FES for Tremor Suppression

(Tremor Trial)

Overseen By Nitin Sharma

Age: 18+

Sex: Any

Travel: May Be Covered

Time Reimbursement: Varies

Trial Phase: Academic

Recruiting

Sponsor: North Carolina State University

Must not be taking: Neuromuscular junction drugs

Disqualifiers: Muscle weakness, Infection, Neuromuscular disorders, others

No Placebo Group

Trial Summary

What is the purpose of this trial?

This trial uses ultrasound imaging to study and understand hand tremors. It aims to help people with tremor disorders by accurately identifying involuntary muscle movements. The study includes both people with tremors and those without.

Do I need to stop my current medications for the trial?

The trial does not specify if you need to stop your current medications, but it excludes those using medications that affect the neuromuscular junction. It's best to discuss your specific medications with the trial coordinators.

What data supports the effectiveness of the treatment for tremor suppression using ultrasound imaging and electrical stimulation?

Research shows that ultrasound imaging can effectively visualize muscle activity and changes, which helps in monitoring and adjusting electrical stimulation for muscle strengthening and motor restoration. This suggests that combining ultrasound with electrical stimulation could be beneficial for controlling tremors by providing real-time feedback and personalized treatment adjustments. ^{1 2 3 4 5}

Is functional electrical stimulation (FES) safe for humans?

Research on functional electrical stimulation (FES) for tremor suppression shows it can be used safely in humans, with studies indicating it effectively reduces tremors in conditions like essential tremor and Parkinson's disease. However, there are practical limitations, such as controlling only one pair of muscles at a time, which may restrict its use to certain types of tremors. ^{6 7 8 9 10}

How does the FES treatment for tremor suppression differ from other treatments?

FES (Functional Electrical Stimulation) is unique because it uses electrical impulses to stimulate muscles, which can help suppress tremors by enabling controlled muscle movements. Unlike other treatments that might rely on medication or surgery, FES directly targets muscle activity and can be adjusted in real-time to manage muscle fatigue, making it a non-invasive and adaptable option for tremor management. ^{1 2 3 11 12}

Eligibility Criteria

This trial is for people aged 40-90 with Parkinson's Disease or tremor conditions, who have a rest tremor in their upper extremities. The tremor must be significant and re-emergent when holding a posture. Participants should not have other neuromuscular disorders, essential tremor, be on certain medications, or have muscle weakness.

Inclusion Criteria

I am between 40 and 90 years old.

I experience involuntary shaking in one or both of my arms.

Criterion: You must have a specific type of tremor that occurs when you hold an object, and it should start with a delay and grow in strength over a few seconds. The tremor should not be caused by anxiety, stress, cold temperature, or fatigue. We will give you time to relax before the test to help reduce these factors.

Exclusion Criteria

I have muscle weakness in my arm with tremors.

You have existing nerve or brain disorders.

I have been diagnosed with essential tremor by a specialist.

Trial Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo ultrasound imaging and functional electrical stimulation to analyze and suppress tremors

3 years

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Analysis and Suppression of Tremor During Grasp Using Ultrasound Imaging and Electrical Stimulation (Procedure)
• Electromyography (Behavioural Intervention)
• Functional Electrical Stimulation (FES) (Behavioural Intervention)
• Inertial Measurement Units (IMU) (Behavioural Intervention)
• Ultrasound Imaging (Behavioural Intervention)

Trial Overview The study tests how well ultrasound imaging combined with electrical stimulation can identify and suppress hand tremors versus current methods like medication or surgery. It aims to differentiate between voluntary movements and involuntary tremors for better treatment strategies.

Participant Groups

Group I: Tremor Group Experimental Treatment 4 Interventions

Individuals with either parkinson's disease or essential tremor will be recruited in this group

Group II: Able Body Group Experimental Treatment 4 Interventions

Individuals with no disorders will be recruited in this group

Who Is Running the Clinical Trial?

North Carolina State University

Lead Sponsor

Trials

38

Recruited

50,000+

University of North Carolina, Chapel Hill

Collaborator

Trials

1,588

Recruited

4,364,000+

Findings from Research

Ultrasound myography (UMG) is a new technique that uses Doppler ultrasound to measure muscle movement velocity, providing a noninvasive way to assess muscle response to electrical stimulation.

