A Potential Wearable for Post-stroke Rehabilitation

Overview

Participants are seeking to unleash the full therapeutic potential of a newly developed, customizable and potentially commericializable 10-channel Functional Electrical Stimulation (FES) to rehabilitate the gait of chronic stroke survivors. Each subject will undergo 18-sessions (~1 month) FES training. Participants will utilize the theory of muscle synergies from motor neurosciences, which are defined as neural modules of motor control that coordinate the spatiotemporal activation patterns of multiple muscles, to guide our personal selections of muscles for FES. It is hypothesized that chronic stroke survivors will learn from FES stimulations, over several daily sessions, both by suppressing the original abnormal muscle synergies and by employing the normal muscle synergies as specified in the FES. It is also expected that the walk synergies of the paretic side of chronic stroke survivors should be more similar to healthy muscle synergies at the two post-training time points than before training.

Full Title of Study: “A Wearable for Post-stroke Rehabilitative Multi-muscle Stimulation Inspired by the Natural Organization of Neuromuscular Control”

Study Type

  • Study Type: Interventional
  • Study Design
    • Allocation: Non-Randomized
    • Intervention Model: Single Group Assignment
    • Primary Purpose: Treatment
    • Masking: None (Open Label)
  • Study Primary Completion Date: March 23, 2024

Detailed Description

Stroke is one of the leading causes of long-term adult disability worldwide. The impaired ability to walk post-stroke severely limits mobility and quality of life. Many recently-developed assistive technologies for gait rehabilitation are at present only marginally better at best than traditional therapies in their efficacies. There is an urgent need of novel, clinically viable, and effective gait rehabilitative strategies that can provide even better functional outcome for stroke survivors with diverse presentations. Among the many new post-stroke interventions, functional electrical stimulation (FES) of muscles remains attractive. FES is a neural-rehabilitative technology that communicates control signals from an external device to the neuromuscular system. There is increasing recognition that rehabilitation paradigms should promote restitution of the patient's muscle coordination towards the normal pattern during training, and FES can achieve this goal when stimulations are applied to the set of muscles whose natural coordination is impaired. For this reason, FES is a very promising interventional strategy. Existing FES paradigms, however, have yielded ambiguous results in previous clinical trials, especially those for chronic survivors, likely because either stimulations were applied only to single or a few muscles, or the stimulation pattern did not mimic the natural muscle coordination pattern during gait. A multi-muscle FES, when applied to a larger functional set of muscles and driven by their natural coordination pattern, can guide muscle activations towards the normal pattern through neuroplasticity, thus restore impairment at the level of muscle-activation deficit. The first aim of our project is to utilize a 8-channel FES wearable for delivering multi-muscle FES to muscles in the lower-limb muscles. Participants will attempt to rehabilitate the gait of chronic stroke survivors over 12 training sessions by delivering stimulations to multiple muscles, in their natural coordination pattern, using our wearable. As such, participants will utilize the theory of muscle synergy from motor neuroscience to guide our personalizable selections of muscles for FES. Muscle synergies are hypothesized neural modules of motor control that coordinate the spatiotemporal activation patterns of multiple muscles. Our customizable FES pattern for each stroke survivor will be constructed based on the normal muscle synergies that are absent in the stroke survivor's muscle pattern during walking. Since muscle synergies represent the natural motor-control units used by the nervous system, reinforcement of their activations through FES should lead to restoration of normal neuromuscular coordination, thus more natural post-training gait. Our second aim is to evaluate the effectiveness of our FES paradigm by assessing the walk-muscle synergies in the paretic and non-paretic legs of the trained stroke survivors, before, after, and 1 month following our intervention. In doing so, participants hope to explore whether lower-limb muscle synergy can be a physiologically-based marker of motor impairment for stroke survivors. If our muscle-synergy-based multi-muscle FES is indeed efficacious, our strategy will help many disabled chronic stroke survivors to regain mobility, thus living with a much higher quality of life in the decades to come. The clinical and societal impact of our research will be huge.

Interventions

  • Device: A functional electrical stimulation device for post-stroke rehabilitation
    • Most of the FDA-approved commercial FES devices deliver therapy that targets specific kinematic impairment in the step cycle (e.g., foot drop). Our device will be unique in that it can stimulate many muscles around multiple joints for a more comprehensive and naturalistic restoration of lower-limb motor functions.

