Effect of Combining Central and Peripheral Cutaneous Electrical Stimulation on Lower Limb Motor Function in People With Stroke

Official title

A Randomized Controlled Trial of Anodal Transcranial Direct Current Stimulation and Transcutaneous Electrical Nerve Stimulation for Improving Lower Limb Function in Stroke Patients

Overview

This study aims to evaluate the effectiveness of transcranial direct current stimulation (tDCS) and transcutaneous electrical nerve stimulation (TENS) in augmenting the efficacy of the lower limb task-oriented training in people with stroke. It is hypothesize that lower limb motor function can be best improved by combining anodal tDCS with TENS, when compared with sham-tDCS with TENS, anodal tDCS with placebo-TENS, or control training at improving ankle muscle strength, motor control of lower limbs, walking performance, functional mobility and community integration in people with stroke.

Detailed description

The application of transcutaneous electrical nerve stimulation (TENS) over a paretic lower limb could augment the effects of task-oriented exercise therapy on lower limb motor function in people with stroke, possibly through increased excitability of sensorimotor cortex.

In transcranial direct current stimulation (tDCS), a weak electrical current is applied through electrodes placed on the scalp to modulate cortical excitability and neural activity in targeted brain regions. Anodal tDCS, specifically, involves positioning the positively charged electrode over the targeted cortical area, which facilitates neuronal depolarization and increases cortical excitability in the underlying brain tissue. The enhanced neural excitability induced by anodal tDCS could promote neuroplasticity and optimize motor learning processes, potentially through the modulation of N-methyl-D-aspartic acid (NMDA) receptor -dependent mechanisms and alterations in GABAergic activity, leading to improved motor function and rehabilitation outcomes in various neurological conditions.

The next question concerns whether anodal tDCS could be combined with TENS and whether their synergetic effects could maximise the motor output of paretic limbs in people with stroke.

Interventions

• Device Transcranial direct current stimulation (tDCS)
  tDCS will be delivered by a constant-current electrical stimulator (DC-stimulator; Eldith, Ilmenau, Germany). Rectangular electrodes covered with a saline-soaked sponge will be used for the anode and cathode. The anode will be placed over the leg area of the motor cortex, on the lesioned side, with the medial border of the electrode placed laterally to Cz on the international electroencephalogram 10-20 system. The cathode will be placed above the contralateral orbit. The stimulation intensity wi
• Device Sham transcranial direct current stimulation (Sham-tDCS)
  Sham tDCS will be delivered by a constant-current electrical stimulator (DC-stimulator; Eldith, Ilmenau, Germany). Rectangular electrodes covered with a saline-soaked sponge will be used for the anode and cathode. The anode will be placed over the leg area of the motor cortex, on the lesioned side, with the medial border of the electrode placed laterally to Cz on the international electroencephalogram 10-20 system. The cathode will be placed above the contralateral orbit. The stimulation intensi
• Device Bilateral Transcutaneous electrical nerve stimulation (Bi-TENS)
  TENS will be delivered to the common peroneal nerve of both intact and paretic leg for 30 minutes using a 120z Dual-Channel TENS Unit (ITO Physiotherapy \& Rehabilittaion, Co, Ltd, Tokyo, Japan). The TENS stimulation will be at 100 Hz, with 0.2 ms square pulses at an intensity of twice the sensory threshold (defined as the minimum intensity at which subject reported feeling a tingling sensation and below the motor threshold as indicated by the absence of muscle twitching.
• Device Placebo transcutaneous electrical nerve stimulation (Placebo-TENS)
  Placebo-TENS will be applied to identical-looking TENS devices, with the electrical circuit disconnected inside the devices. Placebo-TENS will be delivered to the common peroneal nerve of both intact and paretic leg for 30 minutes that set at 100 Hz, with 0.2 ms square pulses.
• Behavioral Lower-limb task-oriented training
  The lower-limb task-oriented training comprises 5 exercises for 30 minutes, namely stepping up and down, heel lift a dorsiflexed position, partial squatting, gait re-education and transition training.

Primary outcome measures

• Paretic ankle dorsiflexor strength [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Paretic ankle plantarflexor strength [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Fugl-Meyer Assessment of Lower Extremity (FMA-LE) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]

Secondary outcome measures (10)

• 10-Meter Walk Test (10MWT) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Timed 'Up and Go' test (TUG) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Lower-extremity motor co-ordination test [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Gait Parameters (via GAITRite) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Berg Balance Scale (BBS) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Limits of Stability (LOS) Test [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Sensory Organization Test (SOT) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Cantonese version of Community Integration Measures (CIM-C) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• Foot & Ankle Disability Index Score (FADI) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]
• EQ-5D Visual Analogue Scale (EQ-5D VAS) [Time frame: Baseline (0 week), Mid-intervention (3 weeks), Post-intervention (6 weeks), 1-month follow-up (10 weeks)]

Eligibility criteria

Inclusion criteria

• are between 50 and 85 years of age;
• have had a single stroke more than 6 months and less than 15 years;
• have at least 5 degrees of active ankle dorsiflexion in the antigravity position;
• are able to walk 10 m independently, with or without a walking aid;
• are able to score 6 or higher out of 10 on the abbreviated mental test;
• have no skin allergies (e.g. redness or itchiness after application of the electrical stimulation pads) to electrical stimulation or electrodes;
• are able to follow instructions and give informed consent.

Exclusion criteria

• have any additional medical, cardiovascular or orthopedic conditions that would hinder their treatment or assessment;
• have a cardiac pacemaker;
• have aphasia or cognitive difficulties that may interfere with their comprehension of instructions;
• have had one or more epileptic seizures within the year prior to the date of inclusion in the study;
• have an intracerebral metal clip;
• have a major somatosensory deficit
• have any contraindication to tDCS;
• are currently involved in drug studies or other clinical trials.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Hong Kong · 1 center

• The Hong Kong Polytechnic University — Hong Kong

Identifiers

NCT: NCT06838013 · 2023_GRF_Ng

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