Preliminary results show that UMG can effectively measure nerve conduction velocities in the forearm, with significant improvements in response times after warming the hand, suggesting its potential for clinical applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ultrasound myography: application in nerve conduction velocity assessment and muscle cooling. Journée, HL., de Jonge, AB.[2019]

A new ultrasound imaging protocol was developed to visualize muscle contractions from neuromuscular electrical stimulation (NMES) in stroke patients, demonstrating its potential for assessing muscle activation during therapy.

The study involved 35 patients and found that the motor threshold for NMES was 23.4 mA, with minimal correlation to body mass index or subcutaneous fat thickness, suggesting that ultrasound can help tailor NMES treatments to individual patient needs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Using Portable Ultrasound to Monitor the Neuromuscular Reactivity to Low-Frequency Electrical Stimulation. Petraş, A., Drăgoi, RG., Pupazan, V., et al.[2021]

Ultrasound echogenicity has been shown to effectively indicate muscle fatigue during functional electrical stimulation (FES), demonstrating a strong linear relationship with fatigue levels in the tibialis anterior muscle during both isometric and dynamic movements.

This study, involving three human participants, suggests that using ultrasound as a fatigue indicator could improve the design of FES systems, allowing for better management of muscle fatigue during long-term tasks like walking.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ultrasound Echogenicity-based Assessment of Muscle Fatigue During Functional Electrical Stimulation. Zhang, Q., Iyer, A., Lambeth, K., et al.[2022]

Neuromuscular ultrasound is a non-invasive and painless technique that effectively diagnoses and monitors muscle and nerve disorders, making it a valuable point-of-care tool without the risks associated with ionizing radiation.

This technique allows for real-time visualization of muscle and nerve abnormalities, providing dynamic imaging capabilities that can enhance diagnosis and treatment, especially in cases where traditional methods like electromyography may not be suitable.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Neuromuscular Ultrasound: A New Tool in Your Toolbox. van Alfen, N., Mah, JK.[2019]

Muscle ultrasound is a non-invasive and real-time technique that can effectively visualize structural changes in muscles due to neuromuscular disorders, achieving predictive values of 90% for detecting these conditions, although sensitivity is lower in young children and metabolic myopathies.

This technique is particularly effective in identifying fasciculations and even smaller spontaneous muscle activities like fibrillations, surpassing the sensitivity of traditional methods like Electromyography (EMG), which suggests a promising expansion of muscle ultrasound in diagnosing peripheral nerve and muscle disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Skeletal muscle ultrasound. Pillen, S., van Alfen, N.[2022]

Functional electrical stimulation (FES) significantly reduced tremors in patients, achieving a 73% reduction in essential tremor, 62% in parkinsonian tremor, and 38% in cerebellar tremor associated with multiple sclerosis, demonstrating its efficacy across different types of tremors.

While the technique shows promise, its current limitation is that it can only control one pair of antagonist muscles at a time, which may restrict its use to patients with single-joint tremors, although combining it with mechanical orthoses could enhance its applicability.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Attenuation of pathological tremors by functional electrical stimulation. II: Clinical evaluation. Javidan, M., Elek, J., Prochazka, A.[2019]

Functional electrical stimulation (FES) significantly reduced upper limb physiological tremor in healthy subjects, with a decrease in tremor power spectral density by 62.18% and root mean square by 57.16%.

However, the presence of augmented visual feedback negated the positive effects of FES on tremor, indicating that visual cues can interfere with the benefits of electrical stimulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Augmented visual feedback counteracts the effects of surface muscular functional electrical stimulation on physiological tremor. Grimaldi, G., Fernandez, A., Manto, M.[2021]

The study demonstrated that closed-loop functional electrical stimulation (FES) can effectively suppress pathological tremors in the 2-5 Hz range by activating muscles out-of-phase, while minimally affecting normal movements in the 0-1 Hz range.

The research involved measurements of the forearm and hand's response to stimulation in multiple subjects, leading to configurations that balance tremor suppression with stability, suggesting potential for clinical application.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Attenuation of pathological tremors by functional electrical stimulation. I: Method. Prochazka, A., Elek, J., Javidan, M.[2022]

Functional electrical stimulation (FES) using electromyography (EMG) data can effectively control smooth and reproducible movements of the elbow, demonstrating its potential for rehabilitation.

