Neuromodulation to Enhance Motor Function in HSP

Noninvasive Spinal Cord Neuromodulation to Enhance Motor Function in Individuals With Hereditary Spastic Paraplegia

Hereditary spastic paraplegia (HSP) is a rare neurological condition that causes stiffness, weakness, and difficulty walking due to damage in the nerves that control movement. This study will test whether a noninvasive form of spinal cord stimulation, called transcutaneous spinal cord stimulation (tSCS), can improve walking and reduce muscle stiffness in adults with HSP.

In this study, participants will receive tSCS twice a week for 8 weeks. The stimulation is delivered through self-adhesive electrodes placed on the skin over the lower back and does not require surgery. Each session will last about one hour. After the treatment period, participants will be followed for an additional 8 weeks without stimulation to see whether any improvements are maintained. Researchers will measure walking speed, walking endurance, muscle stiffness, and overall disease severity. Additional tests will explore changes in bladder and bowel function and muscle strength.

Study Overview

• Status: Recruiting
• Conditions: Hereditary Spastic Paraplegia
• Intervention / Treatment: Device: transcutaneous spinal cord stimulation

• Study Type: Interventional
• Enrollment (Estimated): 15
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Rahul Sachdeva, PhD; Phone Number: 8592574888; Email: rahulsachdeva@uky.edu

Study Locations

• United States
  • Kentucky
    • Lexington, Kentucky, United States, 40506
      • Recruiting
      • University of Kentucky
      • Contact: Rahul Sachdeva, PhD; Phone Number: 8592574888; Email: rahulsachdeva@uky.edu
      • Contact: Vivek K Pandey, PhD; Phone Number: 8592574888; Email: vivek.pandey@uky.edu

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Clinical diagnosis of hereditary spastic paraplegia (genetic confirmation if available).
• Stable medications for spasticity and other neurologic symptoms for =4 weeks prior to enrollment.
• Able to participate in study visits and assessments with or without assistive devices.
• If ambulatory: able to walk at least 10 meters with or without an assistive device.
• If wheelchair user: able to perform seated mobility tasks and transfers required for assessments.
• Capacity to provide informed consent and follow study procedures, with an ability to communicate and understand instructions in English

Exclusion Criteria:

• Implanted electronic devices (e.g., pacemaker, deep brain stimulator, intrathecal pumps).
• Severe cardiopulmonary disease that would make participation unsafe.
• Open skin lesions or severe dermatologic conditions at electrode sites.
• Pregnancy or plans to become pregnant during the intervention period.
• Diagnosed with Primary Lateral Sclerosis (PLS) or another neurological condition that affects walking, such as stroke, multiple sclerosis (MS), or a recent surgery on legs.
• Unable to participate in basic movement or mobility assessments, even with their usual mobility device (such as a wheelchair, walker, or cane). People who use wheelchairs or other mobility aids can participate if they can complete the study's mobility assessments in their usual way.
• Cognitive or psychiatric conditions that make it difficult to give informed consent or follow study instructions.
• Diagnosed with Urinary Tract Infection (UTI), either acute or ongoing, before or at the time of study enrollment.
• Diagnosed with epilepsy.
• Participation in another interventional clinical trial that could affect mobility or spasticity during the study.
• A recent change (within the last 4 weeks) in medications or treatments that affect spasticity or movement (for example: baclofen, tizanidine, botulinum toxin injections).
• Expect to start or change treatments for spasticity or mobility during the study period.
• Any condition judged by the investigator to pose excess risk or confound outcomes.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Participants with Hereditary Spastic Paraplegia; Participants will undergo 16 transcutaneous spinal cord stimulation (tSCS) sessions over 8 weeks	Device: transcutaneous spinal cord stimulation; a non-invasive spinal neuromodulation system will deliver stimulation as high-frequency pulsed current using frequencies within a predefined range; Other Names: SCONE

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in 10-Meter Walk Test (10MWT)	10MWT assesses walking speed over a 10-meter walkway at a comfortable and maximum safe pace. Timing occurs between 2 and 8 meters to exclude acceleration/deceleration, with two trials averaged per speed. Assistive devices are allowed	Baseline, Weeks 1, 4, 8, and 16
Change in 6- Minute Walk Test (6MWT)	6MWT evaluates walking endurance by measuring the total distance walked over six minutes. Patients are instructed to walk as far as possible at their own pace, with rests allowed if needed. The total distance reflects functional capacity and stamina, which are often affected in HSP due to progressive spasticity and weakness.	Baseline, Weeks 1, 4, 8 and 16
Change in Modified Ashworth Scale (MAS)	measures muscle spasticity by assessing resistance to passive muscle stretch through the range of motion and grades the muscle tone on a 0-4 scale based on the resistance felt. MAS 0-4 scale: 0: No increased muscle tone 1: Slight increase in tone; catch and release at the end of the range 1+ : Slight increase; catch followed by minimal resistance through < half the range 2: More marked increase through most of the range, but the limb still moves easily 3: Considerable increase in tone; passive movement is difficult 4: Limb is rigid in flexion or extension	Baseline, Weeks 1, 4, 8, and 16
Change in Spastic Paraplegia Rating Scale (SPRS)	The Spastic Paraplegia Rating Scale (SPRS) is a validated clinical outcome measure used to assess disease severity in individuals with spastic paraplegia. The scale consists of 13 items evaluating gait, spasticity, muscle strength, coordination, and functional impairment. Each item is scored to yield a total score ranging from 0 to 52, where a score of 0 indicates no neurological disability and higher scores reflect increasing severity of impairment, with 52 representing the most severe disease manifestation.	Baseline, Weeks 1, 4, 8, and 16

