Quantifying Energetic Demands of Walking for People With Cerebral Palsy

Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), Gillette Children's Specialty Healthcare

The purpose of this study is to examine the underlying mechanisms that contribute to high energy costs for people with cerebral palsy (CP) as they walk. The investigators will characterize the cost landscape of children with CP, quantifying the magnitude of cost (net nondimensional oxygen consumption) associated with walking and common sub-tasks of walking, such as supporting and stabilizing the body.

Children with CP use large amounts of energy to walk and move, leading to fatigue and limiting participation. For people with CP the energetic cost of walking is on average over two times higher than typically-developing (TD) peers. This means that for people with CP, walking is as tiring as jogging or climbing stairs. An energetic cost of this magnitude restricts activities of daily living (ADL) and causes exhaustion. While the investigators and many others have sought to reduce these energetic costs through surgical interventions, rehabilitation, orthotics, or other assistive devices, these strategies have failed to result in meaningful reductions in energy. To design strategies that successfully reduce walking costs, the investigators must first understand the underlying mechanisms contributing to elevated cost in people with CP. This basic-science research will provide the foundation to create evidence-based strategies to decrease energy costs, minimize fatigue, and increase quality of life for people with CP and other neurologic injuries.

Children meeting inclusion/exclusion criteria without a diagnosis of cerebral palsy or other condition.

Participants will complete a standard gait and motion analysis at varying levels of harness support and stabilization (low, moderate, and high levels).

Three-dimensional gait kinematics to estimate body position and orientation, including trunk and lower limb

Spasticity measured by Modified Ashworth Scale (0 no increase in tone - 4 rigid in flexion or extension)

Lower extremity strength measures by the manual muscle test (0 no muscle contraction - 5 typical muscle function)

Inclusion Criteria for Cases: 8-17 years old Diagnosed with bilateral cerebral palsy Gross Motor Function Classification System II No surgery within the last 9 months No current baclofen pump or explantation in the last 2 months No botulinum toxin or phenol injections in the last 2 months Had a prior gait and motion analysis at Gillette Children's Specialty Healthcare Participant and caregiver able to speak and read English Ability to follow instructions Inclusion Criteria for Controls: 8-17 years old Participant and caregiver able to speak and read English Ability to follow instructions

Campbell J, Ball J. Energetics of walking in cerebral palsy. Orthop Clin North Am. 1978 Apr;9(2):374-7. No abstract available.