Arms, Groups and Cohorts

  • Experimental: Delivering FES to stroke survivors
    • In stroke survivors, normal and abnormal muscle synergies will also be determined from their walk EMGs. Our proposed FES intervention involves delivering stimulations to muscles with waveforms generated from the activations of all the normal synergies not observed in each stroke survivor. We are going to employ the wearable to deliver personalized muscle-synergy-based FES stimulations to multiple groups of leg muscles on the stroke-affected side of elderly chronic stroke survivors as they walk on a treadmill/overground for gait rehabilitation. We hypothesized that the subject will essentially be walking with his/her abnormal muscle pattern superimposed with the artificially introduced “normal” muscle pattern coming from FES.
  • Experimental: Delivery no current FES to stroke survivors (Sham group)
    • In stroke survivors, normal and abnormal muscle synergies will also be determined from their walk EMGs. Our proposed FES intervention involves delivering stimulations to muscles with waveforms generated from the activations of all the normal synergies not observed in each stroke survivor. Additionally, we are going to introduce a sham group. We are going to employ the wearable to multiple groups of leg muscles on the stroke-affected side of elderly chronic stroke survivors without any stimulation as they walk on a treadmill or overground for gait rehabilitation. The purpose of the sham group is to empirically validate the effectiveness of the FES wearable.

Clinical Trial Outcome Measures

Primary Measures

  • Surface electromyographic signals from up to 14 muscles on the paretic and non-paretic side during gait.
    • Time Frame: The assessment will be performed at baseline
    • To assess the muscle synergies, surface EMGs will be recorded from 14 muscles (tibialis anterior (TA), medical gastrocnemius (MG), soleus (SOL), vastus medialis (VM), rectus femoris (RF), hamstrings (HAM), adductor longus (AL), gluteus maximus (GM) lateral gastrocnemius (LG), vastus lateralis (VL), tensor fasciae latae (TFL), erector spinae (ES), external oblique (EO), and latissimus dorsi (LatDor)), using a wireless EMG system (Delsys; 2000 Hz). All electrodes will be securely attached to skin surface using double-sided and medical tapes.
  • Surface electromyographic signals from up to 14 muscles on the paretic and non-paretic side during gait.
    • Time Frame: The assessment will be performed at 5.5 weeks
    • To assess the muscle synergies, surface EMGs will be recorded from 14 muscles (tibialis anterior (TA), medical gastrocnemius (MG), soleus (SOL), vastus medialis (VM), rectus femoris (RF), hamstrings (HAM), adductor longus (AL), gluteus maximus (GM) lateral gastrocnemius (LG), vastus lateralis (VL), tensor fasciae latae (TFL), erector spinae (ES), external oblique (EO), and latissimus dorsi (LatDor)), using a wireless EMG system (Delsys; 2000 Hz). All electrodes will be securely attached to skin surface using double-sided and medical tapes.
  • Surface electromyographic signals from up to 14 muscles on the paretic and non-paretic side during gait.
    • Time Frame: The assessment will be performed at 2.5 weeks
    • To assess the muscle synergies, surface EMGs will be recorded from 14 muscles (tibialis anterior (TA), medical gastrocnemius (MG), soleus (SOL), vastus medialis (VM), rectus femoris (RF), hamstrings (HAM), adductor longus (AL), gluteus maximus (GM) lateral gastrocnemius (LG), vastus lateralis (VL), tensor fasciae latae (TFL), erector spinae (ES), external oblique (EO), and latissimus dorsi (LatDor)), using a wireless EMG system (Delsys; 2000 Hz). All electrodes will be securely attached to skin surface using double-sided and medical tapes.

