The American Andrew Taylor Still (1828-1917) invented osteopathy about 120 years ago and propagated it as a panacea. He postulated that almost all diseases are based on a dysfunctional musculoskeletal system. The treatment of this system is the only correct therapy. In the United States, osteopaths later evolved into medically fully trained physicians. Everywhere else - including Germany - osteopaths have to be classified as alternative practitioners.
In Germany, the job title "Osteopath" is actually illegal, and the title "D. O.” has no legal meaning.