
- BioMotion Center, Institute of Sports and Sports Science, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Steffen Ringhof
- Department of Sport and Sport Science, University of Freiburg, Freiburg, Germany
| | - Daniel Hellmann
- Department of Prosthodontics, University of Würzburg, Würzburg, Germany
- Dental Academy for Continuing Professional Development, Karlsruhe, Germany
| | - Thorsten Stein
- BioMotion Center, Institute of Sports and Sports Science, Karlsruhe Institute of Technology, Karlsruhe, Germany
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Sarrafzadeh J, Shafizadegan Z, Salehi R, Farahmand F, Rasouli O. The effects of challenging walking conditions on kinematic synergy and stability of gait in people with knee osteoarthritis: A study protocol. Adv Biomed Res 2022; 11:35. [PMID: 35720210 PMCID: PMC9201234 DOI: 10.4103/abr.abr_289_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2021] [Revised: 12/21/2021] [Accepted: 12/29/2021] [Indexed: 11/29/2022] Open
Abstract
Background: Knee osteoarthritis (KOA) may considerably change the gait parameters, including the gait variability patterns. Uncontrolled manifold (UCM) analysis has been used to evaluate the relationship between motor control and gait variability as a useful index for assessing the multi-segmental movements’ coordination during walking. To our knowledge, no research has evaluated the alterations in the gait kinematic parameters during normal and narrow path walking in individuals with KOA as compared to asymptomatic people. Materials and Methods: In this cross-sectional study, individuals diagnosed with mild to moderate medial KOA and asymptomatic people will walk at their comfortable preferred speed on a treadmill. A motion capture system will be used to record at least 50 successful gait cycles. The kinematic variability of joints during gait will be analyzed using UCM, with the center of mass (COM) displacement considered as the performance variable. The primary outcome measure will be the lower limb synergy index. Variability of the COM displacement and changes in angles and angular velocities of lower extremity joints will be assessed as the secondary outcomes. Results: The results of this protocol study provide information on the lower limb kinematic synergy during gait on normal and narrow paths for individuals with KOA and asymptomatic controls. Conclusion: This information will help the researchers and clinicians understand KOA patients’ gait variability characteristics more deeply. Moreover, it may lead to an enhanced evidence-based approach for clinical decision-making concerning improving gait stability and decreasing the falling risk in these people.
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Möhler F, Stetter B, Müller H, Stein T. Stride-to-Stride Variability of the Center of Mass in Male Trained Runners After an Exhaustive Run: A Three Dimensional Movement Variability Analysis With a Subject-Specific Anthropometric Model. Front Sports Act Living 2021; 3:665500. [PMID: 34109313 PMCID: PMC8181123 DOI: 10.3389/fspor.2021.665500] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 04/13/2021] [Indexed: 11/24/2022] Open
Abstract
The motion of the human body can be described by the motion of its center of mass (CoM). Since the trajectory of the CoM is a crucial variable during running, one can assume that trained runners would try to keep their CoM trajectory constant from stride to stride. However, when exposed to fatigue, runners might have to adapt certain biomechanical parameters. The Uncontrolled Manifold approach (UCM) and the Tolerance, Noise, and Covariation (TNC) approach are used to analyze changes in movement variability while considering the overall task of keeping a certain task relevant variable constant. The purpose of this study was to investigate if and how runners adjust their CoM trajectory during a run to fatigue at a constant speed on a treadmill and how fatigue affects the variability of the CoM trajectory. Additionally, the results obtained with the TNC approach were compared to the results obtained with the UCM analysis in an earlier study on the same dataset. Therefore, two TNC analyses were conducted to assess effects of fatigue on the CoM trajectory from two viewpoints: one analyzing the CoM with respect to a lab coordinate system (PVlab) and another one analyzing the CoM with respect to the right foot (PVfoot). Full body kinematics of 13 healthy young athletes were captured in a rested and in a fatigued state and an anthropometric model was used to calculate the CoM based on the joint angles. Variability was quantified by the coefficient of variation of the length of the position vector of the CoM and by the components Tolerance, Noise, and Covariation which were analyzed both in 3D and the projections in the vertical, anterior-posterior and medio-lateral coordinate axes. Concerning PVlab we found that runners increased their stride-to-stride variability in medio-lateral direction (1%). Concerning PVfoot we found that runners lowered their CoM (4 mm) and increased their stride-to-stride variability in the absorption phase in both 3D and in the vertical direction. Although we identified statistically relevant differences between the two running states, we have to point out that the effects were small (CV ≤ 1%) and must be interpreted cautiously.
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Affiliation(s)
- Felix Möhler
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Bernd Stetter
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
- Sports Orthopaedics, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Hermann Müller
- Training Science, Department of Sports Science, Justus-Liebig-Universität Giessen, Giessen, Germany
| | - Thorsten Stein
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
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21
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Effects of gait rehabilitation on motor coordination in stroke survivors: an UCM-based approach. Exp Brain Res 2021; 239:2107-2118. [PMID: 33956162 DOI: 10.1007/s00221-021-06117-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 04/17/2021] [Indexed: 10/21/2022]
Abstract
Post-stroke locomotion is usually characterized by asymmetrical gait patterns, compensatory movements of trunk and nonparetic limb, altered motor coordination, and wide inter-stride variability. This pilot study was designed to test a twofold hypothesis: post-stroke survivors can exploit the redundancy of the segmental angles to stabilize the 3D footpath trajectory during the swing phase, in accordance with the Uncontrolled Manifold (UCM) theory; an intense rehabilitative treatment improves both motor performance and outcomes of the UCM analysis. Ten stroke survivors underwent two evaluation sessions, before and after a conventional multidisciplinary intensive rehabilitation program, encompassing clinical tests and gait analysis, both overground and on treadmill. In addition, the UCM analysis was implemented to investigate whether variance of segmental angles is structured to minimize the inter-stride variability of the 3D footpath during the swing phase of treadmill locomotion. Both clinical and spatio-temporal parameters improved after the treatment, even if the statistical significance was reached for a limited set of them. The UCM analysis suggested that post-stroke survivors exploit the redundancy of lower limbs segmental angles mainly during the late swing, without significant differences between affected and unaffected sides. Thereafter, the main significant effects of the rehabilitative treatment consisted in strengthening the synergistic organization of the redundant segmental angles involving a more accurate control of the 3D footpath. Concluding, the UCM theory can be a promising tool to appraise the effects of a specific rehabilitative protocol on motor coordination in post-stroke survivors.
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22
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Yamagata M, Tateuchi H, Shimizu I, Saeki J, Ichihashi N. The relation between kinematic synergy to stabilize the center of mass during walking and future fall risks: a 1-year longitudinal study. BMC Geriatr 2021; 21:240. [PMID: 33849478 PMCID: PMC8045323 DOI: 10.1186/s12877-021-02192-z] [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] [Received: 12/10/2020] [Accepted: 03/31/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Incorrect body weight shifting is a frequent cause of falls, and the control of the whole-body center of mass (CoM) by segmental coordination is essential during walking. Uncontrolled manifold (UCM) analysis is a method of examining the relation between variance in segmental coordination and CoM stability. However, no prospective cohort study has thoroughly investigated how variance in segmental configurations to stabilize the CoM relates to future falls. This study explored whether variance to stabilize the CoM was related to future falls. METHODS At the baseline visit, 30 community-dwelling older adults walked 20 times on a 6-m walkway. Using kinematic data collected during walking by a three-dimensional motion capture system, UCM analysis was performed to investigate how segmental configuration contributes to CoM stability in the frontal plane. One year after the baseline visit, we evaluated whether the subjects experienced falls. Twelve subjects had experienced falls, and 16 had not. Comparisons of variance between older adults with and without falls were conducted by covariate analysis. RESULTS No significant differences in variance were found in the mediolateral direction, whereas in the vertical direction, older adults with fall experiences had a greater variance, reflecting an unstable CoM, than those with no fall experiences. CONCLUSIONS We verified that the high variance in segmental configurations that destabilize the CoM in the vertical direction was related to future falls. The variables of UCM analysis can be useful for evaluating fall risk.
