FES to Improve Gait in CP

The goal of this proposal is to mitigate the typical decline in walking function experienced by children with cerebral palsy (CP) via a Functional Electrical Stimulation (FES)-assisted treadmill training intervention.

In this study, the investigators intend to use thier CP FES Gait Training System to assess the neurotherapeutic effects of an FES-assisted treadmill training intervention on walking performance in children with CP. The research design consists of a randomized, controlled, two-treatment study in which the control subjects will cross-over into one of the two treatment groups. An FES-assisted training group will undergo twelve weeks of FES-assisted treadmill training using a distributive practice protocol consisting of alternating bouts of walking with and without FES assistance, followed by over ground walking reinforcement. A treadmill-only training group will undergo the same training regimen without FES-assistance. Finally, a non-intervention group will serve as a control. The investigators will analyze treatment efficacy via functional and biomechanical and measures collected pre-training, post-training and after a twelve-week follow-up period.

Aim 1: Assess the neurotherapeutic effects of FES-assisted treadmill and treadmill-only training on walking function relative to each other and to the control group.

1.1 The FES-assisted treadmill and treadmill-only groups will demonstrate greater improvements in walking speed and walking distance than the control group post-training and at follow-up. The FES-assisted treadmill group will show greater improvements than the treadmill-only group.

1.2 The FES-assisted treadmill and treadmill-only groups will demonstrate greater improvement in walking energy efficiency than the control group post-training and at follow-up. The FES-assisted treadmill group will show greater improvement than the treadmill-only group.

1.3 The FES-assisted treadmill and treadmill-only groups will demonstrate greater improvements in GMFM, perceived functional mobility, quality of life and self-perception measures than the control group post-training and at follow-up. The FES-assisted treadmill group will show greater improvements than the treadmill-only group.

Aim 2: Assess the differential neurotherapeutic effects of FES-assisted treadmill and treadmill-only training on walking biomechanics. The investigators will measure these effects using instrumented motion capture.

2.1 The FES-assisted treadmill group will demonstrate greater improvements in gait kinematics in stance phase (higher peak hip and knee extension and lower peak ankle dorsiflexion) and swing phase (higher peak knee extension and larger knee excursion) than the treadmill only and non-intervention groups 2.2 The FES-assisted treadmill group will demonstrate greater improvements in lower extremity kinetics (lower hip and knee extensor moments and increased ankle plantarflexion power) than the treadmill only and non- intervention groups.

2.3 The FES-assisted treadmill group will demonstrate greater improvements in spatiotemporal gait parameters (increased step length and gait velocity, decreased step width and double support time) than the treadmill- only and control groups.

Aim 3: Identify predictive measures of training efficacy. 3.1 Pre-training walking speed and energy efficiency will correlate with improvements in walking performance measures of Aim 1.

3.2 Increased neuroprosthetic correction of gait biomechanics measures achieved by FES will be positively correlated with walking performance measures of Aim 1.

Eligibility Criteria:
Inclusion Criteria:

* Age 10-18
* Diagnosis of spastic diplegic CP
* Gross Motor Functional Classification Scale (GMFCS) level I-III
* Hip migration \< 40%
* Displays crouch, equinus, or jump type gait
* At least 0° passive dorsiflexion range of motion (can come to a neutral position)
* Sufficient visuoperceptual, cognitive and communication skills
* Seizure-free or well-controlled seizures
* No other neurological or musculoskeletal disorders (e.g. dystonia, severe scoliosis, hip instability)
* Ability to travel to University of Delaware or Shriners Hospital for children multiple times per week for training and assessment
* Ability to communicate pain or discomfort
* Ability to consent (if 18 years old) or obtain parent/guardian consent (if under 18)

Exclusion Criteria:

* Diagnosis of athetoid or ataxic CP
* Scoliosis with primary curve \> 49%
* Spinal fusions extending into pelvis
* Lower Extremity (LE) joint instability or dislocation
* Severe tactile hypersensitivity
* LE botulinum (Botox) injections in the past 6 mo.
* Implanted medical device contraindicative of FES
* Pregnancy
* Severe LE spasticity (Modified Ashworth Scale score of 4 or greater)
* History of pulmonary disease limiting exercise tolerance (Asthma Control screen)
* History of cardiac disease (AHA screen)
* Excessive LE joint pain during walking
* Severely limited joint range of motion / irreversible muscle contractures, i.e.\> 10°knee flexion, \>15° hip flexion contractures, or \>5° plantarflexion contractures
* LE surgery or significant injury within 1 yr.