Reflex Training for Spinal Cord Injury

Overseen By Blair Dellenbach, MSOT

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Medical University of South Carolina

Must be taking: Antispasticity medications

Must not be taking: Antidepressants

Disqualifiers: Motoneuron injury, Cardiac condition, Neurological condition, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 39

25 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to evaluate how well a new reflex training system, Spinal Reflex Operant Down Conditioning, assists people with chronic spinal cord injuries who experience leg spasticity (muscle stiffness and spasms). The focus is on reducing exaggerated reflexes in the legs, which can hinder walking. Participants will attend multiple sessions over six months to determine if the new system improves reflex control as effectively as the previous system. Suitable candidates have had a stable spinal cord injury for at least a year, can walk at least 10 meters using a walker, crutches, or cane, and experience leg spasticity. As an unphased trial, this study offers a unique opportunity to contribute to innovative research that could enhance the quality of life for those with spinal cord injuries.

Will I have to stop taking my current medications?

The trial does not require you to stop taking your current medications. However, your medications, including any for spasticity, should remain stable during the study. Changes in medication are unlikely but will be monitored and recorded.

What prior data suggests that this reflex training system is safe for individuals with spinal cord injury?

Research has shown that spinal reflex operant down conditioning is generally safe for both humans and animals. Studies have not identified any major safety issues with this method. By reducing overactive reflexes, it can help with conditions like muscle stiffness. Most participants have tolerated the treatment well, with no serious side effects reported. This evidence suggests that the treatment is safe and well-tolerated for those considering joining a clinical trial. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about Spinal Reflex Operant Down Conditioning because it offers a novel approach to managing spasticity in individuals with chronic incomplete spinal cord injury (SCI). Unlike traditional treatments for spasticity, which often rely on medications like baclofen or physical therapies to manage symptoms, this technique directly targets the hyperactive spinal stretch reflex pathway. By down-conditioning the soleus H-reflex, it aims to reduce the exaggerated reflex activity that characterizes spasticity. This method not only has the potential to be more effective but could also provide longer-lasting relief without the side effects associated with medication.

What evidence suggests that this reflex training system is effective for spinal cord injury?

Research has shown that training certain spinal reflexes can improve walking and balance in people with incomplete spinal cord injuries. This trial will use the new Spinal Reflex Operant Down Conditioning system to reduce overactive reflexes, potentially helping those with muscle stiffness gain better control over their movements. In some past cases, this type of reflex training led to noticeable improvements in movement for people with spinal cord injuries. However, if the reflex training was not successful, improvements in movement were not observed. Overall, this approach has shown promise in enhancing mobility for those with certain types of spinal cord injuries. ^{1 2 3 6 7}

Who Is on the Research Team?

Aiko Thompson, PhD

Principal Investigator

Medical University of South Carolina

Are You a Good Fit for This Trial?

This trial is for individuals with chronic incomplete spinal cord injury who can walk at least 10 meters, have leg spasticity, and are medically stable. They must be able to consent and not expect medication changes during the study. Excluded are those with unstable health, cognitive impairments, other neurological conditions, daily use of certain electrical stimulation devices, motoneuron injuries, serious heart issues, inability to test lower limb mobility or weight bearing, recent deep vein thrombosis or pregnancy.

Inclusion Criteria

My spinal cord injury above T11 has been stable for over a year.

Medical clearance to participate

My current medications are expected to stay the same during the trial's start period.

Exclusion Criteria

I have a history of heart issues, like a heart attack or use a pacemaker.

I have had a deep vein thrombosis in the last 6 months.

I cannot perform tests that require walking or standing.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Baseline

Participants complete 6 baseline sessions to measure initial reflex activity

2 weeks

6 visits (in-person)

Conditioning

Participants undergo 30 conditioning sessions to down-condition the soleus H-reflex

10 weeks

30 visits (in-person)

Follow-up

Participants are monitored for changes in spasticity, muscle strength, and functional independence

3 months

3 visits (in-person)

What Are the Treatments Tested in This Trial?

