ESTIM-UL: FES for Upper Limb Recovery After Stroke

Inclusion Criteria: * Age 18 years or older. * Diagnosis of ischemic or hemorrhagic stroke, documented by CT or MRI. * Clinical presence of focal upper limb spasticity, defined as a score ≥ 1+ on the Modified Ashworth Scale (MAS) in at least one target muscle group (elbow, wrist, or finger flexors), treated with Botulinum Toxin Type A injection. * Presence of residual voluntary muscle activation (minimal active movement) sufficient to initiate the motor task required by the training (Box and Block score ≥ 1). * Preserved cognitive function, defined as a Mini-Mental State Examination (MMSE) score ≥ 24 or clinical judgment confirming adequate comprehension and cooperation. Exclusion Criteria: * Absolute contraindications to Functional Electrical Stimulation (FES), including the presence of a cardiac pacemaker or implantable cardioverter defibrillator (ICD), pharmacologically uncontrolled epilepsy, or skin lesions/dermatitis at the electrode application sites. * Presence of severe muscle-tendon contractures or fixed joint deformities (ankylosis) that mechanically limit passive movement and make active functional recovery unlikely. * Severe cognitive impairment, global aphasia, or severe unilateral spatial neglect that prevents task comprehension or active participation in the training program. * Concomitant orthopedic or rheumatologic conditions affecting the upper limb (e.g., recent fractures, severe arthritis) that could interfere with treatment delivery or outcome assessment.