If the xray is showing a problem with the hips, I would suggest a board certified orthopedic surgeon....not a neurologist.
You might want to ask your vet for an opinion on that...and a referral. You can find an ortho surgeon at:
American College of Veterinary Surgeons
Now, IF there is nothing wrong bone wise and there are neuro deficits, a neurologist makes sense....just seems to me that
if they are seeing something on the xray then it is ortho.