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Affiliation(s)
- Momoko Yamagata
- Graduate School of Human Development and Environment, Kobe University, 3-11 Tsurukabuto, Nada-ku, Kobe, Hyogo, 657-0011, Japan. .,Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto, 606-8507, Japan. .,Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyodaku, Tokyo, 102-0083, Japan.
| | - Hiroshige Tateuchi
- Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto, 606-8507, Japan
| | - Itsuroh Shimizu
- Fukui General Clinic, 1-42-1 Nittazuka, Fukui-shi, Fukui, 910-0067, Japan
| | - Junya Saeki
- Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto, 606-8507, Japan.,Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyodaku, Tokyo, 102-0083, Japan.,Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan
| | - Noriaki Ichihashi
- Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto, 606-8507, Japan
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Kulkarni A, Cho H, Rietdyk S, Ambike S. Step length synergy is weaker in older adults during obstacle crossing. J Biomech 2021; 118:110311. [PMID: 33601182 DOI: 10.1016/j.jbiomech.2021.110311] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 01/31/2021] [Accepted: 02/03/2021] [Indexed: 11/27/2022]
Abstract
Community ambulation requires gait adaptations to navigate environmental obstacles. It is well known that while crossing obstacles, variables quantifying the gait pattern are controlled relative to the obstacle's position. However, the stability of these gait variables is underexplored. We measured foot positions relative to an obstacle as young and older adults stepped over it. We report secondary analysis of this data in which we quantified the stability of the step length when the two feet are placed on either side of the obstacle. We employed the uncontrolled manifold approach to test the hypotheses that (1) synergistic across-trial co-variation in the distances of the front and the back heel from the obstacle edge will stabilize the step length, and (2) older adults will display weaker synergies (i.e., lower step length stability). We observed that the front and back heel distances relative to the obstacle's edge co-varied synergistically to stabilize the step length for both age groups. Therefore, foot placement during obstacle navigation is controlled not only with reference to a feature of the environment (i.e. the obstacle), but also to stabilize the step length, presumably to control COM motion. The synergy index was 38% lower for older adults than young adults. This decline may be associated with aging-related functional deficits and tripping-related falls.
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Affiliation(s)
- Ashwini Kulkarni
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, United States; Center on Aging and the Life Course, Purdue University, West Lafayette, IN, United States
| | - HyeYoung Cho
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, United States; Center on Aging and the Life Course, Purdue University, West Lafayette, IN, United States
| | - Shirley Rietdyk
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, United States; Center on Aging and the Life Course, Purdue University, West Lafayette, IN, United States
| | - Satyajit Ambike
- Department of Health and Kinesiology, Purdue University, West Lafayette, IN, United States; Center on Aging and the Life Course, Purdue University, West Lafayette, IN, United States.
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Jones GD, Jones GL, James DC, Thacker M, Green DA. Identifying consistent biomechanical parameters across rising-to-walk subtasks to inform rehabilitation in practice: A systematic literature review. Gait Posture 2021; 83:67-82. [PMID: 33091746 DOI: 10.1016/j.gaitpost.2020.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 08/07/2020] [Accepted: 10/02/2020] [Indexed: 02/02/2023]
Abstract
BACKGROUND The best approach to rehabilitate the control of everyday whole-body movement (e.g. rise-to-walk) after pathology remains unclear in part because the associated controlled performance variables are not known. Rise-to-walk can be performed fluidly (sit-to-walk) or non-fluidly (sit-to-stand, proceeded by gait-initiation). Biomechanical variables that remain consistent in health regardless of how rise-to walk is performed represent controlled performance variable candidates which could monitor rehabilitative change. RESEARCH QUESTION To determine if any biomechanical parameters remain consistent across rising-to-walk (RTW) subtasks (sit-to-stand, gait-initiation, and sit-to-walk) in healthy adults for purposes of movement control assessment in clinical practice. METHODS Data sources included Medline, Cinahl, and Scopus databases, and the grey literature. Study selection was based on eligibility criteria and must have reported spatiotemporal, kinematic and/or kinetic biomechanical parameters featuring >1 RTW subtask. Data extraction and synthesis; standardised-mean-differences (SMDs) were calculated (pooled if replicated in >1 study) for each parameter. Consistency was determined if SMD95 %CIs included the zero-effect line. RESULTS Nine studies (n = 99) were included (40 ± 7.5yrs). Seven parameters were replicated in >1 study and subjected to meta-analysis (fixed-effect model). Two were consistent between sit-to-stand and sit-to-walk: flexion-momentum time (M(95 %CI) = 0.055(-0.423 to 0.533); p = 0.823) and peak whole-body-centre-of-mass vertical velocity (M(95 %CI)= -0.415(-0.898 to 0.069); p = 0.093); and centre-of-pressure to whole-body-centre-of-mass distance at toe-off (M(95 %CI)= -0.137(-0.712 to 0.439); p = 0.642) between gait-initiation and sit-to-walk. Another 20 parameters were consistent based on single-study SMDs. SIGNIFICANCE Consistent parameters might exist across RTW subtasks. However, the evidence is based on few studies with small samples and variable RTW protocols. Future studies designed to confirm consistency using a standardised RTW protocol are needed.
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Affiliation(s)
- Gareth D Jones
- Centre for Human and Applied Physiological Sciences (CHAPS), Shepherd's House, Guy's Campus, King's College London, London, SE1 1UL, UK; Physiotherapy Department, 3rd Floor Lambeth Wing, St Thomas' Hospital, Westminster Bridge Road, Guy's & St Thomas' NHS Foundation Trust, London, SE1 7EH, UK.
| | - Gareth L Jones
- Physiotherapy Department, 3rd Floor Lambeth Wing, St Thomas' Hospital, Westminster Bridge Road, Guy's & St Thomas' NHS Foundation Trust, London, SE1 7EH, UK.
| | - Darren C James
- Sport and Exercise Science Research Centre, London South Bank University, 103 Borough Road, London, SE1 0AA, UK.
| | - Michael Thacker
- Centre for Human and Applied Physiological Sciences (CHAPS), Shepherd's House, Guy's Campus, King's College London, London, SE1 1UL, UK; Physiotherapy Department, 3rd Floor Lambeth Wing, St Thomas' Hospital, Westminster Bridge Road, Guy's & St Thomas' NHS Foundation Trust, London, SE1 7EH, UK.
| | - David A Green
- Centre for Human and Applied Physiological Sciences (CHAPS), Shepherd's House, Guy's Campus, King's College London, London, SE1 1UL, UK.
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25
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Koh K, Park YS, Park DW, Shim JK. Dance training improves the CNS's ability to utilize the redundant degrees of freedom of the whole body. Sci Rep 2020; 10:22197. [PMID: 33335153 PMCID: PMC7747644 DOI: 10.1038/s41598-020-79081-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 11/30/2020] [Indexed: 11/09/2022] Open
Abstract
Professional dancers demonstrate an amazing ability to control their balance. However, little is known about how they coordinate their body segments for such superior control. In this study, we investigated how dancers coordinate body segments when a physical perturbation is given to their body. A custom-made machine was used to provide a short pulling impulse at the waist in the anterior direction to ten dancers and ten non-dancers. We used Uncontrolled Manifold analysis to quantify the variability in the task-relevant space and task-irrelevant space within the multi-dimensional space made up of individual segments’ centers of mass with a velocity adjustment. The dancers demonstrated greater utilization of redundant degrees of freedom (DoFs) supported by the greater task-irrelevant variability as compared to non-dancers. These findings suggest that long-term specialized dance training can improve the central nervous system’s ability to utilize the redundant DoFs in the whole-body system.
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Affiliation(s)
- Kyung Koh
- Department of Kinesiology, University of Maryland, College Park, MD, USA.,Department of Physical Therapy and Rehabilitation Science, University of Maryland, Baltimore, MD, USA
| | - Yang Sun Park
- Department of Sports Welfare, Korea National University of Transportation, Chungcheongbuk-do, South Korea.
| | - Da Won Park
- Department of Kinesiology, Seoul National University, Seoul, South Korea
| | - Jae Kun Shim
- Department of Kinesiology, University of Maryland, College Park, MD, USA. .,Department of Mechanical Engineering, Kyung Hee University, Yongin-Si, Gyeonggi-do, South Korea. .,Neuroscience and Cognitive Science Program, University of Maryland, College Park, MD, USA. .,Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA.
