Therapeutic Stimulation for Restoration of Function After Spinal Cord Injury

Abstract

Paralysis due to spinal cord injury can severely limit motor function and independence. This review summarizes different approaches to electrical stimulation of the spinal cord designed to restore motor function, with a brief discussion of their origins and the current understanding of their mechanisms of action. Spinal stimulation leads to impressive improvements in motor function along with some benefits to autonomic functions such as bladder control. Nonetheless, the precise mechanisms underlying these improvements and the optimal spinal stimulation approaches for restoration of motor function are largely unknown. Finally, spinal stimulation may augment other therapies that address the molecular and cellular environment of the injured spinal cord. The fact that several stimulation approaches are now leading to substantial and durable improvements in function following spinal cord injury provides a new perspectives on the previously "incurable" condition of paralysis.

Retraining Reflexes: Clinical Translation of Spinal Reflex Operant Conditioning

“…The latter pattern, also observed in stroke, contributes to locomotor impairments such as clonus and foot drop [123]. H-reflex measures have also been used in defining the effects of therapeutic interventions on reflex pathways (e.g., baclofen [124][125][126][127], botulinum toxin [128,129], locomotor training [130][131][132][133], cycling [134,135], muscle stretching [110,[136][137][138][139], therapeutic massage [140,141], whole body vibration [21,142], spinal cord stimulation [114,[143][144][145][146], transcranial direct current stimulation [147] and transcranial magnetic stimulation [27,[148][149][150][151]).…”

Novas perspectivas de fisioterapia respiratória em lesão medular - uma revisão sistemática

“…The modulation of electrical stimulation parameters can cause intermittent pressure on the paralyzed respiratory muscles, which contributes to increasing intra-abdominal pressure and influences peak cough flow, similar to the physiological bronchial hygiene mechanism. (12)(13) Based on the aforementioned issue, the objective of this systematic literature review was to identify and describe parameters and effects of surface electrical stimulation on respiratory muscle function among individuals with SCI, especially while coughing.…”

Trans-spinal direct current stimulation for the modulation of the lumbar spinal motor networks

“…Since DCS is usually applied at lower electric field amplitudes, the resulting post stimulation effect is subtle, and a study including multiple subjects is necessary to empirically optimize DC stimulation interventions. Whereas this is similar for the post stimulation effects of pulsed waveform protocols, due to the higher amplitude waveform an acute stimulation effect is visible [47,50]. This offers immediate neurophysiological feedback, which may readily be used for protocol optimization within a single experiment.…”

“…To mimic a spinal motoneuron response similar to that of a primary MEP, we simulate soleus voluntary contraction with a pulse input. Descending efferent input to the motoneuron pool is given by a single pulse Poisson distributed firing pattern, with a mean inter-spike-interval (ISI) of 3ms for 0 ms ≤ ‫ݐ‬ ≤ 5 ms [50] and infinite otherwise (for details, refer to [39]). Baseline synaptic maximum conductance was set to 700 nS.…”

“…For instance, in a study by Gerasimenko and colleagues, several subjects diagnosed with motor complete paralysis were able to partly regain voluntary movement control after an 18-week training program, including weekly transcutaneous pulsed, supra-threshold spinal stimulation in combination with pharmaceutical intervention. Thus, while the more substantial improvements in voluntary control have only been achieved after long periods of combined manual training and electrical stimulation [36][37][38][46][47][48][49], immediate acute effects can already be observed during the first application [47,50].…”