Trial Outcomes & Findings for Transspinal Stimulation Plus Locomotor Training for SCI (NCT NCT04807764)

Participants with SCI were recruited from various sources: Each site's existing databases of past research participants; people with SCI seen clinically at the James J. Peters VA Medical Center and Mount Sinai Medical Center; via flyers and webpage notices; and through various tabling events at local expositions and gyms that cater to people with SCI.

Transspinal Stimulation Plus Locomotor Training for SCI

Soleus H-reflexes following posterior tibial nerve stimulation with a 1-ms monophasic pulse were recorded with subjects seated and stimuli delivered every 1 s (1.0 Hz), 3 s (0.33 Hz), 5 s (0.2 Hz), 8 s (0.125 Hz), and 10s (0.1 Hz). Results for each interval vs 0.1 Hz shown.

Presynaptic inhibition was assessed with a conditioning pulse train of 4 pulses with 9 ms duration, delivered to the CPN at the C-T intervals of 20, 60, or 100 ms. These C-T intervals were selected because the reflex inhibition produced at the intermediate C-T intervals is predominantly presynaptic. The stimulus to the CPN was delivered at 1.27 ± 0.12 (21.8 ± 10.1 mA) and 1.4 ± 0.28 (21.8 ± 10.1 mA) TA motor threshold before and after treatment, respectively. Control and conditioned soleus H-reflexes were randomly recorded across the C-T intervals tested, and 15 H-reflexes were recorded at each C-T interval. For each participant at each timepoint, amplitudes across the 15 H-reflexes per C-T interval were averaged. Results are listed for each C-T interval, pre- and post-intervention.

To assess restoration of reciprocal Ia inhibition, soleus H-reflexes were recorded following common peroneal nerve (CPN) stimulation at short conditioning-test (C-T) intervals of 0, 1, 2, 3, and 4 ms. The stimulus to the CPN was delivered at 1.27 ± 0.12 (21.8 ± 10.1 mA) and 1.4 ± 0.28 (21.8 ± 10.1 mA) TA motor threshold before and after treatment, respectively. Control and conditioned soleus H-reflexes were randomly recorded across the C-T intervals tested, and 15 H-reflexes were recorded at each C-T interval. For each participant at each timepoint, amplitudes across the 15 H-reflexes per C-T interval were averaged. Results are listed for each C-T interval, pre- and post-intervention.

Neurophysiological measurements assessing changes in corticospinal excitability from the interventions by recording responses to single-pulse transcranial magnetic stimulation (TMS) at rest and during robotic-assisted stepping. The tibialis anterior resting motor threshold (RMT) was established and corresponded to the lowest TMS maximal stimulator output that induced reproducible evoked potentials of at least \~50 µV in 4 out of 5 consecutive single TMS pulses. RMTs (percentage of maximal stimulator output) are shown pre- and post-intervention.

Change in 10-meter timed test (seconds required to complete 10-meter walk) between baseline and post-intervention. Fewer seconds means faster (better) gait.

Changes in Berg Balance Scale score between baseline and post-intervention. Scale scores between 0 and 56. Higher scores mean better balance.

SCIM III Bladder and Bowel management subscores Bladder subscore rated 0-15 (higher means better bladder function). Bowel subscore rated 0-10 (higher means better bowel function).