This research project is being conducted to investigate changes in secondary impairments, functional mobility skills, and gait variables in children with spasticity following selective percutaneous myofascial lengthening. The research project proposed here will be the first to use instrumented three-dimensional motion analysis to investigate the effects of selective percutaneous myofascial lengthening on gait kinematics and kinetics. The objectives of the study are to:

1. Compare gait kinematics and kinetics in children and young adults with lower extremity spasticity before and after selective percutaneous myofascial lengthening to determine the effects of this procedure on functional mobility.
2. Identify changes in impairments and activity limitations following selective percutaneous myofascial lengthening .
3. Identify changes in a family or caregivers perceived quality of life after their child's selective percutaneous myofascial lengthening .

The aim of this study is to identify and describe the specific changes in secondary musculoskeletal impairments, activity limitations, and gait kinematics and kinetics after a selective percutaneous myofascial lengthening procedure. Gait kinematics and kinetics includes the motion of joints and body segments, and force and power, at each lower extremity joint, respectively. The results of this study will provide preliminary information on how this form of soft tissue lengthening affects functional mobility skills in children with spasticity. The study is expected to run for two years and the primary study endpoint is when participants have completed their second post- operative data collection session.

Inclusion Criteria:

• Scheduled for an selective percutaneous myofascial lengthening procedure,
• Between the ages of 4.0 and 20.11 years old,
• Lower extremity spasticity,
• Able to ambulate 50 feet without a rest, with or without an assistive device, and with or without ankle foot orthoses (AFOs) and
• Able to follow one step directions.

Exclusion Criteria:

• Botox injections into any lower extremity muscle within three months of the scheduled selective percutaneous myofascial lengthening procedure,
• Lower extremity orthopedic surgery within 6 months of the scheduled selective percutaneous myofascial lengthening procedure,
• Visual impairment that interferes with maintaining a straight path while ambulating,
• Uncontrolled seizure disorder
• A change in medication that affects spasticity or ability to follow one step directions within three months of the scheduled selective percutaneous myofascial lengthening procedure.

Children between the ages of 4.0 and 20.11 years