Effect of TENS on Spasticity

The purpose of this clinical trial is to evaluate whether Transcutaneous Electrical Nerve Stimulation (TENS) is effective in reducing spasticity in adults with post-stroke spasticity. The primary research question is whether TENS can reduce the severity of spasticity. The effectiveness of TENS will be assessed by comparing spasticity-related outcomes measured before, during, and after the intervention. Participants will first undergo a one-hour baseline monitoring period, during which assessments will be conducted at 10-minute intervals. This will be followed by a 30-minute TENS intervention and a two-hour follow-up period, with assessments performed every 10 minutes. One participant will repeat this protocol once daily for three consecutive days, whereas the remaining three participants will undergo the procedure on a single occasion.

Inclusion Criteria: * Age between 18 and 70 years * Post-stroke wrist flexor spasticity scored as Grade 2 or 3 on the Australian Spasticity Assessment Scale (ASAS), specifically selecting patients whose passive stretch resistance (post-catch response) can be easily overcome to ensure accurate and unconfounded electrophysiological evaluation. * At least 6 months post-stroke (chronic phase). * Provision of voluntary, written informed consent prior to study enrollment. Exclusion Criteria: * Age \70 year * Contraindications to transcutaneous electrical nerve stimulation (e.g., implanted electronic devices, history of epilepsy, or localized skin lesions preventing electrode placement) * Concomitant wrist contracture or pain sufficient to impede clinical evaluation * Structural abnormalities of the elbow joint obstructing median nerve stimulation * Median nerve neuropathy or injury in the affected upper extremity. * Non-stable dosage of antispastic medications within the 2 weeks prior to baseline * Initiation of medications affecting nerve conduction (e.g., antidepressants, anticonvulsants, anesthetics) within the past month; patients on a stable dose for \>1 month remain eligible * Botulinum toxin injection in the target spastic muscles within the preceding 3 months * History of neurolytic procedures targeting spasticity in the affected limb. * History of orthopedic or neurological surgery targeting spasticity in the affected limb * Cognitive impairment severe enough to compromise adherence to study protocols * Inability to maintain the required testing positions for the upper extremity joints (shoulder, elbow, forearm, and wrist) * Pregnancy or breastfeeding * Presence of active malignancy at or near the treatment area.