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26
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Monaco V, Aprigliano F, Lofrumento M, Martelli D, Micera S. Uncontrolled manifold analysis of the effects of a perturbation-based training on the organization of leg joint variance in cerebellar ataxia. Exp Brain Res 2020; 239:501-513. [PMID: 33245386 DOI: 10.1007/s00221-020-05965-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/17/2020] [Indexed: 12/30/2022]
Abstract
Walking patterns of persons affected by cerebellar ataxia (CA) are characterized by wide stride-to-stride variability ascribable to: the background pathology-related sensory-motor noise; the motor redundancy, i.e., an excess of elemental degrees of freedom that overcomes the number of variables underlying a specific task performance. In this study, we first tested the hypothesis that healthy and, especially, CA subjects can effectively exploit solutions in the domain of segmental angles to stabilize the position of either the foot or the pelvis (task performance) across heel strikes, in accordance with the uncontrolled manifold (UCM) theory. Next, we verified whether a specific perturbation-based training allows CA subjects to further take advantage of this coordination mechanism to better cope with their inherent pathology-related variability. Results always rejected the hypothesis of pelvis stabilization whereas supported the idea that the foot position is stabilized across heel strikes by a synergic covariation of elevation and azimuth angles of lower limb segments in CA subjects only. In addition, it was observed that the perturbation-based training involves a decreasing trend in the variance component orthogonal to the UCM in both groups, reflecting an improved accuracy of the foot control. Concluding, CA subjects can effectively structure the wide amount of pathology-related sensory-motor noise to stabilize specific task performance, such as the foot position across heel strikes. Moreover, the promising effects of the proposed perturbation-based training paradigm are expected to improve the coordinative strategy underlying the stabilization of the foot position across strides, thus ameliorating balance control during treadmill locomotion.
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Affiliation(s)
- Vito Monaco
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy.
- Department of Excellence in Robotics&AI, Scuola Superiore Sant'Anna, Pisa, Italy.
| | | | - Margherita Lofrumento
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Neurorehabilitation Sciences, Casa di Cura del Policlinico, Milan, Italy
| | - Dario Martelli
- Department of Mechanical Engineering, The University of Alabama, Tuscaloosa, AL, USA
| | - Silvestro Micera
- The BioRobotics Institute, Scuola Superiore Sant'Anna, Pisa, Italy
- Department of Excellence in Robotics&AI, Scuola Superiore Sant'Anna, Pisa, Italy
- Bertarelli Foundation Chair in Translational NeuroEngineering, Center for Neuroprosthetics and Institute of Bioengineering, School of Engineering, Ecole Polytechnique Federale de Lausanne, Lausanne, Switzerland
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27
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Solnik S, Furmanek MP, Piscitelli D. Movement Quality: A Novel Biomarker Based on Principles of Neuroscience. Neurorehabil Neural Repair 2020; 34:1067-1077. [PMID: 33185150 DOI: 10.1177/1545968320969936] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
A major problem in neurorehabilitation is the lack of objective outcomes to measure movement quality. Movement quality features, such as coordination and stability, are essential for everyday motor actions. These features allow reacting to continuously changing environment or to resist external perturbations. Neurological disorders affect movement quality, leading to functionally impaired movements. Recent findings suggest that the central nervous system organizes motor elements (eg, muscles, joints, fingers) into task-specific ensembles to stabilize motor tasks performance. A method to quantify this feature has been previously developed based on the uncontrolled manifold (UCM) hypothesis. UCM quantifies movement quality in a spatial-temporal domain using intertrial analysis of covariation between motor elements. In this point-of-view article, we first describe major obstacles (eg, the need for group analysis) that interfere with UCM application in clinical settings. Then, we propose a process of quantifying movement quality for a single individual with a novel use of bootstrapping simulations and UCM analysis. Finally, we reanalyze previously published data from individuals with neurological disorders performing a wide range of motor tasks, that is, multi-digit pressing and postural balance tasks. Our method allows one to assess motor quality impairments in a single individual and to detect clinically important motor behavior changes. Our solution may be incorporated into a clinical setting to assess sensorimotor impairments, evaluate the effects of specific neurological treatments, or track movement quality recovery over time. We also recommended the proposed solution to be used jointly with a typical statistical analysis of UCM parameters in cohort studies.
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Affiliation(s)
- Stanislaw Solnik
- University of North Georgia, Dahlonega, GA, USA.,University School of Physical Education in Wroclaw, Wroclaw, Poland
| | - Mariusz P Furmanek
- Northeastern University, Boston, MA, USA.,The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland
| | - Daniele Piscitelli
- McGill University, Montreal, Quebec, Canada.,Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), Laval, Quebec, Canada
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28
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Koch M, Eckardt N, Zech A, Hamacher D. Compensation of stochastic time-continuous perturbations during walking in healthy young adults: An analysis of the structure of gait variability. Gait Posture 2020; 80:253-259. [PMID: 32559644 DOI: 10.1016/j.gaitpost.2020.05.040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 05/15/2020] [Accepted: 05/25/2020] [Indexed: 02/02/2023]
Abstract
BACKGROUND During everyday locomotion, we cope with various internal or external perturbations (e.g. uneven surface). Uncertainty exists on how unpredictable external perturbations increase noise within the motor system and if they are compensated by employing covariation of the limb joints or rather due to decreased sensitivity of an altered posture. RESEARCH QUESTION Do continuous stochastic perturbations affect the structure of gait variability in young and healthy adults? METHODS In a cross-over study, gait kinematics of 21 healthy young sports students were registered during treadmill walking with and without continuous stochastic perturbations. Using the TNC method, the following aspects were analyzed: (a) the sensitivity of body posture to perturbations ('tolerance') decreasing gait variability, (b) the unstructured motor 'noise' increasing gait variability and (c) the amount of 'covariation' of the limb joints. RESULTS Compared to normal walking, gait variability was significantly increased (p < .001) during walking with perturbations. The negative effect of noise was partly compensated by improved 'covariation' of leg joints (p < .001). The aspect 'tolerance' had a small effect on increasing gait variability during stance phase (p < .001) and decreasing gait variability during swing phase (p < .001). SIGNIFICANCE Increased motor noise due to external perturbations is partly compensated by improved covariation of the limb joints. However, the effect of an altered posture slightly affects gait variability. Further studies should focus on different populations (e.g. older participants) to see if they use the same mechanism (improved covariation) to compensate for stochastic perturbations.
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Affiliation(s)
- Monique Koch
- Institute of Sports Science, Friedrich Schiller University of Jena, Jena, Germany.
| | - Nils Eckardt
- Department of Sport and Movement Science, Institute of Sport Science, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany; Department for Exercise & Health, Institute of Sport Science, Leibniz University Hannover, Hannover, Germany.
| | - Astrid Zech
- Institute of Sports Science, Friedrich Schiller University of Jena, Jena, Germany.
| | - Daniel Hamacher
- Institute of Sports Science, Friedrich Schiller University of Jena, Jena, Germany.
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29
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Liu C, Finley JM. Asymmetric gait patterns alter the reactive control of intersegmental coordination patterns in the sagittal plane during walking. PLoS One 2020; 15:e0224187. [PMID: 32437458 PMCID: PMC7241778 DOI: 10.1371/journal.pone.0224187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2019] [Accepted: 04/30/2020] [Indexed: 11/19/2022] Open
Abstract
Recovery from perturbations during walking is primarily mediated by reactive control strategies that coordinate multiple body segments to maintain balance. Balance control is often impaired in clinical populations who walk with spatiotemporally asymmetric gait, and, as a result, rehabilitation efforts often seek to reduce asymmetries in these populations. Previous work has demonstrated that the presence of spatiotemporal asymmetries during walking does not impair the control of whole-body dynamics during perturbation recovery. However, it remains to be seen how the neuromotor system adjusts intersegmental coordination patterns to maintain invariant whole-body dynamics. Here, we determined if the neuromotor system generates stereotypical coordination patterns irrespective of the level of asymmetry or if the neuromotor system allows for variance in intersegmental coordination patterns to stabilize whole-body dynamics in the sagittal plane. Nineteen healthy participants walked on a dual-belt treadmill at a range of step length asymmetries, and they responded to unpredictable, slip-like perturbations. We used principal component analysis of segmental angular momenta to characterize intersegmental coordination patterns before, during, and after imposed perturbations. We found that two principal components were sufficient to explain ~ 95% of the variance in segmental angular momentum during both steady-state walking and responses to perturbations. Our results also revealed that walking with asymmetric step lengths led to changes in intersegmental coordination patterns during the perturbation and during subsequent recovery steps without affecting whole-body angular momentum. These results suggest that the nervous system allows for variance in segment-level coordination patterns to maintain invariant control of whole-body angular momentum during walking. Future studies exploring how these segmental coordination patterns change in individuals with asymmetries that result from neuromotor impairments can provide further insight into how the healthy and impaired nervous system regulates dynamic balance during walking.
