How to help ankle pain from fractured growth plate injury that happened over a year ago?

See a specialist. There are different types of growth plate fractures. If the fracture involved the ankle joint then there may be damage in the joint cartilage causing the pain. Any misalignment of a bone in the joint can also cause pain. You need to see a specialist who will evaluate and possibly take an MRI to see if there is any damage in the joint.
Growth Plate Fractur. 1st of all see a specialist....If the growth plate was injured a year ago.....The problem may not be a growth plate, or it may be related to the injury. There is no way to tell without x_rays and possibly an mri. See a specialist and get checked out...Only then will we be able to give you a sold answer.