1) Winding Circle series by Tamora Pierce: Rosethorn suffered a brain injury (sort of) that left her with slurred speech. In the aftermath of that, Rosethorn's as opinionated as she always was, but has trouble making herself understood, most noticably in an emergency situation.

2) Chip Chase (Transformers G1) - declining offers from the Autobots to 'fix' his legs.