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Affiliation(s)
- Chang Liu
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States of America
| | - James M. Finley
- Department of Biomedical Engineering, University of Southern California, Los Angeles, CA, United States of America
- Division of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA, United States of America
- Neuroscience Graduate Program, University of Southern California, Los Angeles, CA, United States of America
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30
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Tomita Y, Turpin NA, Piscitelli D, Feldman AG, Levin MF. Stability of reaching during standing in stroke. J Neurophysiol 2020; 123:1756-1765. [PMID: 32233891 DOI: 10.1152/jn.00729.2019] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Reaching from standing requires simultaneous adjustments of focal and postural task elements. We investigated the ability of people with stroke to stabilize the endpoint trajectory while maintaining balance during standing reaches. Nineteen stroke and 11 age-equivalent healthy subjects reached toward a target (n = 30 trials) located beyond arm length from standing. Endpoint and center-of-mass (COM) trajectories were analyzed using the uncontrolled manifold (UCM) approach, with segment angles as elemental variables. A synergy index (SI) represented the normalized difference between segment angle combinations, leading to endpoint or COM trajectory stabilization (VUCM) and lack of stabilization (in an orthogonal space; VORT). A higher SI reflects greater stability. In both groups, the endpoint SI (SIEND) decreased in parallel with endpoint velocity and returned close to baseline at the end of the movement. The range of SIEND was significantly greater in stroke (median: 0.87; QR:0.54) compared with healthy subjects (median: 0.58; QR: 0.33; P = 0.009). In both groups, the lowest SIEND occurred at the endpoint peak velocity, whereas the minimal SIEND of the stroke group (median: 0.51; QR:0.41) was lower than the healthy group (median: 0.25; QR: 0.50; P = 0.033). The COM SI (SICOM) remained stable in both groups (~0.8). The maintenance of a high SICOM despite a large reduction of SIEND in stroke subjects suggests that kinematic redundancy was effectively used to stabilize the COM position, but less so for endpoint position stabilization. Both focal and postural task elements should be considered when analyzing whole body reaching deficits in patients with stroke.NEW & NOTEWORTHY Reaching from standing requires simultaneous adjustments of endpoint and center-of-mass (COM) positions. We used uncontrolled manifold analysis to investigate the impact of stroke on the ability to use kinematic redundancy in this task. Our results showed that COM position was stabilized, whereas endpoint trajectory was more variable in stroke than healthy subjects. Enhancing the capacity to meet multiple task goals may be beneficial for motor recovery after stroke.
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Affiliation(s)
- Yosuke Tomita
- Department of Physical Therapy, Faculty of Health Care, Takasaki University of Health and Welfare, Takasaki, Gunma, Japan
| | - Nicolas A Turpin
- IRISSE (EA 4075), Department of Sport Sciences (STAPS), University of la Réunion; Tampon, France
| | - Daniele Piscitelli
- School of Physical and Occupational Therapy, McGill University, Montreal, Quebec, Canada.,Centre of the Center for Interdisciplinary Research in Rehabilitation of Greater Montreal, Montreal, Quebec, Canada
| | - Anatol G Feldman
- Centre of the Center for Interdisciplinary Research in Rehabilitation of Greater Montreal, Montreal, Quebec, Canada.,Département de Neurosciences, Université de Montréal, Montreal, Quebec, Canada
| | - Mindy F Levin
- School of Physical and Occupational Therapy, McGill University, Montreal, Quebec, Canada.,Centre of the Center for Interdisciplinary Research in Rehabilitation of Greater Montreal, Montreal, Quebec, Canada
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31
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Möhler F, Marahrens S, Ringhof S, Mikut R, Stein T. Variability of running coordination in experts and novices: A 3D uncontrolled manifold analysis. Eur J Sport Sci 2020; 20:1187-1196. [PMID: 31952460 DOI: 10.1080/17461391.2019.1709561] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The uncontrolled manifold (UCM) approach has been widely used in recent studies to examine variability in daily tasks; however, it has not yet been used to study running or the effects of expertise. Therefore, the aim of this study was to analyse the synergy structure stabilizing the centre of mass (CoM) trajectory in experts compared to novices during running at two different speeds using a subject-specific 3D model. A total of 25 healthy young adults (13 experts, 12 novices) participated in the study. All subjects ran at 10 and 15 km h-1 on a treadmill. In each case, kinematics of 20 consecutive gait cycles were recorded and the effects of expertise and gait cycle phase on the synergy structure were investigated at both speeds. Specifically, the variance affecting the CoM ( U C M ⊥ ) , the variance not affecting the CoM ( U C M ∥ ) , and their ratio ( U C M R a t i o ) were analysed. Descriptively, in both groups there was a synergy stabilizing the CoM trajectory in running. However, the ANOVA showed no differences in U C M R a t i o between the two groups. In novices, U C M ⊥ and U C M ∥ were significantly higher compared to experts at the 15 km h-1 condition. In both groups, there was more variability in the stance phase compared to the flight phase in the majority of cases. The results indicate that experts adopted a more consistent running style. The stride-to-stride variability was diminished but not abolished. This difference was only visible at the 15 km h-1 condition. Furthermore, variability was less constrained in the stance phase compared to the flight phase.
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Affiliation(s)
- Felix Möhler
- BioMotion Centre, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Sonja Marahrens
- BioMotion Centre, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Steffen Ringhof
- BioMotion Centre, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany.,Department of Sport and Sport Science, University of Freiburg, Freiburg, Germany
| | - Ralf Mikut
- Institute for Automation and Applied Informatics (IAI), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Thorsten Stein
- BioMotion Centre, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
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32
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Visual deprivation is met with active changes in ground reaction forces to minimize worsening balance and stability during walking. Exp Brain Res 2020; 238:369-379. [PMID: 31927697 DOI: 10.1007/s00221-020-05722-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 01/02/2020] [Indexed: 10/25/2022]
Abstract
Previous studies suggest that visual information is essential for balance and stability of locomotion. We investigated whether visual deprivation is met with active reactions tending to minimize worsening balance and stability during walking in humans. We evaluated effects of vision on kinetic characteristics of walking on a treadmill-ground reaction forces (GRFs) and shifts in the center of mass (COM). Young adults (n = 10) walked on a treadmill at a comfortable speed. We measured three orthogonal components of GRFs and COM shifts during no-vision (NV) and full-vision (FV) conditions. We also computed the dynamic balance index (DN)-the perpendicular distance from the projection of center of mass (pCOM) to the inter-foot line (IFL) normalized to half of the foot length. Locally weighted regression smoothing with alpha-adjusted serial T tests was used to compare GRFs and DN between two conditions during the entire stance phase. Results showed significant differences in GRFs between FV and NV conditions in vertical and ML directions. Variability of peak forces of all three components of GRF increased in NV condition. We also observed significant increase in DN for NV condition in eight out of ten subjects. The pCOM was kept within BOS during walking, in both conditions, suggesting that body stability was actively controlled by adjusting three components of GRFs during NV walking to minimize stability loss and preserve balance.