Secondary Measures

  • Gait kinemetics
    • Time Frame: The assessment will be performed at baseline
    • During FES sessions, kinematic measurements will be provided by the wearable’s IMUs. During sessions of motor-impairment assessments, we will capture more precise kinematics using a 10-camera motion capture system (VICON; 200 Hz). This system tracks the 3D positions of 40 markers placed on the legs and torso, and is equipped with suitable models for reconstructing bilateral angles of the hip, knee and ankle.
  • Gait kinemetics
    • Time Frame: The assessment will be performed at 5.5 weeks
    • During FES sessions, kinematic measurements will be provided by the wearable’s IMUs. During sessions of motor-impairment assessments, we will capture more precise kinematics using a 10-camera motion capture system (VICON; 200 Hz). This system tracks the 3D positions of 40 markers placed on the legs and torso, and is equipped with suitable models for reconstructing bilateral angles of the hip, knee and ankle.
  • Gait kinemetics
    • Time Frame: The assessment will be performed at 2.5 weeks
    • During FES sessions, kinematic measurements will be provided by the wearable’s IMUs. During sessions of motor-impairment assessments, we will capture more precise kinematics using a 10-camera motion capture system (VICON; 200 Hz). This system tracks the 3D positions of 40 markers placed on the legs and torso, and is equipped with suitable models for reconstructing bilateral angles of the hip, knee and ankle.
  • Gait kinemetics
    • Time Frame: The assessment will be performed at 4 weeks
    • During FES sessions, kinematic measurements will be provided by the wearable’s IMUs. During sessions of motor-impairment assessments, we will capture more precise kinematics using a 10-camera motion capture system (VICON; 200 Hz). This system tracks the 3D positions of 40 markers placed on the legs and torso, and is equipped with suitable models for reconstructing bilateral angles of the hip, knee and ankle.
  • Fugl-Meyer assessment score (lower-limb)
    • Time Frame: The assessment will be performed at baseline
    • Lower-limb motor function assessment
  • Fugl-Meyer assessment score (lower-limb)
    • Time Frame: The assessment will be performed at 5.5 weeks
    • Lower-limb motor function assessment
  • Fugl-Meyer assessment score (lower-limb)
    • Time Frame: The assessment will be performed at 2.5 weeks
    • Lower-limb motor function assessment
  • Fugl-Meyer assessment score (lower-limb)
    • Time Frame: The assessment will be performed at 4 weeks
    • Lower-limb motor function assessment
  • Mini-BEStest
    • Time Frame: The assessment will be performed at baseline
    • Balance test
  • Mini-BEStest
    • Time Frame: The assessment will be performed at 5.5 weeks
    • Balance test
  • Mini-BEStest
    • Time Frame: The assessment will be performed at 2.5 weeks
    • Balance test
  • Mini-BEStest
    • Time Frame: The assessment will be performed at 4 weeks
    • Balance test

Participating in This Clinical Trial

Inclusion Criteria

1. Right-handed elderly chronic stroke survivors; age ≥40; ≥6 months post-stroke 2. Unilateral ischemic brain lesions 3. Participants should be able to walk continuously for ≥15 min. with or without assistive aid Exclusion Criteria:

1. Cannot comprehend and follow instructions, or with a score <21 on the mini-mental state exam; 2. Have cardiac pacemaker; 3. Have skin lesions at the locations where FES or EMG electrodes may be attached; 4. Have major depression; 5. Present with severe neglect 6. Patients with type i and ii diabetes

Gender Eligibility: All

Minimum Age: 40 Years

Maximum Age: 85 Years

Are Healthy Volunteers Accepted: No

Investigator Details

  • Lead Sponsor
    • Chinese University of Hong Kong
  • Collaborator
    • The Hong Kong Polytechnic University
  • Provider of Information About this Clinical Study
    • Principal Investigator: Cheung Chi Kwan Vincent, Assistant Professor – Chinese University of Hong Kong
  • Overall Contact(s)
    • Vincent Chi Kwan Cheung, PhD, +852 3943 9389, vckc@cuhk.edu.hk

References

Perry J, Garrett M, Gronley JK, Mulroy SJ. Classification of walking handicap in the stroke population. Stroke. 1995 Jun;26(6):982-9. doi: 10.1161/01.str.26.6.982.

Krasovsky T, Levin MF. Review: toward a better understanding of coordination in healthy and poststroke gait. Neurorehabil Neural Repair. 2010 Mar-Apr;24(3):213-24. doi: 10.1177/1545968309348509. Epub 2009 Oct 12.

