There have been several places that treated my nephew, as a child, young adult, and teen.

Dupont, in Delaware, or is ot New Jersey? Hershey Hospital in, Hershey PA. (THe doctor here was a pediatrician) Jefferson hospital, Philadelphia, as a teen, did an extension when he grew the spine collapsed.

The extension rod to make him the corrected height and fix spine was giving him several inches in height. The neurogist in Hershey, and a hospital in New York, did a loosening for the muscle spasicity.

Another thought we did not use them, likely for distance reasons is Johns Hopkins in Maryland. That would be my first choice if coming from out of country as they are considered tops in the field. I am not sure if Dr.Paul Carson does the work with CP, but top neurologist.

Hope you can find some answers, there may be other forums here that may have more members with this problem in their family.
Dianne.