Improving Grasp Function in People With Sensorimotor Impairments by Combining Electrical Stimulation With a Robotic Hand Orthosis (SENSIBLE-EXO)

Hand motor and sensory impairments resulting from neurological disorders or injuries affect more than 50 million individuals worldwide. Conditions such as stroke, spinal cord injury (SCI), and traumatic brain injury (TBI) can cause long-term hand impairments, greatly impacting daily activities and social integration. Since traditional physiotherapy has limited effectiveness in rehabilitation, assistive devices helping in performing in daily activities have emerged as a necessary solution. Soft exoskeletons offer advantages as they are more comfortable and adaptable for the user, but they often struggle to generate sufficient force. On the other hand, electrical stimulation garments, like e-sleeves, show promise by stimulating nerves and muscles in the forearm. However, achieving precise and stable movement control remains challenging due to difficulties in electrode placement for targeted stimulation. Furthermore, none of the currently available devices are capable of artificially restoring lost sensation in users' hands, limiting their ability to manipulate with fragile objects.

Recognizing these limitations, our study proposes a solution that combines a standard hand soft exoskeleton with: (i) electrical stimulation to the fingers' flexor and extensor muscles to generate artificial muscle contractions synchronized with the exoskeleton motion, compensating for the lack of gripping force, and (ii) electrical stimulation to the nerves to artificially restore the lost sensation of touch, enabling users to receive feedback on the force they are applying when interacting with the environment. The investigators refer to this proposed combination as Sensible-Exo.

To achieve this goal, our project aims to evaluate the functional improvements in assistive and rehabilitative scenarios using SensoExo in comparison to use only the exoskeleton or having no support at all. The exoskeleton will be coupled with an electrical stimulating sleeve capable of delivering non-invasive electrical stimulation in the form of Functional Electrical Stimulation (FES) and Transcutaneous Electrical Nerve Stimulation (TENS). A glove with embedded force and bending sensors will be used to modulate the electrical stimulation. Additionally, apart from studying the enhancement of functional tasks, the investigators will explore improvements in body perception, representation, and multi-sensory integration. Indeed, the investigators also aim at identifying the way patients perceive their body by means of ad-hoc virtual reality assessments that has been developed. Before each assessment patient will perform some predefined movement in virtual reality to familiarize with it and increase embodiment.

During the study, participants will perform a range of tasks based on their residual abilities, including motor tasks (e.g., grab and release, Toronto Rehabilitation Institute Hand Function Test, grip force regulation test, virtual egg test), cognitive tasks (dual tasks), and assessments of body representation and perception. Some of these tasks will be conducted in Virtual Reality environments, both with and without active stimulation.

Study Overview

• Status: Active, not recruiting
• Conditions: Stroke; Traumatic Brain Injury; Spinal Cord Injuries
• Intervention / Treatment: Device: SensoExo

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zurich
    • Zürich, Zurich, Switzerland, 8001
      • Neuroengineering Lab

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Impairment of the motor and sensory functions of the hand in chronic stage
• The subject should have good proximal arm function (i.e. good shoulder abduction and elevation)

Exclusion Criteria:

• Cognitive and communication deficits impairment
• Prior or current psychological diseases such as borderline, schizophrenia, Depression or Maniac Depression
• Major comprehension and memory deficits
• Pregnancy
• Epilepsy
• Pacemaker
• Cybersickness

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental group	Device: SensoExo; combination of sensory feedback and the use of soft exoskeleton

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Range of Motion with electrical stimulation and without no electrical stimulation	Range of motion will be measured and compared among conditions	up to one month before; thorugh study completition (average 1 month); up to one month after
Change in the area with tactile feedback in the hand with electrical stimulation and with no electrical stimulation	Semmes-Weinstein Monofilament Test will be used to assess the residual tactile feedback	up to one month before; thorugh study completition (average 1 month); up to one month after
Change in functional tasks performance with sensory feedback and without sensory feedback quantified by the number of successful grasp and release tasks	Number of successful transportation of objects over an obstacle	up to one month before; thorugh study completition (average 1 month); up to one month after
Change between functional tasks with sensory feedback and with no sensory feedback in number of virtual egg successful grasping	Number of successful transportations of fragile objects over an obstacle	up to one month before; thorugh study completition (average 1 month); up to one month after
Change between functional tasks with sensory feedback and with no sensory feedback in grasping force	Grasping forces will be assessed during functional performance of the subjects	up to one month before; thorugh study completition (average 1 month); up to one month after
Change between tasks with sensory feedback and with no sensory feedback in arm joints kinemtics	Joint kinematics measurements will be measured with motion capture systems during functional performance of the subjects	up to one month before; thorugh study completition (average 1 month); up to one month after

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in experienced physical, mental, and social effects	Neuro-QuL measurement system will be as assessment tool	up one week before first session and up one week after last session
Change in Proprioceptive drift between different conditions	To measure embodiment subjects will be asked after VR sessions to indicate where they feel their arm without looking at the limb in real world. This is a measure of embodiment.	up one week before first session and up one week after last session
Change in Telescoping measures between different conditions	To measure embodiment subjects will be asked after VR sessions to indicate how long they feel their arm without looking at the limb in real world. This is a measure of embodiment.	up one week before first session and up one week after last session
Change from baseline performance between tasks accomplished with sensory feedback and with no sensory feedback in Embodiment	Embodiment will be measured with questionnaires (from -3 to +3, +3 totally agrees; two questions are from 1 to 10 (to measure vividness, where 10 is max vividness) and from 1 to 100 (to measure prevalence, where 100 is max duration of the embodiment feeling))	up one week before first session and up one week after last session
Measures of self-body representation	This will be measured in virtual reality by means of ad-hoc Body Landmark test. This is a body representation measurements.	up one week before first session; thorugh study completition (average 1 month); up one week after last session
Measures of body-space representation	This will be measured in virtual reality by means of ad-hoc Hand Peri personal Space test. This is a body representation measurements.	up one week before first session; thorugh study completition (average 1 month); up one week after last session

