How can I get rid of a rib hump?

Depends. If the hump is in an amenable location, surgical resection of the piece of rib can make the protruding rib shape disappear. This is purely a cosmetic procedure, though. You can have chronic pain after the procedure if the nerves that run under the ribs are damaged severely. Also, many insurances will not pay for this as it is only cosmetic. If you are still interested, check with your doctors.