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33
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Fettrow T, Reimann H, Grenet D, Thompson E, Crenshaw J, Higginson J, Jeka J. Interdependence of balance mechanisms during bipedal locomotion. PLoS One 2019; 14:e0225902. [PMID: 31800620 PMCID: PMC6892559 DOI: 10.1371/journal.pone.0225902] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Accepted: 11/14/2019] [Indexed: 11/19/2022] Open
Abstract
Our main interest is to identify how humans maintain upright while walking. Balance during standing and walking is different, primarily due to a gait cycle which the nervous system must contend with a variety of body configurations and frequent perturbations (i.e., heel-strike). We have identified three mechanisms that healthy young adults use to respond to a visually perceived fall to the side. The lateral ankle mechanism and the foot placement mechanism are used to shift the center of pressure in the direction of the perceived fall, and the center of mass away from the perceived fall. The push-off mechanism, a systematic change in ankle plantarflexion angle in the trailing leg, results in fine adjustments to medial-lateral balance near the end of double stance. The focus here is to understand how the three basic balance mechanisms are coordinated to produce an overall balance response. The results indicate that lateral ankle and foot placement mechanisms are inversely related. Larger lateral ankle responses lead to smaller foot placement changes. Correlations involving the push-off mechanism, while significant, were weak. However, the consistency of the correlations across stimulus conditions suggest the push-off mechanism has the role of small adjustments to medial-lateral movement near the end of the balance response. This verifies that a fundamental feature of human bipedal gait is a highly flexible balance system that recruits and coordinates multiple mechanisms to maintain upright balance during walking to accommodate extreme changes in body configuration and frequent perturbations.
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Affiliation(s)
- Tyler Fettrow
- Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
- Department of Kinesiology, Temple University, Philadelphia, PA, United States of America
| | - Hendrik Reimann
- Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
- Department of Kinesiology, Temple University, Philadelphia, PA, United States of America
| | - David Grenet
- Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Elizabeth Thompson
- Department of Physical Therapy, University of Delaware, Newark, DE, United States of America
- Department of Kinesiology, Temple University, Philadelphia, PA, United States of America
- Department of Physical Therapy, Temple University, Philadelphia, PA, United States of America
| | - Jeremy Crenshaw
- Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Jill Higginson
- Department of Mechanical Engineering, University of Delaware, Newark, DE, United States of America
| | - John Jeka
- Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States of America
- Department of Kinesiology, Temple University, Philadelphia, PA, United States of America
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34
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Hamacher D, Koch M, Löwe S, Zech A. Less noise during dual-task walking in healthy young adults: an analysis of different gait variability components. Exp Brain Res 2019; 237:3185-3193. [PMID: 31595332 DOI: 10.1007/s00221-019-05664-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Accepted: 10/01/2019] [Indexed: 12/01/2022]
Abstract
Dual-task costs of gait (variability) parameters are frequently used to probe the grade of automaticity of walking. However, recent studies reported contradicting dual-task costs for different gait variability measures within the same cohorts. The effects of a dual-task on the gait pattern are, thus, not fully understood. The aim of the current study was to analyze the different gait variability components ('Tolerance', 'Noise', and 'Covariation') during dual-task walking compared to single-task walking. In an experimental study, 21 young and healthy adults (11 males, 10 females, age: 24 ± 3 years) were included. The participants completed three experimental conditions: (a) single-task walking, (b) dual-task walking (serial-seven subtractions), and (c) cognitive single task in sitting position. To analyze different gait variability components, we applied a method which distinguishes the three components: 'Tolerance', 'Noise', and 'Covariation' (TNC). To test for differences, we used the statistical parametric mapping method. Compared to single-task walking, the results depict lower gait variability of the result parameters during the dual-task condition at 0-15% (p = 0.010) and 94-100% (p = 0.040) of the stance phase and 0-63% (p < 0.001) during the swing phase. The decreased result parameter variability was due to less (sensorimotor) 'Noise' (stance: 2-100%, p < 0.001; swing: 2-59%, p < 0.001) during the dual-task walking condition. In further studies, the sources of the reduced unstructured (sensorimotor) noise in the dual-task condition should be analyzed to better understand the effect of a cognitive dual task on the gait pattern.
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Affiliation(s)
- Daniel Hamacher
- Institute of Sports Science, Friedrich Schiller University of Jena, Seidelstraße 20, 07749, Jena, Germany.
| | - Monique Koch
- Institute of Sports Science, Friedrich Schiller University of Jena, Seidelstraße 20, 07749, Jena, Germany
| | - Susanna Löwe
- Institute of Sports Science, Friedrich Schiller University of Jena, Seidelstraße 20, 07749, Jena, Germany
| | - Astrid Zech
- Institute of Sports Science, Friedrich Schiller University of Jena, Seidelstraße 20, 07749, Jena, Germany
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35
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Pacheco MM, Lafe CW, Newell KM. Search Strategies in the Perceptual-Motor Workspace and the Acquisition of Coordination, Control, and Skill. Front Psychol 2019; 10:1874. [PMID: 31474912 PMCID: PMC6702327 DOI: 10.3389/fpsyg.2019.01874] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 07/30/2019] [Indexed: 01/13/2023] Open
Abstract
In this paper we re-visit and elaborate-on the theoretical framework of learning as searching within the perceptual-motor workspace for a solution to the task. The central focus is the nature of search strategies to locate and create stable equilibrium regions in the perceptual-motor workspace and how these strategies relate to the emergent movement forms in the acquisition of coordination, control, and skill. In the ecological theory of perception and action, the enhanced stability of performance occurs through the attunement of the perceptual systems to the task dynamics together with modifications of action as task and intrinsic dynamics cooperate and/or compete. Thus, through practice in this search process, individuals adapt to the pick-up of task relevant perceptual variables and change their movement form according to the stability of the performed action and its outcome in relation to the task demands. Contemporary experimental findings have revealed features of the search process given the interaction of individual intrinsic dynamics in the context of task requirements and principles that drive the change – e.g., exploitation of more tolerant task-space solutions and emergence of compensatory mechanisms. Finally, we outline how the search strategy framework relates to traditional learning-related phenomena: including the dynamical pathways of learning, learning curves, factors of learning, individuality, motor development, and sport and rehabilitation interventions.
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Affiliation(s)
- Matheus M Pacheco
- Motor Behavior Laboratory (LACOM), School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil
| | - Charley W Lafe
- Motor Behavior Laboratory, Department of Kinesiology, University of Georgia, Athens, GA, United States
| | - Karl M Newell
- Motor Behavior Laboratory, Department of Kinesiology, University of Georgia, Athens, GA, United States
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Center of mass in analysis of dynamic stability during gait following stroke: A systematic review. Gait Posture 2019; 72:154-166. [PMID: 31202025 DOI: 10.1016/j.gaitpost.2019.06.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Revised: 05/27/2019] [Accepted: 06/07/2019] [Indexed: 02/02/2023]
Abstract
BACKGROUND The Center of mass (CoM) analysis reveals important aspects of gait dynamic stability of stroke patients, but the variety of methods and measures represents a challenge for planning new studies. RESEARCH QUESTION How have the CoM measures been calculated and employed to investigate gait stability after a stroke? Three issues were addressed: (i) the methodological aspects of the calculation of CoM measures; (ii) the purposes and (iii) the conclusions of the studies on gait stability that employed those measures. METHODS PubMed and Science Direct databases have been searched to collect original articles produced until July 2017. A set of 26 studies were selected according to criteria involving their methodological quality. RESULTS A compromise between accuracy and feasibility in CoM calculation could be reached using the segmental method with 7-9 segments. Regarding their purposes, two types of studies were identified: clinical and research oriented. From the first ones, we highlighted: the margin of stability (MoS) in the mediolateral (ML) direction, and the angular momentum in the frontal plane could be indicators of dynamical stability; the MoS in the anteroposterior (AP) direction might be able to detect the risk of falls and the symmetry of vertical CoM displacement could be used to analyze energy expenditure during gait. These and other CoM measures are potentially useful in clinical settings, but their psychometric properties are still to be determined. The research oriented studies allowed to clarify that stability is not improved by widening the step in stroke patients and that the impaired control of the non-paretic limb might be the main source of instability. SIGNIFICANCE This review provides recommendations on the methods for estimating CoM and its measures, identifies the potential usefulness of CoM parameters and indicates issues that could be addressed in future studies.
