Post polio syndrome. Or orthopedic?

I had polio when I was 3/4 years old. I recovered with mild impact and may be 20% impact on my right leg. I can walk and run like everyone else. People can't recognise until I tell them. There is a muscle difference between 2 legs. I was happy for all these years but from the past 2- 3 years there was a muscle shake above my knee. It come and goes, mostly at night. And from the past 2 months my leg has had some kind of pain. I have consulted a couple of neurologists, they reviewed and did EMG, NCV, MRI spine tests. After that test, they confirmed there is no new problem, might be some kind of weakness. But my problem is still there and it has increased. How can I be sure it's not post polio syndrome. Whom do I need to consult? Neurologist or orthopedic? I am stressed with this problem, don't know where to go.. pls advise