I could be totally off here, but when I was working on my essay and interview for entry to Chiro this is what I learnt.

Essentially, Chiropractors & Osteopaths do a lot of the same physical adjustments. Their philosophies are different - in what they believe is the main "control" of the body (so to speak). Physiotherapists are all about Musculo-skeletal MANIPULATION whereas chiropractors & osteopaths are about ADJUSTMENT. Not sure about osteopaths, but chiropractors are supposedly very against the practises of physotherapy.

Chiropractic is based in the nervous system being the key control of the body's health and well being. Whereas Osteopathy focus on an unimpeded Circulatory system for the health of the nervous system, and in turn the human body. IYKWIM?

Chiros and Osteos can both be used for maitenance and repair. So if you were wanting alignment to prevent discomfort or SPD etcetera, I would suggest a weekly or fortnightly session, but best to be discussed with the practitioner you choose.

HTH.