Injectable Ventral Spinal Stimulator Evokes Programmable and Biomimetic Hindlimb Motion

Area of Science:

• Biomedical Engineering
• Neuroscience
• Regenerative Medicine

Background:

• Spinal cord neuromodulation shows promise for restoring motor function after injury or disease.
• Existing spinal stimulators face limitations, including suboptimal placement and invasive surgical requirements.

Purpose of the Study:

• To develop and evaluate a novel, flexible, and stretchable spinal stimulator for minimally invasive implantation.
• To assess the efficacy of this device in restoring motor function in a mouse model.

Main Methods:

• A nanoscale-thin, flexible spinal stimulator was designed and implanted via a catheter into the ventral spinal space of mice.
• Stimulation threshold currents and motor pool recruitment were compared between ventrolateral and dorsal epidural implants.
• Specific stimulation patterns were used to elicit hindlimb movements.

Main Results:

• Ventrolaterally implanted devices demonstrated significantly lower stimulation thresholds and more precise motor pool recruitment compared to dorsal epidural implants.
• The stimulator successfully induced functionally relevant and novel hindlimb movements.
• The minimally invasive implantation technique proved effective.

Conclusions:

• This flexible, injectable spinal stimulator offers a promising alternative to current neuromodulation technologies.
• The ventrolateral approach enhances stimulation efficiency and motor control.
• The technology holds significant translational potential for treating spinal cord injury and neuromotor disorders.