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Yamagata M, Tateuchi H, Shimizu I, Saeki J, Ichihashi N. The relation between limb segment coordination during walking and fall history in community-dwelling older adults. J Biomech 2019; 93:94-100. [PMID: 31272683 DOI: 10.1016/j.jbiomech.2019.06.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 06/17/2019] [Accepted: 06/17/2019] [Indexed: 11/28/2022]
Abstract
Control of the swing foot during walking is important to prevent falls. The trajectories of the swing foot are adjusted by coordination of the lower limbs, which is evaluated with uncontrolled manifold (UCM) analysis. A previous study that applied this analysis to walking revealed that older adults with fall history had compensatorily great segment coordination to stabilize the swing foot during normal walking. However, it is unknown whether the increase in segment coordination helps for preventing incident falls in the future. At baseline measurement, 30 older adults walked for 20 times at a comfortable speed. UCM analysis was performed to evaluate how the segment configuration in the lower limbs contributes to the swing foot stability. One year after the baseline visit, we asked the subjects if there were incident falls through a questionnaire. The univariate and multivariable logistic regression analyses were performed to assess the association between the index of segment coordination and incident falls with and without adjustment for gait velocity. Twenty-eight older adults who responded to the questionnaire were classified into older adults (n = 12) who had the incident fall and those (n = 16) who did not have falls. It was revealed that older adults who increased the segment coordination associated with swing foot stability tended to experience at least one fall within one year of measurement. The index of the UCM analysis can be a sensitive predictor of incident falls.
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Affiliation(s)
- Momoko Yamagata
- Human Health Science, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507, Japan; Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyodaku, Tokyo 102-0083, Japan.
| | - Hiroshige Tateuchi
- Human Health Science, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507, Japan
| | - Itsuroh Shimizu
- Fukui General Clinic, 1-42-1 Nittazuka, Fukui-shi, Fukui 910-0067, Japan
| | - Junya Saeki
- Faculty of Sport Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama 359-1192, Japan; Research Fellow of the Japan Society for the Promotion of Science, 5-3-1 Kojimachi, Chiyodaku, Tokyo 102-0083, Japan
| | - Noriaki Ichihashi
- Human Health Science, Graduate School of Medicine, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo, Kyoto 606-8507, Japan
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Martin V, Reimann H, Schöner G. A process account of the uncontrolled manifold structure of joint space variance in pointing movements. BIOLOGICAL CYBERNETICS 2019; 113:293-307. [PMID: 30771072 PMCID: PMC6510836 DOI: 10.1007/s00422-019-00794-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 02/05/2019] [Indexed: 06/09/2023]
Abstract
In many situations, the human movement system has more degrees of freedom than needed to achieve a given movement task. Martin et al. (Neural Comput 21(5):1371-1414, 2009) accounted for signatures of such redundancy like self-motion and motor equivalence in a process model in which a neural oscillator generated timed end-effector virtual trajectories that a neural dynamics transformed into joint virtual trajectories while decoupling task-relevant and task-irrelevant combinations of joint angles. Neural control of muscle activation and the biomechanical dynamics of the arm were taken into account. The model did not address the main signature of redundancy, however, the UCM structure of variance: Many experimental studies have shown that across repetitions, variance of joint configuration trajectories is structured. Combinations of joint angles that affect task variables (lying in the uncontrolled manifold, UCM) are much more variable than combinations of joint angles that do not. This finding has been robust across movement systems, age, and tasks and is often preserved in clinical populations as well. Here, we provide an account for the UCM structure of variance by adding four types of noise sources to the model of Martin et al. (Neural Comput 21(5):1371-1414, 2009). Comparing the model to human pointing movements and systematically examining the role of each noise source and mechanism, we identify three causes of the UCM effect, all of which, we argue, contribute: (1) the decoupling of motor commands across the task-relevant and task-irrelevant subspaces together with "neural" noise at the level of these motor commands; (2) "muscle noise" combined with imperfect control of the limb; (3) back-coupling of sensed joint configurations into the motor commands which then yield to the sensed joint configuration within the UCM.
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Affiliation(s)
- Valère Martin
- Institute for Neural Computation, Ruhr-University, Bochum, Germany
- Present Address: Bern University of Applied Sciences, Länggasse 85, 3052 Zollikofen, Switzerland
| | - Hendrik Reimann
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE USA
| | - Gregor Schöner
- Institute for Neural Computation, Ruhr-University, Bochum, Germany
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Diss C, Vicinanza D, Smith L, Williams GKR. Lower limb tri-joint synchrony during running gait: A longitudinal age-based study. Hum Mov Sci 2019; 66:301-309. [PMID: 31132587 DOI: 10.1016/j.humov.2019.05.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 04/10/2019] [Accepted: 05/13/2019] [Indexed: 11/17/2022]
Abstract
Biomechanical research exploring the age-based mechanics of running gait can provide valuable insight into the reported decline in master endurance running performance. However, few studies have shown consistent biomechanical differences in the gait of trained distance runners compared to their younger counterparts. It might be that differences occur in the interaction between joints. The aim was to explore the differences in tri-joint synchrony of the lower limb, quantified through cluster phase analysis, of runners at 50 years of age compared to seven years later. Cluster phase analysis was used to examine changes in synchrony between 3 joints of the lower limb during the stance phase of running. Ten male, endurance-trained athletes M50 (age = 53.54 ± 2.56 years, mass = 71.05 ± 7.92 kg) participated in the study and returned after seven years M57 (age = 60.49 ± 2.56 years, mass = 69.08 ± 8.23 kg). Lower limb kinematics (Vicon, 120 Hz) and ground reaction forces (Kistler, 1080 Hz) were collected as participants performed multiple trials at a horizontal running velocity = 3.83 ± 0.40 m·s-1 over the force plate. Significant increase (31%) in rate of force development in the absorption phase, and significantly reduced sagittal plane knee joint range of motion (30.50 v 23.68°) were found following the seven years of ageing. No further discrete single joint measures were significantly different between M50 and M57. Joint synchrony between the hip, knee and ankle was significantly higher at M57 compared to M50 during the absorption phase of stance. The force attenuation strategy is compromised after seven years of ageing, which is associated with more synchronous movements in the lower limb joints. Increased joint synchrony as a function of age could be a mechanism associated with this key injury provoking phase of running gait.
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Affiliation(s)
- Ceri Diss
- Department of Life Sciences, University of Roehampton, London, UK.
| | - Domenico Vicinanza
- School of Computing and Information Science, Anglia Ruskin University, Cambridge, UK.
| | - Lee Smith
- Cambridge Centre for Sport and Exercise Sciences, Anglia Ruskin University, Cambridge, UK.
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Stroke survivors exhibit stronger lower extremity synergies in more challenging walking conditions. Exp Brain Res 2019; 237:1919-1930. [PMID: 31106386 DOI: 10.1007/s00221-019-05560-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Accepted: 05/11/2019] [Indexed: 10/26/2022]
Abstract
The aim of this study was to examine how kinematic synergies are utilised as compensatory movements to stabilise foot positions under different walking task constraints in people with stroke. Ten (Males = 6, Females = 4) hemiplegic chronic stroke survivors volunteered to participate in this study, recruited from a rehabilitation centre. They completed a consent form and participated in treadmill walking tasks; flat, uphill, and crossing over a moving obstacle. The uncontrolled manifold method was used to quantify kinematic synergies in the paretic and non-paretic legs during their swing phase. The results of this study showed the strength of synergies was significantly greater in the obstacle task than in the uphill walking tasks at mid and terminal swing phases. In conclusion, the results suggest that walking in the challenging situations caused people with stroke to control step stability with greater compensation between lower extremity joints. Participants adapted to the increased challenge by increasing the amount of 'good variability', which could be a strategy to reduce the risks of falling.
