I would like to know if its ok to consult a male doctor . I am afraid for purpose of proper diagnosis i may have to expose my leg upto knee… i have checked there is no female doctor under that specialty department.

If it is very necessary for a male doctor to examine you, then medically he can. as long as he doesn't come in contact with your body, and uses the medical tools to examine you and does not see your private parts .
this is if you really need to be seen by a male specialist