The study highlights the advantages of using EMG-based stimulation data in FES, suggesting it could be a valuable technique for understanding and improving the functional anatomy of human extremities.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Study on the elbow movement produced by functional electrical stimulation (FES). Naito, A., Handa, Y., Handa, T., et al.[2019]

The adaptive band-pass filter (ABPF) shows promise for effectively estimating tremor during hand movements in real-time, which could enhance functional electrical stimulation (FES) systems designed to cancel pathological tremors.

In tests comparing ABPF to the established weighted-frequency Fourier linear combiner (WFLC) method, ABPF demonstrated faster adaptation and greater accuracy, suggesting it may be a superior choice for tremor extraction in patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Adaptive band-pass filter (ABPF) for tremor extraction from inertial sensor data. Popović, LZ., Sekara, TB., Popović, MB.[2010]

This study demonstrates that ultrasound imaging can effectively measure muscle fatigue induced by functional electrical stimulation (FES) in the tibialis anterior muscle, showing a strong correlation between ultrasound echogenicity signals and muscle fatigue levels during both isometric and dynamic contractions.

The findings suggest that using ultrasound-derived echogenicity as a real-time indicator of muscle fatigue could enhance the design of closed-loop FES systems, potentially improving rehabilitation outcomes for individuals with mobility impairments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Ultrasound Echogenicity as an Indicator of Muscle Fatigue during Functional Electrical Stimulation. Zhang, Q., Iyer, A., Lambeth, K., et al.[2022]

The study evaluated the effects of neuromuscular electrical stimulation (NMES) on muscle architecture in the quadriceps of seven healthy subjects, revealing that NMES-induced contractions significantly altered muscle thickness compared to voluntary contractions.

A strong correlation was found between rectus femoris (RF) thickness and knee joint angle during NMES, suggesting that monitoring RF thickness could help optimize NMES systems and assess muscle condition during stimulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sonomyography Analysis on Thickness of Skeletal Muscle During Dynamic Contraction Induced by Neuromuscular Electrical Stimulation: A Pilot Study. Qiu, S., Feng, J., Xu, J., et al.[2017]

References

1. England pubmed.ncbi.nlm.nih.gov

Ultrasound myography: application in nerve conduction velocity assessment and muscle cooling. [2019]

2. Switzerland pubmed.ncbi.nlm.nih.gov

Using Portable Ultrasound to Monitor the Neuromuscular Reactivity to Low-Frequency Electrical Stimulation. [2021]

3. United States pubmed.ncbi.nlm.nih.gov

Ultrasound Echogenicity-based Assessment of Muscle Fatigue During Functional Electrical Stimulation. [2022]

4. England pubmed.ncbi.nlm.nih.gov

Neuromuscular Ultrasound: A New Tool in Your Toolbox. [2019]

5. England pubmed.ncbi.nlm.nih.gov

Skeletal muscle ultrasound. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

Attenuation of pathological tremors by functional electrical stimulation. II: Clinical evaluation. [2019]

7. England pubmed.ncbi.nlm.nih.gov

Augmented visual feedback counteracts the effects of surface muscular functional electrical stimulation on physiological tremor. [2021]

8. United States pubmed.ncbi.nlm.nih.gov

Attenuation of pathological tremors by functional electrical stimulation. I: Method. [2022]

9. Japan pubmed.ncbi.nlm.nih.gov

Study on the elbow movement produced by functional electrical stimulation (FES). [2019]

10. Ireland pubmed.ncbi.nlm.nih.gov

Adaptive band-pass filter (ABPF) for tremor extraction from inertial sensor data. [2010]

11. Switzerland pubmed.ncbi.nlm.nih.gov

Ultrasound Echogenicity as an Indicator of Muscle Fatigue during Functional Electrical Stimulation. [2022]

12. United States pubmed.ncbi.nlm.nih.gov

Sonomyography Analysis on Thickness of Skeletal Muscle During Dynamic Contraction Induced by Neuromuscular Electrical Stimulation: A Pilot Study. [2017]