This multicenter international randomized controlled trial (RCT) evaluates the effectiveness of the Gloreha Sinfonia® robotic exoskeleton for upper limb rehabilitation in individuals with subacute post-stroke paresis. The study aims to determine whether robotic-assisted therapy improves voluntary motor control and coordination more effectively than conventional rehabilitation, as measured by the Fugl-Meyer Assessment (FMA) for the upper limb (motor component).

Participants will be randomly assigned to one of two groups:

• Experimental Group (EG): Robotic-assisted upper limb rehabilitation combined with conventional therapy.
• Control Group (CG): Conventional therapy alone including upper limb rehabilitation.

Clinical assessments will be conducted at baseline (T1), post-treatment (T2), and at a 3-month follow-up (T3) using remotely administered scales.

Secondary objectives include evaluating improvements in muscle strength, range of motion, eye-hand coordination, manual dexterity, and functional independence. The study will also assess prognostic factors influencing response to robotic therapy, patient satisfaction, and potential adverse events.

Stroke is a leading cause of disability worldwide, with hemiparesis impairing upper limb function in 75% of affected patients. This deficit significantly reduces patients' independence in activities of daily living (ADLs) and limits social participation. Recovery of upper limb motor function is a primary goal in post-stroke rehabilitation. In recent years, robotic devices for hand rehabilitation have been introduced. The Gloreha Sinfonia® (R-Touch Pro, BTL Robotics) is a robotic exoskeleton that enables repetitive, intensive movements in passive, assisted, and active modes. Despite growing evidence supporting robotics in upper limb rehabilitation, significant gaps remain, including the lack of standardized protocols and the challenge of identifying patient subgroups that would benefit most. This multicenter international RCT aims to address these gaps by evaluating the short- and long-term effectiveness of robot-assisted therapy compared to conventional therapy. The primary objective is to measure the efficacy of robotic rehabilitation using the Fugl-Meyer Motor Assessment (0-66) for the upper limb, a validated scale assessing improvements in strength, active range of motion, eye-hand coordination, and dexterity. This outcome allows for a direct connection between robotic therapy results and motor function, ensuring a precise and replicable evaluation of treatment efficacy relative to conventional therapy. It is hypothesized that robotic treatment with Gloreha Sinfonia R-Touch Pro will significantly improve strength, active range of motion, eye-hand coordination, and manual dexterity, while also promoting autonomy in ADLs and social participation. The study also aims to identify clinical and prognostic factors that influence the response to robotic therapy, assess patient acceptance and satisfaction with the treatment, and monitor for any adverse events. Specifically, secondary objectives of the study are: to assess the impact of robotic treatment on muscle strength, active range of motion, hand-eye coordination, fine motor skills, and dexterity; to examine the effect of treatment on independence in daily living activities and social participation.

Identify clinical characteristics, such as severity of neurological impairment and time from acute event, that best respond to robot-assisted hand therapy; to investigate the influence of treatment initiation timing in relation to the acute event on rehabilitation effectiveness; to assess patient acceptance and satisfaction with the treatment, monitor the occurrence of adverse events, and analyze the effect of treatment on upper limb spasticity. Participants with a stroke diagnosis who meet the inclusion and exclusion criteria will be randomly assigned to one of the following groups: Experimental Group (EG) - robotic treatment for upper limb rehabilitation using the GS robotic device or Control Group (CG) - conventional treatment for upper limb rehabilitation. The study will span 36 months and includes two phases as follows: Phase 1 - Recruitment, baseline evaluations, randomization, rehabilitation intervention, final evaluations, and Phase 2 - Follow-up.