Kollen BJ, Lennon S, Lyons B, Wheatley-Smith L, Scheper M, Buurke JH, Halfens J, Geurts AC, Kwakkel G. The effectiveness of the Bobath concept in stroke rehabilitation: what is the evidence? Stroke. 2009 Apr;40(4):e89-97. doi: 10.1161/STROKEAHA.108.533828. Epub 2009 Jan 29.

Cho JE, Yoo JS, Kim KE, Cho ST, Jang WS, Cho KH, Lee WH. Systematic Review of Appropriate Robotic Intervention for Gait Function in Subacute Stroke Patients. Biomed Res Int. 2018 Feb 6;2018:4085298. doi: 10.1155/2018/4085298. eCollection 2018.

Peckham PH, Knutson JS. Functional electrical stimulation for neuromuscular applications. Annu Rev Biomed Eng. 2005;7:327-60. doi: 10.1146/annurev.bioeng.6.040803.140103.

Sheffler LR, Chae J. Neuromuscular electrical stimulation in neurorehabilitation. Muscle Nerve. 2007 May;35(5):562-90. doi: 10.1002/mus.20758.

LIBERSON WT, HOLMQUEST HJ, SCOT D, DOW M. Functional electrotherapy: stimulation of the peroneal nerve synchronized with the swing phase of the gait of hemiplegic patients. Arch Phys Med Rehabil. 1961 Feb;42:101-5. No abstract available.

Heller BW, Clarke AJ, Good TR, Healey TJ, Nair S, Pratt EJ, Reeves ML, van der Meulen JM, Barker AT. Automated setup of functional electrical stimulation for drop foot using a novel 64 channel prototype stimulator and electrode array: results from a gait-lab based study. Med Eng Phys. 2013 Jan;35(1):74-81. doi: 10.1016/j.medengphy.2012.03.012. Epub 2012 May 4.

Springer S, Vatine JJ, Wolf A, Laufer Y. The effects of dual-channel functional electrical stimulation on stance phase sagittal kinematics in patients with hemiparesis. J Electromyogr Kinesiol. 2013 Apr;23(2):476-82. doi: 10.1016/j.jelekin.2012.10.017. Epub 2012 Dec 8.

You G, Liang H, Yan T. Functional electrical stimulation early after stroke improves lower limb motor function and ability in activities of daily living. NeuroRehabilitation. 2014;35(3):381-9. doi: 10.3233/NRE-141129.

Daly JJ, Roenigk K, Holcomb J, Rogers JM, Butler K, Gansen J, McCabe J, Fredrickson E, Marsolais EB, Ruff RL. A randomized controlled trial of functional neuromuscular stimulation in chronic stroke subjects. Stroke. 2006 Jan;37(1):172-8. doi: 10.1161/01.STR.0000195129.95220.77. Epub 2005 Dec 1.

Alon G. Use of neuromuscular electrical stimulation in neureorehabilitation: a challenge to all. J Rehabil Res Dev. 2003 Nov-Dec;40(6):ix-xii. doi: 10.1682/jrrd.2003.11.0009. No abstract available.

Alon G, Levitt AF, McCarthy PA. Functional electrical stimulation enhancement of upper extremity functional recovery during stroke rehabilitation: a pilot study. Neurorehabil Neural Repair. 2007 May-Jun;21(3):207-15. doi: 10.1177/1545968306297871. Epub 2007 Mar 16.

Cauraugh JH, Kim SB. Chronic stroke motor recovery: duration of active neuromuscular stimulation. J Neurol Sci. 2003 Nov 15;215(1-2):13-9. doi: 10.1016/s0022-510x(03)00169-2.

Saltiel P, Wyler-Duda K, D'Avella A, Tresch MC, Bizzi E. Muscle synergies encoded within the spinal cord: evidence from focal intraspinal NMDA iontophoresis in the frog. J Neurophysiol. 2001 Feb;85(2):605-19. doi: 10.1152/jn.2001.85.2.605.

Ivanenko YP, Poppele RE, Lacquaniti F. Five basic muscle activation patterns account for muscle activity during human locomotion. J Physiol. 2004 Apr 1;556(Pt 1):267-82. doi: 10.1113/jphysiol.2003.057174. Epub 2004 Jan 14.

d'Avella A, Saltiel P, Bizzi E. Combinations of muscle synergies in the construction of a natural motor behavior. Nat Neurosci. 2003 Mar;6(3):300-8. doi: 10.1038/nn1010.