Interventions

• Spinal Reflex Operant Down Conditioning

Trial Overview The trial tests a reflex training system designed to reduce the size of targeted muscle reflexes in people with spinal cord injuries. Participants will undergo about 45 sessions over six months to see if this method can help manage spasticity in their legs by conditioning their spinal reflexes.

How Is the Trial Designed?

Group I: Validation of the new training system Experimental Treatment 1 Intervention

The researchers will measure changes in H-reflex size achieved with the use of the new system and compare these measures with the existing results in 25 spastic individuals with chronic incomplete SCI. Each participant completes 6 baseline sessions and 30 conditioning sessions. In the 30 conditioning sessions, the soleus H-reflex will be down-conditioned to decrease the activity of the hyperactive spinal stretch reflex pathway in people with spasticity that is characterized by exaggerated reflex activity. It is anticipated that the magnitude of reflex change obtained with the use of the new system would be greater or at least the same as the bench-marked values from the previous studies that used the old prototype reflex conditioning system.

Who Is Running the Clinical Trial?

Medical University of South Carolina

Lead Sponsor

Trials

994

Recruited

7,408,000+

National Institute of Neurological Disorders and Stroke (NINDS)

Collaborator

Trials

1,403

Recruited

655,000+

Published Research Related to This Trial

The corticospinal tract (CST) is crucial for both the acquisition and maintenance of a conditioned decrease in the H-reflex, a model for studying spinal cord reflexes, as shown in a rat study involving various spinal cord transections.

Other major spinal pathways, such as the dorsal column and lateral column, do not play a significant role in this process, suggesting that targeting the CST could lead to new strategies for enhancing recovery of motor functions after spinal cord injuries.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Probable corticospinal tract control of spinal cord plasticity in the rat. Chen, XY., Wolpaw, JR.[2017]

In a study involving 12 participants with chronic spastic hemiparesis after stroke, operant down-conditioning successfully reduced the soleus H-reflex size by an average of 30% in half of the participants, indicating potential for reflex modification even in cases of supraspinal injury.

Participants whose H-reflex decreased also showed improvements in walking speed, with an average increase of 0.14 m/s, suggesting that reflex down-conditioning can enhance motor function in stroke patients, although the overall success rate was lower than in individuals with incomplete spinal cord injury.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Operant down-conditioning of the soleus H-reflex in people after stroke. Thompson, AK., Gill, CR., Feng, W., et al.[2023]

A new conditioning protocol targeting the swing-phase of locomotion in individuals with incomplete spinal cord injury (SCI) significantly reduced the size of the H-reflex more quickly and effectively than traditional steady-state methods, with effects lasting at least 6 months.

This swing-phase conditioning not only decreased the reflex but also improved walking speed and muscle activity, suggesting a promising approach for enhancing recovery in SCI and potentially other movement disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

H-reflex conditioning during locomotion in people with spinal cord injury. Thompson, AK., Wolpaw, JR.[2022]

Operant-conditioning protocols that reward specific electromyographic responses can effectively modify spinal reflex pathways, leading to changes in reflex activity and associated behaviors in both animals and humans.

In individuals with partial spinal cord injuries, these conditioning techniques can enhance locomotion and promote widespread beneficial plasticity in the nervous system, suggesting a promising therapeutic approach for rehabilitation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Targeted neuroplasticity for rehabilitation. Thompson, AK., Wolpaw, JR.[2018]

Operant conditioning protocols can effectively modify spinal reflexes, which are fundamental behaviors, providing valuable insights into the mechanisms of learning.

These protocols can also promote neural plasticity, potentially aiding in the recovery of motor skills like walking in individuals with spinal cord injuries or related disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The simplest motor skill: mechanisms and applications of reflex operant conditioning. Thompson, AK., Wolpaw, JR.[2021]

Operant conditioning of spinal reflexes has evolved over 35 years from basic science to a promising rehabilitation therapy for spinal cord injuries, showing significant potential for enhancing nervous system plasticity.

