I suggest that you check the thread in this forum started recently by ScottSuff, who,by the way, is also in Tennessee; Knoxville, I think.

The injury you suffered as a youngster may have damaged nerve outlets in your cervical and thoracic spine that connect directly with the basal ganglia.
In fact, there is a condition known as thoracic outlet syndrome that manifests symptoms similar to PD.

It seems that certain chiropractors specialize in treating this problem. Replies by John Neuro to SS's posting identify some possibilities.

I also remember seeing some discussions recently about a group of surgeons in Spain who apparently have successfully treated numerous patients with this type of injury.
Try googling "thoracic outlet syndrome surgery".

Robert