For centuries scientists, physicians, and even philosophers have long believed that the body's spinal cord is at the root of many ailments that have nothing to do with back or neck pain.

But the birth of the chiropractic profession was not to occur until the late-19th century—September 18, 1895, to be exact—in the small offices of the Palmer Cure & Infirmary in Davenport, Iowa.

Late that day, Canadian-born Daniel David Palmer was in his office trying to have a conversation with the building's janitor, Harvey Lillard.

Palmer noticed that Lillard was nearly deaf, and asked the man what caused him to lose his hearing. Lillard didn't know, but told Palmer his hearing began diminishing after a back injury he sustained while stooping in a cramped position. Lillard remembered hearing a "pop" in his back, and suffered hearing loss for years after that.

It was a revelation that capped what Palmer had long suspected—an indubitable connection between the spine and disease—that misalignment of the spinal column interferes with normal nerve function, and thus, leads to a host of maladies. Palmer suspected that if he were able to return the popped vertebrae in Lillard's back to its original position, it would also restore his hearing. Using a technique called the "spinous process," Palmer gently repositioned the vertebra with a firm thrust.

Lillard's hearing began to return. Over the next week, Palmer continued his spinal manipulation treatment on Lillard; each day his hearing gradually improved. Palmer coined a term for his new technique: chiropractic from the Greek words chiro, meaning hand, and practic, meaning practice. He dedicated his practice from that point forward to use of the new therapy.

In the ensuing months, Palmer treated flu, sciatica, migraine headaches, stomach complaints, epilepsy, and heart trouble with adjustments he called "hand treatments"—all without the use of drugs, medications, or surgery.

Despite Palmer's early successes, chiropractic adjustments were not readily accepted by the medical community. Palmer was later indicted for practicing medicine without a license and was sentenced to 105 days in jail and ordered to pay a $350 fine.

Palmer is the author of two well-known books: The Science of Chiropractic (1906) and The Chiropractor's Adjuster (1910). He died in 1913 at the age of 68 in Los Angeles.

His son, Bartlett Joshua, carried on his father's work and was instrumental in getting chiropractic recognized as a licensed profession.

In the 20th century, the chiropractic profession grew into a respected branch of the healing arts, largely through research and recognition by the government and medical community. Here are some milestones:

• The American Chiropractic Association was founded in 1922 and merged with the Universal Chiropractors Association to form the National Chiropractic Association (NCA) in 1930.
• In 1944, the Chiropractic Research Foundation (CRF) was created by the National Chiropractic Association to promote and obtain research funding.
• In the 1960s, the National Chiropractic Association once again became the American Chiropractic Association (ACA) and the CRF became the Foundation for Accredited Chiropractic Education, whose main purpose was to assist chiropractic colleges in gaining accreditation.
• In 1974, the U.S. Department of Health, Education and Welfare recognized the Council on Chiropractic Education (CCE), and the Foundation for Accredited Chiropractic Education was reorganized as the Foundation of Chiropractic Education and Research (FCER).
• In 1975, the U.S. Department of Health Education and Welfare sponsored a research conference on spinal manipulation, an event that raised awareness of the need for research. Out of that, the Chiropractic Research Council (CRC) was born to assimilate research directors from the nation's chiropractic colleges.
• In 1979, the Foundation of Chiropractic Education and Research expanded its research program and established a competitive scientific review process for submitted proposals.
• Today, 14 English peer-reviewed chiropractic journals routinely publish the results of chiropractic research.