Collaborators and Investigators

• Sponsor: Andrea Cimolato
• Investigators: Principal Investigator: Stanisa Raspopovic, PhD, ETH Zurich

Publications and helpful links

General Publications

• Kwakkel G, Kollen BJ, van der Grond J, Prevo AJ. Probability of regaining dexterity in the flaccid upper limb: impact of severity of paresis and time since onset in acute stroke. Stroke. 2003 Sep;34(9):2181-6. doi: 10.1161/01.STR.0000087172.16305.CD. Epub 2003 Aug 7.
• Carey LM, Matyas TA, Oke LE. Sensory loss in stroke patients: effective training of tactile and proprioceptive discrimination. Arch Phys Med Rehabil. 1993 Jun;74(6):602-11. doi: 10.1016/0003-9993(93)90158-7.
• Fuhrer MJ, Rintala DH, Hart KA, Clearman R, Young ME. Relationship of life satisfaction to impairment, disability, and handicap among persons with spinal cord injury living in the community. Arch Phys Med Rehabil. 1992 Jun;73(6):552-7.
• Ciancibello J, King K, Meghrazi MA, Padmanaban S, Levy T, Ramdeo R, Straka M, Bouton C. Closed-loop neuromuscular electrical stimulation using feedforward-feedback control and textile electrodes to regulate grasp force in quadriplegia. Bioelectron Med. 2019 Nov 1;5:19. doi: 10.1186/s42234-019-0034-y. eCollection 2019.
• Wade DT. Measuring arm impairment and disability after stroke. Int Disabil Stud. 1989 Apr-Jun;11(2):89-92. doi: 10.3109/03790798909166398.
• Dannenbaum RM, Dykes RW. Sensory loss in the hand after sensory stroke: therapeutic rationale. Arch Phys Med Rehabil. 1988 Oct;69(10):833-9.
• Finnerup NB, Johannesen IL, Fuglsang-Frederiksen A, Bach FW, Jensen TS. Sensory function in spinal cord injury patients with and without central pain. Brain. 2003 Jan;126(Pt 1):57-70. doi: 10.1093/brain/awg007.
• Dannenbaum RM, Jones LA. The assessment and treatment of patients who have sensory loss following cortical lesions. J Hand Ther. 1993 Apr-Jun;6(2):130-8. doi: 10.1016/s0894-1130(12)80294-8.
• Noreau L, Fougeyrollas P. Long-term consequences of spinal cord injury on social participation: the occurrence of handicap situations. Disabil Rehabil. 2000 Mar 10;22(4):170-80. doi: 10.1080/096382800296863.
• Butzer T, Lambercy O, Arata J, Gassert R. Fully Wearable Actuated Soft Exoskeleton for Grasping Assistance in Everyday Activities. Soft Robot. 2021 Apr;8(2):128-143. doi: 10.1089/soro.2019.0135. Epub 2020 Jun 18.
• Beekhuizen KS. New perspectives on improving upper extremity function after spinal cord injury. J Neurol Phys Ther. 2005 Sep;29(3):157-62. doi: 10.1097/01.npt.0000282248.15911.38.
• Lambercy O, Dovat L, Yun H, Wee SK, Kuah CW, Chua KS, Gassert R, Milner TE, Teo CL, Burdet E. Effects of a robot-assisted training of grasp and pronation/supination in chronic stroke: a pilot study. J Neuroeng Rehabil. 2011 Nov 16;8:63. doi: 10.1186/1743-0003-8-63.
• Marquez-Chin C, Popovic MR. Functional electrical stimulation therapy for restoration of motor function after spinal cord injury and stroke: a review. Biomed Eng Online. 2020 May 24;19(1):34. doi: 10.1186/s12938-020-00773-4.
• Prochazka A, Gauthier M, Wieler M, Kenwell Z. The bionic glove: an electrical stimulator garment that provides controlled grasp and hand opening in quadriplegia. Arch Phys Med Rehabil. 1997 Jun;78(6):608-14. doi: 10.1016/s0003-9993(97)90426-3.
• Fujimoto ST, Longhi L, Saatman KE, Conte V, Stocchetti N, McIntosh TK. Motor and cognitive function evaluation following experimental traumatic brain injury. Neurosci Biobehav Rev. 2004 Jul;28(4):365-78. doi: 10.1016/j.neubiorev.2004.06.002.

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2023
• Primary Completion (Estimated): June 30, 2026
• Study Completion (Estimated): June 30, 2030

Study Registration Dates

• First Submitted: July 19, 2023
• First Submitted That Met QC Criteria: July 27, 2023
• First Posted (Actual): August 4, 2023

Study Record Updates

• Last Update Posted (Actual): August 19, 2025
• Last Update Submitted That Met QC Criteria: August 18, 2025
• Last Verified: August 1, 2025

More Information

Terms related to this study

• Keywords: TENS; exoskeleton; FES; sensorimotor; wearable robotics
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Craniocerebral Trauma; Trauma, Nervous System; Spinal Cord Diseases; Brain Injuries, Traumatic; Wounds and Injuries; Brain Injuries; Spinal Cord Injuries
• Other Study ID Numbers: 1-010428

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No