The aim of this study is to improve the manufacturing techniques of hip brace in preventing progressive hip displacement in patients with severe cerebral palsy, through the measurement of patient's physical size using a 3D scanner.

1. Design : Prospective Study
2. Setting: Hospital rehabilitation department and Home
3. Intervention: Before starting the study, radiologic and clinical evaluation were performed. After measuring the patient's exact physical size by applying a 3D scanner, we manufacture hip brace in preventing progressive hip displacement in patients with severe cerebral palsy. After wearing for a week, follow-up radiologic and clinical evaluation were performed.
4. Main outcome measure 1) Primary outcome: right, left, both hip MI 2) Secondary outcomes: the hip and knee joint range of motion (ROM), pain intensity, satisfaction and discomfort score for the hip brace, quality of life (QOL) of the patients and their caregivers, and the wearability test.

Inclusion Criteria:

1. diagnosis of cerebral palsy
2. age 1-15 years
3. GMFCS Level IV, V
4. quadriplegia, or diplegia for more than 6 months
5. Patients who have written consent with permission from the child and caregiver.

Exclusion Criteria:

1. Patients who did not agree to participate in the study
2. Patients who refused the examination
3. Patients who had hip surgery experience
4. Patients who were scheduled to undergo surgery during the clinical study
5. Patients who could not be measured with a 3D scanner