Transcutaneous Tibial Nerve Stimulation for Spinal Cord Injury Neurogenic Bladder (TTNS1yr)

The University of Texas System (UT)

Status: Enrolling

Conditions: Spinal Cord Injuries

Treatments: Device: Fixed-dose TTNS Protocol; Device: Variable-dose TTNS Protocol 2 x week; Device: Variable-dose TTNS Protocol 5 x week

Study type: Interventional

Funder types: Other

Identifiers

NCT04350359

HSC-MS-19-0756

Details and patient eligibility

About

The purpose of this study is to determine if electric stimulation to the leg, called transcutaneous tibial nerve stimulation (TTNS), can improve bladder outcomes in acute spinal cord injury.

Full description

The purpose of this study is to see how well TTNS works at preventing incontinence in people with paraplegia from SCI that perform intermittent catheterization to empty their bladder. This study will compare the effectiveness of TTNS at 2 doses, fixed-dose and variable-dose. It will also evaluate the frequency of use, 2 days weekly compared to 5 days weekly.

Based on our pilot trials, tibial nerve stimulation protocols use submotor current intensity with a duration of 200 µs and a frequency of 20Hz. The experimental group will use a submotor "variable dose." The fixed-dose group will use submotor at current intensity at 1mA and designated as "fixed-dose."

TTNS will be used 5 days weekly, per our pilot trial. At 4-months post-SCI, the subject will be instructed to switch to 2x daily if he or she was randomized into the variable dose group of 2 days weekly and thus continue to doing so for the remainder of study participation. Because there is support in the literature for reduced doses of tibial nerve stimulation required for maintenance (1-3x weekly), the RCT includes this frequency comparison arm. All subjects will continue for 1-year post-SCI.

Additionally, we are collecting surveys to help identify characteristics of people (resilience and confidence) and adherence to medication and TTNS use throughout the study.

Enrollment: 120 estimated patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• 18-75 years old
• Traumatic or non-traumatic SCI
• Admitted to inpatient rehabilitation within 6 weeks
• T9 level of injury and above who are at greatest risk of morbid NGB
• Regionally located to allow follow-up
• English or Spanish speaking

Exclusion criteria

• History of genitourinary diagnoses (i.e. prostate hypertrophy, overactive bladder, cancer, etc.)
• History of central nervous system disorder (i.e. prior SCI, stroke, brain injury, Parkinson's disease, MS, etc.)
• History of peripheral neuropathy
• pre-SCI symptoms of peripheral neuropathy (numbness and/or tingling in feet, sharp/jabbing/burning pain in feet, sensitivity to touch, lack of coordination, muscle weakness, etc.)
• Pregnancy
• Known injury to the lumbosacral spinal cord or plexus, or pelvis with associated neuropathy
• concern for tibial nerve pathway injury
• absence of toe flexion or autonomic dysreflexia during electric stimulation test
• Potential for progressive SCI including neurodegenerative SCI, ALS, cancer myelopathy, Multiple sclerosis, transverse myelitis

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Factorial Assignment

Masking: Single Blind

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120 participants in 3 patient groups

Variable-dose TTNS Protocol 5 x week

Active Comparator group

Description:

TTNS protocol: Electrodes 2 inch by 2 inch will be placed according to anatomic landmarks, with the negative electrode behind the internal malleolus and the positive electrode 10cm superior to the negative electrode, verified with rhythmic flexion of the toes secondary to stimulation of the flexor digitorum and hallicus brevis. The intensity level will be set to the amperage immediately under the threshold for motor contraction. If there is no contraction seen, patients will be excluded. In addition, if the patient perceives pain, the intensity will be lowered until comfortable. Stimulation frequency of 20 Hz and pulse width of 200ms in continuous mode will be used. All participants will be instructed to use the device for 30 minutes, 5 days per week for the first 4 months post-sci.

Treatment:

Device: Variable-dose TTNS Protocol 5 x week

Fixed-dose TTNS protocol

Active Comparator group

Description:

Fixed-dose protocol: Toe flexion will be attempted, as in the TTNS protocol. Then the stimulation will be reduced to 1 mA for 30 minutes. Both variable-dose TTNS and fixed-dose TTNS protocol participants will be instructed to use the device for 30 minutes, 5 days per week.

Treatment:

Device: Fixed-dose TTNS Protocol

Variable-dose TTNS Protocol 2 x week

Active Comparator group

Description:

At the 4 month CMG, subjects initially randomized into the variable dose protocol of 2 x weekly will start doing so for the remainder of the study.

Treatment:

Device: Variable-dose TTNS Protocol 2 x week