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41
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Möhler F, Ringhof S, Debertin D, Stein T. Influence of fatigue on running coordination: A UCM analysis with a geometric 2D model and a subject-specific anthropometric 3D model. Hum Mov Sci 2019; 66:133-141. [PMID: 30981149 DOI: 10.1016/j.humov.2019.03.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Revised: 03/19/2019] [Accepted: 03/25/2019] [Indexed: 10/27/2022]
Abstract
Although fatigue is a central issue in endurance sports little is known about the effects of fatigue on coordination. The uncontrolled manifold (UCM) approach has been widely used in recent studies to examine coordination in human movement; however, it has not been used to study the effects of fatigue on running. Therefore, the aim of this study was to analyze the effects of fatigue on the synergy structure stabilizing the center of mass (CoM) trajectory in experienced runners during high-intensity running using the UCM approach. A total of 13 healthy young experienced runners participated in the study. Based on a lactate threshold testing undertaken one week prior to the measurements, participants were asked to run on a treadmill at their individual "fatigue-speed" until exhaustion. The kinematics of 20 consecutive gait cycles were recorded at the beginning (rested) and at the end (fatigue) of the protocol. The effects of fatigue on the synergy structure were investigated using a geometric 2D model and a subject-specific anthropometric 3D model. Specifically, the variance affecting the CoM trajectory (UCM⊥), the variance not affecting the CoM trajectory (UCM‖), and their ratio (UCMRatio) were analyzed for different gait cycle phases (absorption, propulsion and flight phase). Three-way repeated-measures ANOVA tests revealed differences between the two models. Fatigue-induced changes in the UCM structure could only be detected using the 3D model. UCMRatio did not change, but UCM⊥ increased during flight phase. In the 2D model, UCMRatio and both components were higher during the propulsion phase than during the absorption phase in both the rested and the fatigued state. Using a current concept for analyzing motor coordination, the UCM approach, only minor changes with fatigue were detected using the 3D subject-specific model. This indicates that the runners were able to control the trajectory of their CoM when fatigued. As the 2D model was not able to detect these changes, our study emphasizes that future studies on the effects of fatigue should focus on 3D analyses.
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Affiliation(s)
- Felix Möhler
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany.
| | - Steffen Ringhof
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Daniel Debertin
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Thorsten Stein
- BioMotion Center, Institute of Sports and Sports Science (IfSS), Karlsruhe Institute of Technology, Karlsruhe, Germany
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Martino G, Ivanenko Y, Serrao M, Ranavolo A, Draicchio F, Casali C, Lacquaniti F. Locomotor coordination in patients with Hereditary Spastic Paraplegia. J Electromyogr Kinesiol 2019; 45:61-69. [PMID: 30836301 DOI: 10.1016/j.jelekin.2019.02.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 02/14/2019] [Accepted: 02/18/2019] [Indexed: 10/27/2022] Open
Abstract
Locomotion is a complex behaviour that requires the coordination of multiple body segments and muscle groups. Here we investigated how the weakness and spasticity in individuals with Hereditary Spastic Paraplegia (HSP) affect the coordination patterns of the lower limbs. We analysed kinematics and electromyographic (EMG) activity from 12 leg muscles in 21 persons with HSP and 20 control subjects at matched walking speeds. To assess the locomotor coordination, we examined the covariation between thigh, shank and foot elevation angles by means of principal component analysis and the modular organization of EMG patterns using the non-negative matrix factorization algorithm. The characteristic features of the HSP gait consisted in changes of the elevation angles covariation, the shape of the gait loop, reduced range of motion of the distal segments and significantly lower foot lift. The EMG factorization analysis revealed a comparable structure of the motor output between HSP and control groups, but significantly wider basic temporal patterns associated with muscles innervated from the sacral spinal segments in HSP. Overall, the applied methodology highlighted the impact of the corticospinal degeneration and spasticity on the coordination of distal limb segments and basic muscle modules associated with distal spinal segments.
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Affiliation(s)
- G Martino
- Centre of Space Bio-medicine, University of Rome Tor Vergata, 00133 Rome, Italy; Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy.
| | - Y Ivanenko
- Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy
| | - M Serrao
- Rehabilitation Centre Policlinico Italia, 00162 Rome, Italy; Department of Medical and Surgical Sciences and Biotechnologies, Sapienza University of Rome, 04100 Latina, Italy
| | - A Ranavolo
- INAIL, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, Monte Porzio Catone, 00078 Rome, Italy
| | - F Draicchio
- INAIL, Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, Monte Porzio Catone, 00078 Rome, Italy
| | - C Casali
- Department of Medical and Surgical Sciences and Biotechnologies, Sapienza University of Rome, 04100 Latina, Italy
| | - F Lacquaniti
- Centre of Space Bio-medicine, University of Rome Tor Vergata, 00133 Rome, Italy; Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, 00179 Rome, Italy; Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy
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Rosenblatt NJ, Hurt CP. Recommendation for the minimum number of steps to analyze when performing the uncontrolled manifold analysis on walking data. J Biomech 2019; 85:218-223. [PMID: 30718066 DOI: 10.1016/j.jbiomech.2019.01.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 01/07/2019] [Accepted: 01/08/2019] [Indexed: 01/08/2023]
Abstract
The uncontrolled manifold (UCM) analysis quantifies the extent to which co-variation among a set of variables facilitates consistent performance by partitioning variance in those variables into two components then calculating their normalized difference (i.e., the synergy index). Although UCM-derived measures are thought to depend on the number of data points analyzed, the minimum number needed to reasonably approximate true values of these measures is unknown. For each of two performance variables related to mechanical stability of gait, we evaluated changes in UCM-derived measures when increasing the number of analyzed points, here steps. Fourteen older adults walked on a treadmill while motion capture tracked movement. For each subject, n steps (where n = 2-99) were randomly sampled from the first 100, then used to calculate UCM-derived variables. For each subject, variables were expressed as a percent of the subject-specific value with n = 100 and averaged across 50 simulations. For each n, 95% confidence intervals (CIs) were calculated from group data. The minimum number of steps to "reasonably approximate" a variables was defined as the value of n for which the lower CI was >90% of the value with n = 100. Regardless of performance variable, reasonable approximations of the synergy index were attained with n = 16 steps, whereas n = 50 steps were needed for each of the variance components However, the differences between using 16 steps and 50 steps were small. Collecting 15-20 steps is recommended for a reasonable approximation of the synergy indices considered herein, particularly when data collection is constrained to a limited number of steps.
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Affiliation(s)
- Noah J Rosenblatt
- Rosalind Franklin University of Medicine and Science, Center for Lower Extremity Ambulatory Research (CLEAR) at the Dr. William M. Scholl College of Podiatric Medicine, 3333 Greenbay Road, North Chicago, IL 60064, United States.
| | - Christopher P Hurt
- University of Alabama at Birmingham, Department of Physical Therapy, United States
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The effects of fall history on kinematic synergy during walking. J Biomech 2019; 82:204-210. [DOI: 10.1016/j.jbiomech.2018.10.032] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 10/09/2018] [Accepted: 10/23/2018] [Indexed: 11/18/2022]
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Shafizadeh M, Crowther R, Wheat J, Davids K. Effects of personal and task constraints on limb coordination during walking: A systematic review and meta-analysis. Clin Biomech (Bristol, Avon) 2019; 61:1-10. [PMID: 30415107 DOI: 10.1016/j.clinbiomech.2018.10.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 07/25/2018] [Accepted: 10/30/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND In human behaviour, emergence of movement patterns is shaped by different, interacting constraints and consequently, individuals with motor disorders usually display distinctive lower limb coordination modes. OBJECTIVES To review existing evidence on the effects of motor disorders and different task constraints on emergent coordination patterns during walking, and to examine the clinical significance of task constraints on gait coordination in people with motor disorders. METHODS The search included CINHAL Plus, MEDLINE, HSNAE, SPORTDiscus, Scopus, Pubmed and AMED. We included studies that compared intra-limb and inter-limb coordination during gait between individuals with a motor disorder and able-bodied individuals, and under different task constraints. Two reviewers independently examined the quality of studies by using the Newcastle Ottawa Scale-cohort study. FINDINGS From the search results, we identified 1416 articles that studied gait patterns and further analysis resulted in 33 articles for systematic review and 18 articles for meta-analysis-1, and 10 articles for meta-analysis-2. In total, the gait patterns of 539 patients and 358 able-bodied participants were analysed in the sampled studies. Results of the meta-analysis for group comparisons revealed a low effect size for group differences (ES = -0.24), and a moderate effect size for task interventions (ES = -0.53), on limb coordination during gait. INTERPRETATION Findings demonstrated that motor disorders can be considered as an individual constraint, significantly altering gait patterns. These findings suggest that gait should be interpreted as functional adaptation to changing personal constraints, rather than as an abnormality. Results imply that designing gait interventions, through modifying locomotion tasks, can facilitate the emergent re-organisation of inter-limb coordination patterns during rehabilitation.