Initial studies in both animal models and humans indicate that reflex conditioning can lead to exciting therapeutic outcomes, highlighting the importance of basic research in informing clinical applications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Operant conditioning of spinal reflexes: from basic science to clinical therapy. Thompson, AK., Wolpaw, JR.[2022]

Operant conditioning of spinal reflexes can significantly improve motor function in individuals with incomplete spinal cord injury (SCI), as shown by down-conditioning the soleus H-reflex, which led to increased walking speed and symmetry in patients.

The study indicates that targeting specific reflex pathways not only enhances the targeted reflex but also promotes widespread recovery, resulting in noticeable improvements in daily activities such as walking, balance, and reduced spasticity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Restoring walking after spinal cord injury: operant conditioning of spinal reflexes can help. Thompson, AK., Wolpaw, JR.[2022]

Spinal stretch reflexes (SSRs) can be conditioned to be either smaller or larger, as shown in studies with monkey models and able-bodied humans, indicating a potential for rehabilitation strategies.

Conditioning techniques have been successful in reducing hyperactive SSRs in spinal-cord-injured patients with some residual control, suggesting that these methods could improve movement control in this population.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Plasticity in the Central Nervous System: Operant Conditioning of the Spinal Stretch Reflex. Segal, RL.[2016]

In a study involving individuals with chronic incomplete spinal cord injury, down-conditioning the soleus H-reflex through 30 sessions led to significant improvements in locomotion, with two-thirds of participants experiencing a decrease in H-reflex size and reporting faster, more symmetrical walking.

The results indicate that reflex-conditioning protocols can effectively enhance recovery of motor function by targeting specific spinal pathways, suggesting potential for personalized rehabilitation strategies in spinal cord injuries and other movement disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Operant conditioning of a spinal reflex can improve locomotion after spinal cord injury in humans. Thompson, AK., Pomerantz, FR., Wolpaw, JR.[2022]

Citations

1. clinicaltrials.gov clinicaltrials.gov/study/NCT05094362

NCT05094362 | Operant Conditioning of Spinal Reflexes ... The purpose of this study is to validate the capacity of a reflex training system to change the size of the targeted reflex. For this, the researchers are ...

2. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC6095771/

Clinical Translation of Spinal Reflex Operant Conditioning Thus, in humans with incomplete SCI, down-conditioning ... Operant conditioning of a spinal reflex can improve locomotion after spinal cord injury in humans.

3. withpower.com withpower.com/trial/phase-paralysis-3-2022-8acf6

Reflex Training for Spinal Cord Injury Research shows that operant conditioning of spinal reflexes can improve walking and balance in people with incomplete spinal cord injuries by targeting specific ...

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4167198/

Restoring Walking after SCI: Operant Conditioning of Spinal ... Locomotion did not improve in the subjects in whom H-reflex down-conditioning was not successful or in subjects in whom the H-reflex was simply ...

5. frontiersin.org frontiersin.org/journals/integrative-neuroscience/articles/10.3389/fnint.2014.00025/full

Operant conditioning of spinal reflexes: from basic science ... Operant conditioning of a spinal reflex can improve locomotion after spinal cord injury in humans. J. Neurosci. 33, 2365–2375. doi: 10.1523/JNEUROSCI.3968 ...

6. scitrialsfinder.net scitrialsfinder.net/trials/NCT05094362

Operant Conditioning of Spinal Reflexes Training Syste This is a clinical trial recruiting individuals with chronic incomplete spinal cord injuries to test the effect of an exercise training intervention on ...

7. wearesrna.org wearesrna.org/blog/operant-conditioning-rehabilitation-studies/

Operant Conditioning Rehabilitation Studies | SRNA Blog Initial results have seen improved walking and lessened foot drop. The third study addresses neuropathic pain after spinal cord injury. People ...