Bernstein N (1967) The co-ordination and regulation of movements. Oxf. PergamoPress.

Ting LH, Chiel HJ, Trumbower RD, Allen JL, McKay JL, Hackney ME, Kesar TM. Neuromechanical principles underlying movement modularity and their implications for rehabilitation. Neuron. 2015 Apr 8;86(1):38-54. doi: 10.1016/j.neuron.2015.02.042.

McMorland AJ, Runnalls KD, Byblow WD. A neuroanatomical framework for upper limb synergies after stroke. Front Hum Neurosci. 2015 Feb 16;9:82. doi: 10.3389/fnhum.2015.00082. eCollection 2015.

Tresch MC, Cheung VC, d'Avella A. Matrix factorization algorithms for the identification of muscle synergies: evaluation on simulated and experimental data sets. J Neurophysiol. 2006 Apr;95(4):2199-212. doi: 10.1152/jn.00222.2005. Epub 2006 Jan 4.

Brunnström S (1970) Movement therapy in hemiplegia: a neurophysiological approach. Medical Dept., Harper & Row.

Saltiel P, Wyler-Duda K, d'Avella A, Ajemian RJ, Bizzi E. Localization and connectivity in spinal interneuronal networks: the adduction-caudal extension-flexion rhythm in the frog. J Neurophysiol. 2005 Sep;94(3):2120-38. doi: 10.1152/jn.00117.2005. Epub 2005 May 31.

Saltiel P, d'Avella A, Wyler-Duda K, Bizzi E. Synergy temporal sequences and topography in the spinal cord: evidence for a traveling wave in frog locomotion. Brain Struct Funct. 2016 Nov;221(8):3869-3890. doi: 10.1007/s00429-015-1133-5. Epub 2015 Oct 26.

Levine AJ, Hinckley CA, Hilde KL, Driscoll SP, Poon TH, Montgomery JM, Pfaff SL. Identification of a cellular node for motor control pathways. Nat Neurosci. 2014 Apr;17(4):586-93. doi: 10.1038/nn.3675. Epub 2014 Mar 9.

Cheung VC, d'Avella A, Bizzi E. Adjustments of motor pattern for load compensation via modulated activations of muscle synergies during natural behaviors. J Neurophysiol. 2009 Mar;101(3):1235-57. doi: 10.1152/jn.01387.2007. Epub 2008 Dec 17.

Cheung VC, d'Avella A, Tresch MC, Bizzi E. Central and sensory contributions to the activation and organization of muscle synergies during natural motor behaviors. J Neurosci. 2005 Jul 6;25(27):6419-34. doi: 10.1523/JNEUROSCI.4904-04.2005.

Caggiano V, Cheung VC, Bizzi E. An Optogenetic Demonstration of Motor Modularity in the Mammalian Spinal Cord. Sci Rep. 2016 Oct 13;6:35185. doi: 10.1038/srep35185.

Bizzi E, Mussa-Ivaldi FA, Giszter S. Computations underlying the execution of movement: a biological perspective. Science. 1991 Jul 19;253(5017):287-91. doi: 10.1126/science.1857964.

Takei T, Confais J, Tomatsu S, Oya T, Seki K. Neural basis for hand muscle synergies in the primate spinal cord. Proc Natl Acad Sci U S A. 2017 Aug 8;114(32):8643-8648. doi: 10.1073/pnas.1704328114. Epub 2017 Jul 24.

Zhuang C, Marquez J, Qu H, He X, Lan N (2015) A neuromuscular electrical stimulation strategy based on muscle synergy for stroke rehabilitation. 2015:816-819.

He X, Du YF, Lan N. Evaluation of feedforward and feedback contributions to hand stiffness and variability in multijoint arm control. IEEE Trans Neural Syst Rehabil Eng. 2013 Jul;21(4):634-47. doi: 10.1109/TNSRE.2012.2234479. Epub 2012 Dec 20.

