This article is from the Aviation FAQ, by Geoffrey G. Peck firstname.lastname@example.org with numerous contributions by others.
There are pilots in all kinds of aircraft flying all over the world with
some kind of disability, including amputees, paraplegics, etc.
If you have a condition which might preclude you from getting a
medical certificate, contact the medical services department of
AOPA (see below). They will be glad to assist you, whether or not you
are a member.
We also are fortunate to have an expert in our midst on the net, Dr.
Richard Kaplan, M.D., CFI, AME. Please contact him with your questions
directly at <email@example.com>; he's also offered to provide flight
physicals and flight instruction (you provide the airplane) to
disabled netters at no charge. He's located ~50nm SE of Pittsburgh PA.