Effects of a Robot-based Sensorimotor Upper Limb Rehabilitation Paradigm in Chronic Stroke: a Randomized Controlled Trial

Sensorimotor function of the upper limb is commonly impaired after stroke, even in the chronic phase (\>6 months post-stroke). Nevertheless, good sensorimotor function is needed for daily life functioning. Sensorimotor function can be divided into three components: exteroception, proprioception and sensory processing. It is important that those three components will each be addressed in the upper limb rehabilitation. Unfortunately, there is still no optimal therapy to address sensory processing. Therefore, we developed an intensive sensorimotor robot-based rehabilitation paradigm (called ROBUST) with focus on sensory processing. As a first step, we did a pilot study (S69003) including 10 persons with chronic stroke to investigate the potential effectiveness and feasibility of this novel rehabilitation. The median change score of motor, sensory and sensorimotor assessments was exceeding the minimal clinical important difference (MCID), and the total amount of therapy was feasible as well. The investigated protocols to measure potential changes in brain function (activity and connectivity) and structure accompanying the novel therapy appeared feasible as well. Based on this first pilot study, we finalized the protocol for this RCT to investigate the effectiveness of the ROBUST intervention.

Sensorimotor function of the upper limb is commonly impaired after stroke, even in the chronic phase (\>6 months post-stroke). Nevertheless, good sensorimotor function is needed for daily life functioning. Sensorimotor function can be divided into three components: exteroception, proprioception and sensory processing. It is important that those three components will each be addressed in the upper limb rehabilitation. Unfortunately, there is still no optimal therapy to address sensory processing. Therefore, we developed an intensive sensorimotor robot-based rehabilitation paradigm (called ROBUST) with focus on sensory processing. As a first step, we did a pilot study (S69003) including 10 persons with chronic stroke to investigate the potential effectiveness and feasibility of this novel rehabilitation. The median change score of motor, sensory and sensorimotor assessments was exceeding the minimal clinical important difference (MCID), and the total amount of therapy was feasible as well. The investigated protocols to measure potential changes in brain function (activity and connectivity) and structure accompanying the novel therapy appeared feasible as well. Based on this first pilot study, we finalized the protocol for this RCT. Within this RCT, we will include participants with chronic stroke and healthy controls. The participants with stroke will be randomly divided in two groups: the experimental group and control group. The experimental group will receive an additional integrated treatment paradigm to their standard care. This novel integrated treatment (called ROBUST) is a combination of robot-based (Kinarm), conventional and home therapy. The control group will first receive their standard care alone, followed by an additional Kinarm therapy (one part of ROBUST) to their standard care. The healthy controls will also first receive no additional therapy, followed by the additional Kinarm therapy. After each control period (no extra therapy) and/or each intervention period (additional ROBUST or Kinarm therapy), a follow-up period is included whereby the participants just follow their standard care. The aim is to investigate the effects of the additional ROBUST rehabilitation, compared to the standard care, and compared to the additional Kinarm therapy. We will investigate the differences in sensorimotor improvement induced by the additional Kinarm therapy between persons with stroke and healthy controls. Finally, we will investigate the clinical and kinematic effectiveness, as well as potential changes in brain function (activity and connectivity) and structure.

Inclusion Criteria stroke participants: 1. Written informed consent must be obtained prior to any screening procedures; 2. A first-ever unilateral, supra-tentorial stroke, as defined by WHO (rapidly developing clinical signs of focal (or global) disturbance of cerebral function, with symptoms lasting 24 hours or longer or leading to death, with no apparent cause other than vascular origin); 3. ≥18 and ≤85 years old; 4. Being a Dutch speaker; 5. Being in the chronic phase after stroke, i.e. \> 6 months post stroke; 6. Motor impairment in the upper limb, defined as Fugl-Meyer score \>22 out of 66 to demonstrate moderate to full upper limb motor function (patients scoring \<23 out of 66 will not be able to comply with the Kinarm protocol); 7. Residual sensory upper limb impairment, defined as Tactile Discrimination Test (Area Under Curve) \<73.10%; 8. Impaired functionality, defined as sensorimotor Action Research Arm Test score \<52 out of 57; 9. Manageable spasticity for Kinarm tasks. Inclusion Criteria healthy participants: 1. Written informed consent must be obtained prior to any screening procedures; 2. ≥18 and ≤85 years old; 3. Being a Dutch or English speaker; 4. No history of stroke or transient ischemic attack; 5. No recent brain/head injury; 6. No major upper limb sensory or motor impairments. Exclusion Criteria: 1. Having musculoskeletal and/or other neurological disorders impacting care or prognosis; 2. Having severe communication or cognitive deficits that interfere with the protocol; 3. Having severe spasticity (cannot handle Kinarm robot); 4. Any disorder, which in the investigator's opinion might jeopardise participant's safety or compliance with the CIP; 5. Contraindications for robot-based therapy (e.g., uncontrolled epilepsy); 6. Participation in another clinical investigation; 7. Having any contraindications for fNIRS\*： * Uncontrolled head movements (e.g. tremor) * Scalp lesion at optode sites (wound/incision/infection/hematoma) * Decompressive craniectomy or large skull defect over target regions * Persistent hair-optode coupling failure despite best practices, or non-removable obstructions preventing adequate coupling 8. Having any contraindications for MRI\*\*: * Pacemaker * Implantable Cardioverter Defibrillator (ICD) * Cochlear implant * Internal Insulin-pump * Deep brain stimulation * Any other metal device in the body * Claustrophobia * Having a history of a neuropsychiatric or neurologic disorder before the diagnosis of stroke (e.g., depression, traumatic brain injury) * Use of psychoactive medication before the diagnosis of stroke (e.g., anti-depressive medication) * Misuse (or history of misuse) of drugs/alcohol 9. Currently undergoing a structured arm and/or hand training (e.g. engaging in playing a musical instrument)\*\*. * Stroke patients and healthy participants showing these exclusion criteria will be included in the RCT protocol, but will not be measured with fNIRS. * Stroke patients showing these exclusion criteria will be included in the RCT protocol, but will not be measured with MRI. Healthy adults showing these exclusion criteria will not be included in the study.