Frontier physician Andrew Taylor Still founded the profession as a rejection of the prevailing system of medical practices throughout the 19th century. Still's techniques relied on manipulation of joints and bones, to diagnose and treat illness, and he called his practices "osteopathy". By the middle of the 20th century, the profession had moved closer to mainstream medicine, adopting modern public health and biomedical principles. American "osteopaths" became "osteopathic medical doctors", ultimately achieving full practice rights as medical doctors in all 50 states, including serving in the United States Armed Forces as physicians and surgeons.