Niu C, Zhuang C, Bao Y, Li S, Lan N, Xie Q (2017)

Niu C (2018) Effectiveness of Short-Term Training with a Synergy-Based FES Paradigm on Motor Function Recovery Post Stroke, in 12th International Society of Physical and Rehabilitation Medicine World Congress (Paris, France).

Ferrante S, Chia Bejarano N, Ambrosini E, Nardone A, Turcato AM, Monticone M, Ferrigno G, Pedrocchi A. A Personalized Multi-Channel FES Controller Based on Muscle Synergies to Support Gait Rehabilitation after Stroke. Front Neurosci. 2016 Sep 16;10:425. doi: 10.3389/fnins.2016.00425. eCollection 2016.

Barreca S, Wolf SL, Fasoli S, Bohannon R. Treatment interventions for the paretic upper limb of stroke survivors: a critical review. Neurorehabil Neural Repair. 2003 Dec;17(4):220-6. doi: 10.1177/0888439003259415.

Bernhardt J, Borschmann K, Boyd L, Carmichael ST, Corbett D, Cramer SC, Hoffmann T, Kwakkel G, Savitz S, Saposnik G, Walker M, Ward N. Moving Rehabilitation Research Forward: Developing Consensus Statements for Rehabilitation and Recovery Research. Neurorehabil Neural Repair. 2017 Aug;31(8):694-698. doi: 10.1177/1545968317724290.

Fugl-Meyer AR, Jaasko L, Leyman I, Olsson S, Steglind S. The post-stroke hemiplegic patient. 1. a method for evaluation of physical performance. Scand J Rehabil Med. 1975;7(1):13-31.

Dipietro L, Krebs HI, Fasoli SE, Volpe BT, Stein J, Bever C, Hogan N. Changing motor synergies in chronic stroke. J Neurophysiol. 2007 Aug;98(2):757-68. doi: 10.1152/jn.01295.2006. Epub 2007 Jun 6.

Bowden MG, Clark DJ, Kautz SA. Evaluation of abnormal synergy patterns poststroke: relationship of the Fugl-Meyer Assessment to hemiparetic locomotion. Neurorehabil Neural Repair. 2010 May;24(4):328-37. doi: 10.1177/1545968309343215. Epub 2009 Sep 30.

Gladstone DJ, Danells CJ, Black SE. The fugl-meyer assessment of motor recovery after stroke: a critical review of its measurement properties. Neurorehabil Neural Repair. 2002 Sep;16(3):232-40. doi: 10.1177/154596802401105171.

Levin MF, Kleim JA, Wolf SL. What do motor "recovery" and "compensation" mean in patients following stroke? Neurorehabil Neural Repair. 2009 May;23(4):313-9. doi: 10.1177/1545968308328727. Epub 2008 Dec 31.

Safavynia SA, Torres-Oviedo G, Ting LH. Muscle Synergies: Implications for Clinical Evaluation and Rehabilitation of Movement. Top Spinal Cord Inj Rehabil. 2011 Summer;17(1):16-24. doi: 10.1310/sci1701-16.

Stinear CM, Barber PA, Smale PR, Coxon JP, Fleming MK, Byblow WD. Functional potential in chronic stroke patients depends on corticospinal tract integrity. Brain. 2007 Jan;130(Pt 1):170-80. doi: 10.1093/brain/awl333.

Kim B, Winstein C. Can Neurological Biomarkers of Brain Impairment Be Used to Predict Poststroke Motor Recovery? A Systematic Review. Neurorehabil Neural Repair. 2017 Jan;31(1):3-24. doi: 10.1177/1545968316662708. Epub 2016 Aug 8.

Cheung VC, Piron L, Agostini M, Silvoni S, Turolla A, Bizzi E. Stability of muscle synergies for voluntary actions after cortical stroke in humans. Proc Natl Acad Sci U S A. 2009 Nov 17;106(46):19563-8. doi: 10.1073/pnas.0910114106. Epub 2009 Oct 30.

Roh J, Rymer WZ, Perreault EJ, Yoo SB, Beer RF. Alterations in upper limb muscle synergy structure in chronic stroke survivors. J Neurophysiol. 2013 Feb;109(3):768-81. doi: 10.1152/jn.00670.2012. Epub 2012 Nov 14.