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Affiliation(s)
| | - Robert Crowther
- School of Health Sciences, University of South Australia, Australia
| | - Jonathan Wheat
- Faculty of Health and Wellbeing, Sheffield Hallam University, UK
| | - Keith Davids
- Centre for Sport Engineering Research, Sheffield Hallam University, UK
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Eckardt N, Rosenblatt NJ. Healthy aging does not impair lower extremity motor flexibility while walking across an uneven surface. Hum Mov Sci 2018; 62:67-80. [DOI: 10.1016/j.humov.2018.09.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 07/16/2018] [Accepted: 09/15/2018] [Indexed: 02/06/2023]
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47
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Kao PC, Srivastava S. Mediolateral footpath stabilization during walking in people following stroke. PLoS One 2018; 13:e0208120. [PMID: 30496257 PMCID: PMC6264822 DOI: 10.1371/journal.pone.0208120] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 11/12/2018] [Indexed: 02/03/2023] Open
Abstract
Community dwelling stroke survivors most often fall while walking. Understanding how post-stroke individuals control mediolateral footpath during walking may help elucidate the mechanisms that contribute to walking instability. By applying the Uncontrolled Manifold (UCM) approach, we investigated (1) how post-stroke individuals coordinate lower-extremity joint motions to stabilize mediolateral footpath of the swing leg, and (2) how the inter-joint coordination in footpath stabilization correlates to their walking stability. Nine stroke subjects and nine healthy controls walked on a treadmill at four different speeds. UCM analysis partitions the variance of kinematic configurations across gait cycles into "good variance" (i.e., the variance component leading to a consistent footpath) or "bad variance" (i.e., the variance component leading to an inconsistent footpath). We found that both groups had a significantly greater "good" than "bad" variance (p<0.05) for most of the swing phase, suggesting that mediolateral footpath is an important variable stabilized by the central nervous system during walking. Stroke subjects had significantly greater relative variance difference (ΔV) (i.e. normalized difference between "good" and "bad" variance) (p<0.05), indicating a stronger kinematic synergy in footpath stabilization, than the controls. In addition, the kinematic synergy in mediolateral footpath stabilization is strongest during mid-swing but weakest during late swing in healthy gait. However, this phase-dependent strategy is preserved for mid-swing but not for late swing in stroke gait. Moreover, stroke and healthy subjects demonstrated different relationships between UCM and walking stability measures. A stronger kinematic synergy in healthy gait is associated with better walking stability whereas having more "good variance" or stronger kinematic synergy in stroke gait is associated with less walking stability. The current findings suggest that walking with too much "good variance" in people following stroke, despite no effect on the footpath, may adversely affect their walking stability to some extent.
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Affiliation(s)
- Pei-Chun Kao
- Department of Physical Therapy, University of Massachusetts Lowell, Lowell, Massachusetts, United States of America
- * E-mail:
| | - Shraddha Srivastava
- Department of Health Sciences and Research, Medical University of South Carolina, Charleston, South Carolina, United States of America
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Sun D, Fekete G, Mei Q, Gu Y. The effect of walking speed on the foot inter-segment kinematics, ground reaction forces and lower limb joint moments. PeerJ 2018; 6:e5517. [PMID: 30155372 PMCID: PMC6109584 DOI: 10.7717/peerj.5517] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 08/06/2018] [Indexed: 12/03/2022] Open
Abstract
Background Normative foot kinematic and kinetic data with different walking speeds will benefit rehabilitation programs and improving gait performance. The purpose of this study was to analyze foot kinematics and kinetics differences between slow walking (SW), normal walking (NW) and fast walking (FW) of healthy subjects. Methods A total of 10 healthy male subjects participated in this study; they were asked to carry out walks at a self-selected speed. After measuring and averaging the results of NW, the subjects were asked to perform a 25% slower and 25% faster walk, respectively. Temporal-spatial parameters, kinematics of the tibia (TB), hindfoot (HF), forefoot (FF) and hallux (HX), and ground reaction forces (GRFs) were recorded while the subjects walked at averaged speeds of 1.01 m/s (SW), 1.34 m/s (NW), and 1.68 m/s (FW). Results Hindfoot relative to tibia (HF/TB) and forefoot relative to hindfoot (FF/HF) dorsiflexion (DF) increased in FW, while hallux relative to forefoot (HX/FF) DF decreased. Increased peak eversion (EV) and peak external rotation (ER) in HF/TB were observed in FW with decreased peak supination (SP) in FF/HF. GRFs were increased significantly with walking speed. The peak values of the knee and ankle moments in the sagittal and frontal planes significantly increased during FW compared with SW and NW. Discussion Limited HF/TB and FF/HF motion of SW was likely compensated for increased HX/FF DF. Although small angle variation in HF/TB EV and FF/HF SP during FW may have profound effects for foot kinetics. Higher HF/TB ER contributed to the FF push-off the ground while the center of mass (COM) progresses forward in FW, therefore accompanied by higher FF/HF abduction in FW. Increased peak vertical GRF in FW may affected by decreased stance duration time, the biomechanical mechanism maybe the change in vertical COM height and increase leg stiffness. Walking speed changes accompanied with modulated sagittal plane ankle moments to alter the braking GRF during loading response. The findings of foot kinematics, GRFs, and lower limb joint moments among healthy males may set a reference to distinguish abnormal and pathological gait patterns.
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Affiliation(s)
- Dong Sun
- Faculty of Sports Science, Ningbo University, Ningbo, China.,Faculty of Engineering, University of Pannonia, Veszprem, Hungary.,Savaria Institute of Technology, Eötvös Lorand University, Szombathely, Hungary
| | - Gusztáv Fekete
- Faculty of Engineering, University of Pannonia, Veszprem, Hungary.,Savaria Institute of Technology, Eötvös Lorand University, Szombathely, Hungary
| | - Qichang Mei
- Faculty of Sports Science, Ningbo University, Ningbo, China.,Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Yaodong Gu
- Faculty of Sports Science, Ningbo University, Ningbo, China.,Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
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Hamacher D, Zech A. Development of functional variability during the motor learning process of a complex cyclic movement. J Biomech 2018; 77:124-130. [PMID: 30049449 DOI: 10.1016/j.jbiomech.2018.07.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Revised: 06/14/2018] [Accepted: 07/04/2018] [Indexed: 11/18/2022]
Abstract
Traditionally, movement variability is considered an indicator for sensorimotor malfunctioning. However, functional movement variability is also a result of compensation mechanisms e.g. to account for prior movement deviations and is, therefore, crucial for stable movements. The aim of this study was to analyze functional variability during motor learning of a complex cyclic task. Thirteen young participants practised riding a Pedalo® slalom until they were able to complete the task without errors. Since trunk movements are controlled with high priority, we analyzed trunk kinematics as a result parameter. Since lower extremities affect the result parameter, foot, thigh and pelvis kinematics are considered execution parameters. The movement variability for result and execution parameters was determined for the first (poor performance), an intermediate (medium performance) and the last (good performance) training sessions. Furthermore, the variability ratio (execution/result parameter) was calculated as a measure of functional variability. Movement variability of the result parameter decreased significantly with increasing expertise. In contrast, movement variability of all execution parameters increased significantly from measurements representing poor to medium performance. No change from medium to good performance was found. Functional variability increased over time in all execution parameters. Since the movement variability of all execution parameters did not decrease with increasing Pedalo performance, applying a traditional interpretation approach of movement variability would have led to completely wrong conclusions. Possible mechanisms explaining the increased movement variability are discussed. The variability ratio seems to be the only parameter that can reveal improved sensorimotor functioning during all analyzed stages of motor learning.
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Affiliation(s)
- Daniel Hamacher
- Institute of Sport Science, Friedrich Schiller University of Jena, Seidelstraße 20, 07749 Jena, Germany.
| | - Astrid Zech
- Institute of Sport Science, Friedrich Schiller University of Jena, Seidelstraße 20, 07749 Jena, Germany.
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Tokuda K, Anan M, Takahashi M, Sawada T, Tanimoto K, Kito N, Shinkoda K. Biomechanical mechanism of lateral trunk lean gait for knee osteoarthritis patients. J Biomech 2018; 66:10-17. [DOI: 10.1016/j.jbiomech.2017.10.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 10/04/2017] [Accepted: 10/15/2017] [Indexed: 10/18/2022]
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