Have you tried adjusting the handlebars to make your hands higher?
Some experts say that the back of your forearm should follow a flat line into the back of your hand to stop numbness, tingling and other physical problems experienced whilst riding.
It seems to me the best way to get numbness and tingling in your hands and arms is to put on 14-18" ape hangers.

Though if you are tall, mini-apes might be workable. Even with taller risers. Look at some Z-bars.
I'm 5'9", so I'd probably have to stand up on my floor boards all day to ride around with 18" apes.