I don't know. There's no reason to be. I assume it is the feeling of professional embarrassment. Perhaps it's the desire to be more than just a podiatrist. To be a foot and ankle surgeon. But, you can't escape the word, it's part of your degree Doctor of Podiatric Medicine. So you have 2 choices, abandon the word and live a lie, or embrace the word and attempt to elevate the perception thereof. I choose the latter.
Even some say, podiatric physician, as if that is more of a doctor than a podiatrist??? You don't see cardiologists calling themselves cardiologic physicians. You don't see gynecologists calling themselves vagina and uterus surgeons. It's more embarrassing to attempt to be something you're not. You are a podiatrist, which is a physician and surgeon of the foot (and ankle).
Be proud to be a podiatrist.