Implant for Walking After Incomplete SCI

Inclusion Criteria:

* Between the ages of 18-75
* Non-ventilator dependent paralysis resulting from injuries such as: cervical/thoracic spinal cord injuries affecting the trunk and/or lower limbs
* Impairment classification of AIS B, C, or D (preservation of sensation and/or some motor function) with weakness in trunk and/or lower extremity muscles
* Unable to walk faster than 0.8m/s during a 10m walk test
* Gait deviation such as reduced peak hip, knee, and/or ankle range of motion during stance or swing phases due to motor impairment
* Time post injury greater than six months
* Innervated and excitable lower extremity and trunk musculature
* Adequate social support and stability
* Willingness to comply with follow-up procedures
* Appropriate body habitus (height and weight within acceptable limits as determined by study physician)
* Neurologically stable as determined by a physician

Exclusion Criteria:

* Significant fracture risk or history of spontaneous fractures
* History of heterotopic ossification at the hip, knee, or ankle
* Non-English speaking
* Insufficient upper extremity function to use an assistive device (e.g. walker or cane)
* Females who are pregnant
* Current pressure injury that would be exacerbated by study activities
* Uncontrolled spasticity that would interfere with study activities
* Significant range of motion limitations that would compromise study activities
* History of vestibular dysfunction, balance problems, or spontaneous falls
* Disorder or condition that require MRI monitoring
* Acute and/or untreated orthopedic issues that would prevent weight bearing or exercising implanted muscles such as a dislocation or fracture
* Acute and/or chronic medical problems left untreated or not controlled that would increase risk by using stimulation such as cardiac abnormalities, immunological/pulmonary/renal/circulatory compromise
* Uncontrolled diabetes or hypertension
* Presence of a demand pacemaker, cardiac defibrillator, or neuroprosthesis system with components in the legs
* Any other medical or psychological condition that would be a contraindication

Implant eligibility criteria

• In addition to all of the above, the participant must be able to fully support their body weight in standing with an assistive device prior to implantation.