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in HSP- Self Notion and Perception (HSP-SNAP) questionnaire	HSP-SNAP is a questionnaire used to assess the self-perception of individuals diagnosed with hereditary spastic paraplegia (HSP). HSP-SNAP includes 12 questions, with 2 items dedicated to each symptom dimension (stiffness, weakness, imbalance, reduced endurance, fatigue, and pain). Each pair of items for a given dimension includes both positive and negative responses to prevent automatic answers. The HSP-SNAP employs a 5-point Likert scale (1 = strongly disagree, 2 = disagree, 3 = neutral, 4 = agree, 5 = strongly agree). To account for both positive and negative items, scoring is as follows: for items with a positive tone, the score is calculated as "patient's score minus 1" (pt score-1); for negative items, the score is "5 minus the patient's score" (5-pt score). The overall score is the sum of all item scores, ranging from 0 to 48. A higher score indicates better well-being and milder symptoms.	Baseline, Weeks 1, 4, 8, and 16
Change in Sit-to-stand test	Participants will be asked to perform a sit-to-stand task, whereby they will be told to stand up and sit down on a stool at their own self-selected pace. Sit-to-Stand performance, measured as the time and kinematic characteristics of sit-to-stand transition (average of two trials) obtained using motion capture analysis.	Baseline, Weeks 1, 4, 8, and 16
Change in Bilateral isometric knee strength	Bilateral isometric knee strength will be obtained with three, 5-sec maximal voluntary isometric contractions (MVIC) separated by one-minute rest. Knee strength, measured as peak knee extensor torque obtained using isokinetic dynamometry (Biodex), expressed in Newton-meters (Nm), with higher values indicating greater muscle strength.	Baseline, Weeks 1, 4, 8, and 16
Change in knee pain	Knee pain during knee strength test is recorded on an 11-point visual analog scale (0=no pain and 10 most pain possible).	Baseline, Weeks 1, 4, 8, and 16
Change in Joint Kinematics via Three-dimensional (3D) gait analysis	3D Gait Analysis will be performed using a 14-camera motion capture system, a wireless Electromyography (EMG) system, and 3 in-ground force plates. We will track walking speed using timing gates. Wireless EMG sensors will be placed on the vastus lateralis, rectus femoris, and vastus medialis to assess muscle activation during the gait trials. The outcomes will include joint kinematics (hip, knee, and ankle,).	Baseline, Weeks 1, 4, 8, and 16

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Neurogenic Bladder Symptom Score (NBSS)	The Neurogenic Bladder Symptom Score (NBSS) is a validated, disease-specific patient-reported outcome measure designed to assess lower urinary tract symptoms in individuals with neurogenic bladder. The questionnaire evaluates symptom severity across three domains, including incontinence, storage and voiding symptoms, and bladder-related consequences, as well as a global quality-of-life item. Individual items are scored on ordinal response scales, and summed to generate a total score ranging from 0 to 74, with higher scores indicating greater urinary symptom severity and impact on daily functioning.	Baseline, Weeks 1, 4, 8, and 16
Change in Neurogenic bowel dysfunction score (NBD Score)	The Neurogenic Bowel Dysfunction Score (NBDS) is a validated clinical questionnaire used to assess the severity and impact of bowel dysfunction in individuals with neurological conditions, including spinal cord injury. The instrument evaluates multiple domains of bowel function, including frequency of defecation, constipation, fecal incontinence, use of medication or mechanical assistance, and impact on quality of life. Individual item scores are summed to yield a total score ranging from 0 to 47, with higher scores indicating more severe bowel dysfunction and greater impact on daily living.	Baseline, Weeks 1, 4, 8, and 16.
Change in Metabolic/protein profiling	Approximately 10 mL of venous blood samples will be collected and processed for metabolomic/lipid profiling and biomarker assays	Baseline, Weeks 1, 4, 8, and 16

Collaborators and Investigators

• Sponsor: Rahul Sachdeva
• Collaborators: Spastic Paraplegia Foundation
• Investigators: Principal Investigator: Rahul Sachdeva, PhD, University of Kentucky

Study record dates

Study Major Dates

• Study Start (Actual): April 9, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): February 1, 2028

Study Registration Dates

• First Submitted: February 10, 2026
• First Submitted That Met QC Criteria: February 10, 2026
• First Posted (Actual): February 18, 2026

Study Record Updates

• Last Update Posted (Actual): April 22, 2026
• Last Update Submitted That Met QC Criteria: April 17, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Neuromuscular Diseases; Genetic Diseases, Inborn; Peripheral Nervous System Diseases; Neurodegenerative Diseases; Congenital Abnormalities; Heredodegenerative Disorders, Nervous System; Nervous System Malformations; Polyneuropathies; Hereditary Sensory and Motor Neuropathy; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Spastic Paraplegia, Hereditary
• Other Study ID Numbers: 109294

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Deidentified individual participant outcomes data will be published in peer-reviewed journals.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes