I had a Chiropractor (the stereotypical Quack-o-practer) tell me he could cure my vertigo, which is the result of head trauma with neural damage, if I came in for treatment 3x / week for several weeks, then 2x / week...... Yeah right. He manipulated me into one of the worst ever migraines I ever had. Took a different Chiropractor to fix the dammage. Chiro #2, also would periodically work on my microscope neck (hours sitting at a 'scope), with me leaving his office feeling much better. Stuck with #2 until I moved away. #1 advertised heavily, #2 never advertised.

Osteopaths - I used to work in an Osteopathic hospital - it's a 4 year medical school, with internships, residencies, etc. just like traditional Medical school. Graduates are DO not MD. They are licensed as full fledged doctors. Some states have them as MD on the license. They tend to look at the body as a whole, and more keen on alternative medicine techniques.