Chiropractic is well established in the United States, Canada, and Australia. It overlaps with other manual-therapy professions such as osteopathy and physical therapy. Most who seek chiropractic care do so for low back pain. Back and neck pain are considered the specialties of chiropractic, but many chiropractors treat ailments other than musculoskeletal issues. Many chiropractors describe themselves as primary care providers, but the chiropractic clinical training does not support the requirements to be considered primary care providers, so their role on primary care is limited and disputed. Chiropractic has two main groups: "straights", now the minority, emphasize vitalism, "innate intelligence", and consider vertebral subluxations to be the cause of all disease; "mixers", the majority, are more open to mainstream views and conventional medical techniques, such as exercise, massage, and ice therapy.
Studies have not confirmed the effectiveness of prolotherapy or sclerotherapy for pain relief, used by some chiropractors, osteopaths, and medical doctors, to treat chronic back pain, the type of pain that may come on suddenly or gradually and lasts more than three months. The therapy involves injections such as sugar water or anesthetic in hopes of strengthening the ligaments in the back.