Segmental Mechanisms of Transcutaneous Spinal Cord Stimulation for Spasticity Control

Study Overview
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Brief Summary
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The aim of the pilot study is to gain first insights into the interaction of transcutaneous spinal cord stimulation with the altered activity of intraspinal circuits associated with spinal spasticity. The main goal is to evaluate the validity of the chosen measures and to generate a data base for statistical planning of a subsequent clinical study.

Official Title
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Carry-over Effects of Transcutaneous Spinal Cord Stimulation for Spasticity Control on Inhibitory Circuits of the Spinal Cord: a Pilot Study

Conditions
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Spinal Cord Injuries

Intervention / Treatment
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* Device: transcutaneous spinal cord stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: written informed consent prior to participation for participants with intact CNS: • no previous neurological or musculoskeletal disorders for participants with spinal cord injury: Spinal cord injury due to trauma ≥ 12 months post-spinal cord injury complete or incomplete spinal cord injury classified as grade C or D on the American Spinal Injury Association Impairment Scale (AIS) neurological level of spinal cord injury: C3-T10 preserved tendon and cutaneo-muscular reflexes in the lower limbs Exclusion Criteria: other neuromuscular diseases, e.g., amyotrophic lateral sclerosis (ALS), Parkinson's disease, Guillain-Barré syndrome, muscular dystrophy active implants (e.g., cardiac pacemaker, drug pump) passive implants at vertebral level T10 or caudal (e.g., metal screws/plates for surgical stabilization of spinal fractures) active infections or diseases, pressure sores dermatological issues at the stimulation site malignant diseases heart insufficiency (NYHA III-IV) potential pregnancy (pregnancy test to be conducted in women of child bearing age before application of transcutaneous spinal cord stimulation)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: transcutaneous spinal cord stimulation|noninvasive electrical stimulation of the human lumbar spinal cord|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postsynaptic inhibition | reciprocal inhibition of the soleus H-reflex | pre-intervention to 2 hours post-intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Presynaptic inhibition | induced D1 inhibition and ongoing presynaptic inhibition of the soleus-H reflex | pre-intervention to 2 hours post-intervention | 
| H_max/M_max | Ratio of the maximum H reflex and the maximum M wave | pre-intervention to 2 hours post-intervention | 
| Low-frequency depression | rate-dependent depression of the soleus H-reflex | pre-intervention to 2 hours post-intervention | 
| Evaluation of lower-limb spasticity | surface-electromyography based assessments | pre-intervention to 2 hours post-intervention |