Li S, Zhuang C, Niu CM, Bao Y, Xie Q, Lan N. Evaluation of Functional Correlation of Task-Specific Muscle Synergies with Motor Performance in Patients Poststroke. Front Neurol. 2017 Jul 19;8:337. doi: 10.3389/fneur.2017.00337. eCollection 2017.

Clark DJ, Ting LH, Zajac FE, Neptune RR, Kautz SA. Merging of healthy motor modules predicts reduced locomotor performance and muscle coordination complexity post-stroke. J Neurophysiol. 2010 Feb;103(2):844-57. doi: 10.1152/jn.00825.2009. Epub 2009 Dec 9.

Barroso FO, Torricelli D, Molina-Rueda F, Alguacil-Diego IM, Cano-de-la-Cuerda R, Santos C, Moreno JC, Miangolarra-Page JC, Pons JL. Combining muscle synergies and biomechanical analysis to assess gait in stroke patients. J Biomech. 2017 Oct 3;63:98-103. doi: 10.1016/j.jbiomech.2017.08.006. Epub 2017 Aug 20.

Routson RL, Clark DJ, Bowden MG, Kautz SA, Neptune RR. The influence of locomotor rehabilitation on module quality and post-stroke hemiparetic walking performance. Gait Posture. 2013 Jul;38(3):511-7. doi: 10.1016/j.gaitpost.2013.01.020. Epub 2013 Mar 13.

Hashiguchi Y, Ohata K, Kitatani R, Yamakami N, Sakuma K, Osako S, Aga Y, Watanabe A, Yamada S. Merging and Fractionation of Muscle Synergy Indicate the Recovery Process in Patients with Hemiplegia: The First Study of Patients after Subacute Stroke. Neural Plast. 2016;2016:5282957. doi: 10.1155/2016/5282957. Epub 2016 Dec 19.

Lee DD, Seung HS. Learning the parts of objects by non-negative matrix factorization. Nature. 1999 Oct 21;401(6755):788-91. doi: 10.1038/44565.

Cerina L, Cancian P, Franco G, Santambrogio M (2017) A hardware acceleration for surface EMG non-negative matrix factorization. IEEE Int Parallel & Distributed Processing Symposium Workshops 2017: 168-74.

Santuz A, Ekizos A, Janshen L, Baltzopoulos V, Arampatzis A. On the Methodological Implications of Extracting Muscle Synergies from Human Locomotion. Int J Neural Syst. 2017 Aug;27(5):1750007. doi: 10.1142/S0129065717500071. Epub 2016 Sep 23.

Devarajan K, Cheung VC. On nonnegative matrix factorization algorithms for signal-dependent noise with application to electromyography data. Neural Comput. 2014 Jun;26(6):1128-68. doi: 10.1162/NECO_a_00576. Epub 2014 Mar 31.

Ivanenko YP, Poppele RE, Lacquaniti F. Spinal cord maps of spatiotemporal alpha-motoneuron activation in humans walking at different speeds. J Neurophysiol. 2006 Feb;95(2):602-18. doi: 10.1152/jn.00767.2005. Epub 2005 Nov 9.

Bohannon RW. Comfortable and maximum walking speed of adults aged 20-79 years: reference values and determinants. Age Ageing. 1997 Jan;26(1):15-9. doi: 10.1093/ageing/26.1.15.

Cheung VC, Turolla A, Agostini M, Silvoni S, Bennis C, Kasi P, Paganoni S, Bonato P, Bizzi E. Muscle synergy patterns as physiological markers of motor cortical damage. Proc Natl Acad Sci U S A. 2012 Sep 4;109(36):14652-6. doi: 10.1073/pnas.1212056109. Epub 2012 Aug 20.

Dominici N, Ivanenko YP, Cappellini G, d'Avella A, Mondi V, Cicchese M, Fabiano A, Silei T, Di Paolo A, Giannini C, Poppele RE, Lacquaniti F. Locomotor primitives in newborn babies and their development. Science. 2011 Nov 18;334(6058):997-9. doi: 10.1126/science.1210617.

Bizzi E, Cheung VC. The neural origin of muscle synergies. Front Comput Neurosci. 2013 Apr 29;7:51. doi: 10.3389/fncom.2013.00051. eCollection 2013.

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