Short-Term Transcutaneous or Epidural Spinal Stimulation for Enabling Motor Function in Humans With SCI

Primary outcomes

1. Electromyography

   Time frame: Through study completion; an average of 5 months.

   Change in voltage measurements in major muscle groups below the level of injury. Specifically, change in soleus root mean square voltage during standing with and without stimulation.

2. Foot Pressure

   Time frame: Beginning of intervention to end of intervention, an average of 17 days.

   Change in measurements of foot pressure in kilograms through shoe-insole pressure sensors.

3. Somatosensory Evoked Potentials

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Measurements of change in voltage in the conduction of electricity through the peripheral nerves, cervical and lumbosacral spinal cord, deep brain structures, and sensory cortex, using surface electrodes.

4. Transcranial Magnetic Stimulation Motor Evoked Potentials

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Measurement of the threshold percentage change in voltage between pre-intervention and post-intervention in the first trapezius or deltoid muscle activated.

5. Injury Severity: International Standards for Neurological Classification of Spinal Cord Injury

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Change sensory and motor function impairment using the American Spinal Injury Association Impairment Scale. Individuals are classified from A" (complete SCI) to "E" (normal function). 28 dermatomes and 10 key muscles are assessed bilaterally. Summed results produce overall sensory and motor scores and combine with evaluation of anal sensory and motor function in determination of AIS classification. Sensory scores are rated 0 (sensation absent) to 2 (normal), bilaterally for each of 28 dermatomes. Muscle function is rated 0 (total paralysis) to 5 (active movement, full range of motion against significant resistance) for each myotome. Upper Extremity Motor Subscores and Lower Extremity Motor Subscores are scored from 0 to 50; the ASIA Motor Score is scored from 0 to 100. The presence of deep anal pressure and voluntary anal contraction are assessed as a yes/no; absence of these, in addition to sensory scores of 0 at S4-5 indicate a Complete injury (otherwise, the injury is Incomplete).

6. Patient-reported Bowel Function

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Measurement of change in bowel function using the Neurogenic Bowel Dysfunction Score. Answers to qualitative questions are rated from 0 to 5, with a higher number indicating more problematic symptoms, and totaled for a score which categorizes severity of neurogenic bowel symptoms. The total score ranges between 0 and 44 points. A higher total score indicates more severe bowel symptoms.

7. Patient-reported Bladder Function

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Measurement of change in bladder function using the Neurogenic Bladder Symptom Score. Answers to qualitative questions are rated from 0 to 5, with a higher number indicating more problematic symptoms, and totaled for a score which categorizes severity of neurogenic bladder symptoms. The total score can range from 0 (no symptoms at all) to 74 (maximum symptoms).

8. Male Patient-reported Sexual Function (1)

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Measurement of change in erectile dysfunction using the Sexual Health Inventory for Men (SHIM). Answers to qualitative questions are rated from 0 to 5, with a higher number indicating better erectile function, and totaled for a score which categorizes severity of erectile dysfunction. Total score can range from 1 to 25, with a lower number indicating more severe erectile dysfunction.

9. Male Patient-reported Sexual Function (2)

   Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

   Measurement of change in erectile dysfunction using the International Index for Erectile Function (IIEF). Answers to qualitative questions are rated from 0 to 5, with a higher number indicating better erectile function, and totaled for a score which categorizes severity of erectile dysfunction. Total scores range from 5 to 25, with a lower score indicating more severe erectile dysfunction.

10. Female Patient-reported Sexual Function

    Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

    Measurement of change in sexual function using the Female Sexual Function Index (FSFI). Answers to qualitative questions are rated from 0 to 5, with a higher number indicating better sexual function, and totaled for a score which categorizes severity of sexual dysfunction.

11. Spasticity

    Time frame: Assessed at Baseline, 4 Weeks, 8 Weeks, and 20 Weeks; change from Baseline at week 20 reported.

    Change in measurements of spasticity using the Spinal Cord Injury Spasticity Evaluation Tool (SCI-SET). Answers to qualitative questions are rated from -3 to +3, with a higher positive number indicating more helpful symptoms, and a lower negative number indicating more problematic symptoms. Questions may also be answered as not applicable (N/A), which do not generate a score. Scores are totaled for a score which categorizes the overall positive or negative impact of a subject's spasticity symptoms. Total score can range from -105 (negative impact) to +105 (positive impact), and the score is averaged by total positive or negative score divided by the number of applicable answers.

12. Neurostimulation User Experience

    Time frame: End of intervention, an average of 4 weeks

    Rating of the subject's perception of individual aspects of spinal stimulation using the User Experience Questionnaire (UEQ), a survey including 26 descriptive terms and their antonyms. A scoring scale ranging from 1 to 7 determines how closely the subject feels the term or its antonym applies to the intervention, with lower numbers indicating agreement with the term, and higher numbers indicating agreement with the antonym. The terms and antonyms describe a positive and negative perception of each item.

    Subscales grouping terms into like categories average scores into a 7 point range from -3 to +3, with negative averages associated with negative perceptions, and positive averages associated with positive perceptions.

13. Overground Ambulation [as Appropriate to the Subject]

    Time frame: Baseline, 4 Weeks, 8 Weeks, and 20 Weeks

    Measurement of changes in overground mobility as measured by the Modified 6 Minute Walk Test. Trainers will assess the distance in meters which the subject can cover in 6 minutes, with a greater distance characterizing better overground mobility.

14. Trunk Stability

    Time frame: Beginning of intervention to end of intervention, an average of 17 days, 8 weeks post beginning of intervention, 20 weeks post beginning of intervention; change from beginning of intervention at week 20 reported.

    Changes in trunk stability based on stable forward reach measured in centimeters, with a greater distance of forward reach characterizing greater trunk stability. Specifically, change in forward reach at the end of the study when comparing stimulation assisted reach and non-stimulation assisted reach.

15. Neurostimulator Lead Location and Migration [Epidural Group Only]

    Time frame: Pre-intervention and 4 weeks post-intervention

    Evaluation of current array location via CT.

16. Bladder Function Testing

    Time frame: Beginning of study, prior to initiating intervention; End of 4 weeks of intervention.

    Change in measurements of bladder function (end fill detrusor value) utilizing a urodynamic test consisting of a filling phase and a voiding phase cystometrogram along with perineal patch muscle electromyography.