Improving Ambulatory Community Access After Paralysis

In a surgical procedure electrodes are inserted into muscles of the lower extremities to
correct hip, knee and ankle function. The electrode leads are connected to an implanted pulse
generator located in the abdomen. After a typical post-operative period of two to five days,
the recipient will be discharged home for two to six weeks of moderate activity. Following a
6 week period of laboratory exercise and training, functional use of the neuroprosthesis will
begin at home and in the community with follow-up evaluations at 1, 3, 6 and 12 months.
Laboratory assessments include walking speed and distance, physiologic cost, muscle strength,
measure of spasticity, and gait analysis with and without stimulation. A number of
self-reporting instruments are administered to capture individual's participation, quality of
life and various aspects of perceived community ambulation.

Inclusion Criteria:

- problems walking because of paralysis for more than 6 months

- weak hip flexors and extensors or excessive tone

- weak ankle dorsiflexors (muscles bringing the foot up)

- weak plantar flexors (ankle muscles for push-off)

- foot drop that is causing "dragging" or "catching" toes during walking

- swinging the leg sideways or hiking the hip to clear affected leg during stepping

- endurance to walk at least 10 ft with minimal assistance

- hip extension range to neutral

- hip flexion range greater or equal to 90 degrees

- ankle range to neutral

- sufficient upper extremity function to use a walking aid

- muscles respond to electrical stimulation

Exclusion Criteria:

- cardiac arrythmias

- demand pacemaker

- pregnancy

- Parkinson's disease

- traumatic brain injury

- autoimmune deficiency

- uncontrolled diabetes

- significant edema of the affected limb

- active pressure ulcers or open wounds

- sepsis or an active infection

- severe osteoporosis

- uncontrolled seizures

- moderate depression