Effects of tVNS and mCIMT in Chronic Stroke

Summary

Stroke is a leading cause of death and disability worldwide, resulting in significant physical and cognitive impairments. Arm weakness is most common after stroke and its treatment is recognized as an area of considerable need. The functional limitations and disabilities experienced by stroke survivors, particularly in the upper limb have a profound impact on their quality of life. Current treatment for arm weakness typically comprises intensive, task-specific and repetitive rehabilitative interventions. Transcutaneous auricular vagus nerve stimulation (tVNS) is a novel noninvasive treatment for stroke that directly stimulates the peripheral auricular branch of the vagus nerve. This study determines the effects of Vagus Nerve Stimulation and Modified Constraint Induced Movement Therapy on Motor Function, Cognition, and Quality of life in chronic stroke patients.

This randomized clinical trial will be conducted at IIMCT Railway General Hospital and Al-firdous physiotherapy clinic over a duration of six months. The sample size will consist of 50 participants. Participants which meet the inclusion criteria will be taken through non-probability convenience sampling technique, which will further be randomized through online randomization tool. 25 Participants will be assigned to Group A receiving tVNS and mCIMT with routine physical therapy and 25 to Group B receiving mCIMT with routine physical therapy . Data will be collected using various assessment tools, including Fugl-Meyer Assessment-UE (FM-UE), and Nine-hole peg test (NHPT) to assess Motor function. Stroke Impact Scale (SIS) to assess QOL, Montreal cognitive assessment (MoCA) to assess cognition, and Modified Ashworth scale to assess spasticity. All participants will receive intervention 3 days a week on alternative days for 8 weeks. Pre-intervention assessments will be conducted for both groups. The effects of the interventions will be measured at pre-treatment, 4th week, and post-intervention. Data analysis will be performed by using SPSS 26 software.

Key words: Modified Constraint Induced movement Therapy, Motor function, Rehabilitation, Stroke, Transcutaneous Vagus nerve stimulation, Upper extremity.

Conditions

• Stroke
• Cerebrovascular Accident

Interventions

DEVICE

Transcutaneous Vagus Nerve Stimulation

Each treatment session will last one hour, conducted three times per week on alternate days for eight weeks. The session will begin with 30 minutes of routine physical therapy, which will include active and active-assisted range of motion exercises, strengthening and coordination activities, and functional task training for the upper extremity. The following 30 minutes will include concurrent tVNS and mCIMT. tVNS will be administered through surface electrodes placed on the auricular region (tragus or cymba conchae) of the ear, with stimulation parameters set at a frequency of 25 Hz, pulse width of 250 μs, and intensity adjusted to a comfortable tingling level below the pain threshold. During this period, participants will perform task-oriented activities of the affected upper limb through functional tasks such as reaching, grasping, and object manipulation. Shaping techniques will be used to progressively increase task difficulty, and a soft mitt applied to the unaffected hand.

OTHER

Modified Constraint Induced Movement Therapy with Routine Physical Therapy

Participants will also receive session lasting for one hour, with 30 minutes devoted to routine physical therapy followed by 30 minutes of mCIMT. The routine physical therapy component will include range of motion exercises, stretching, strengthening, and functional movement training similar to Group A to ensure treatment uniformity. The 30-minute mCIMT intervention will consist of intensive, task-specific practice of the affected upper limb under therapist supervision, focusing on goal-oriented functional tasks and repetitive training to enhance motor performance. A shaping approach will be used to progressively increase task complexity based on individual capability, and a soft constraint applied to the unaffected limb during the session.

Sponsors & Collaborators

• Riphah International University

  lead OTHER

Principal Investigators

• Aruba Saeed, Phd · Riphah International University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

50 Years

Max Age

75 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-11-25

Primary Completion

2026-05-05

Completion

2026-05-05

Countries

• Pakistan

Study Locations