Spinal cord stimulation and assisted treadmill stepping
Motor complete spinal cord injury (SCI) results in the loss of voluntary control of muscles below the lesion level. One promising rehabilitation strategy to recover motor function after SCI is body-weight supported and assisted treadmill stepping repetitively applied for an extended period of time (locomotor training). However, recovery of motor function was found to be variable depending on the severity of injury. In regards to locomotor recovery specifically, the synergistic effects of treadmill stepping, pharmacological interventions and spinal cord stimulation have been demonstrated in animal experiments.
A previous Wings for Life-funded project found that non-invasive, surface electrode-based spinal cord stimulation (SCS) increased and modulated lower limb muscle activities produced during (manually assisted) treadmill stepping in motor complete and incomplete SCI participants. Functional motor patterns and changes in kinematics were produced only in incomplete SCI subjects with residual voluntary locomotor capabilities.
This project proposes to improve the rhythmic motor outputs in motor complete SCI people. Changes of the motor output by variation of the applied tonic drive (SCS site, strength, frequency) will be studied and the regulative impact of (load, speed, range of hip joint angle) will be examined.
The significance of the proposal lies
a) scientifically, better understanding of the interplay of tonic signals, and patterned feedback signals associated with stepping in the generation of rhythmic locomotor-like outputs.
b) therapeutically, this thrust is a necessary step towards the application of this method in clinical practice