Eligible patients will be randomized into one of two treatment groups (Phase 1): EG or CG. All subjects will be evaluated (Phase 1) with a series of clinical assessments at baseline (T1) and the same assessments will be repeated at the end of the treatment (T2). A 3-month follow-up (Phase 2, T3) will be conducted either through an in-person clinical assessment or a phone interview, based on patient availability, using only remote-administered clinical scales. As for the rehabilitation treatments, the Experimental Group (EG) will receive upper limb rehabilitation assisted by the Gloreha Sinfonia R-Touch Pro device, in addition to conventional therapy, which includes physical therapy (PT) and occupational therapy (OT) and the Control Group (CG) will undergo the same upper limb rehabilitation with only conventional PT and OT treatments, matching the EG's duration for a total of 90 minutes. Both groups will engage in individualized rehabilitation programs, potentially incorporating additional personalized interventions based on each patient's clinical-neurological profile. Randomization will be conducted in a blind manner by an independent collaborator who is not involved in recruitment, intervention, or data collection. Sequentially numbered, opaque, and randomly ordered envelopes containing group assignments will be opened after the initial evaluation, in the participant's presence. Therapists involved will be informed of each patient's group assignment. All data will be collected in compliance with privacy regulations and anonymized on a dedicated platform called RedCAP (Research Electronic Data Capture) https://redcap.sanraffaele.it/. Each center will have access to its own data, with the ability to independently modify and update it. Data will be recorded through the Clinical Report Form (CRF), ensuring systematic and standardized data collection. Descriptive statistical analysis will be performed to adequately represent the clinical and demographic characteristics of the sample, with data presented as frequency (percentage), mean and standard deviation, and median (5th and 95th percentile) for categorical, continuous, and ordinal variables, respectively. Descriptive statistics will ensure score comparability between groups at baseline; an inferential analysis of variables (Kolmogorov-Smirnov test) will be conducted to verify the normality of data distributions. Parametric or non-parametric tests will be applied based on data distribution. The significance level will be set at p<0.05.

In conclusion, the main expected results are: to identify a standardized, reproducible rehabilitation protocol with robotic hand assistance to implement highly customizable rehabilitation protocols; to achieve improved motor recovery in terms of both range of motion and muscle recruitment following upper limb rehabilitation through the Gloreha Sinfonia® (R-Touch Pro) robotic system; to achieve better motor performance following upper limb rehabilitation through the Gloreha Sinfonia® robotic system; to obtain improved eye-hand coordination, manual dexterity, and fine motor skills; to attain greater autonomy in ADL and, consequently, greater participation; to identify any clinical and functional characteristics that impact the rehabilitation outcome with Gloreha Sinfonia R-Touch Pro.

Inclusion Criteria:

• Both sexes
• Age 18-90 years
• Paresis of the upper limb following a recent cerebrovascular event (subacute ischemic or hemorrhagic stroke)
• Moderate to mild muscle weakness in the thumb opponens, common finger flexors, and wrist flexors, assessed with complete joint movement in absence of gravity, Medical Research Council Scale (MRC) ≥ 2
• Time from acute event <90 days
• Ability to understand and sign the study informed consent
• Ability to perform study procedures.

Exclusion Criteria:

• Presence of other overlapping neurological disorders
• Presence of osteoarticular or neuromuscular disorders affecting upper limb mobility
• Severe psychiatric disorders
• Severe cognitive (MMSE ≤ 17) and/or language impairment compromising exercise comprehension
• Botulinum toxin injection in the affected upper limb within the last 60 days or planned during the study and follow-up period
• Open wounds, infections, or unprotected skin lesions on the upper limb
• Severe spasticity of the upper limb (biceps and wrist and finger flexors) (MAS > 3)
• Inability to adhere to the exercise program due to low compliance
• Participants who have not signed the informed consent for the study

Individual participant data (IPD) will be shared with qualified researchers upon reasonable request, following ethical and regulatory approvals.

Individual participant data (IPD) will be available upon publication of the main results and will remain accessible for at least five years.

Qualified researchers may request access to the data by submitting a proposal outlining their research objectives. Access will be granted upon ethical and regulatory approval and under a data-sharing agreement.

In this study all the outcome assessors will be blind to the gruop assignment of the study participants.