Chiropractic is a form of alternative medicine mostly concerned with the diagnosis and treatment of mechanical disorders of the musculoskeletal system, especially the spine. Proponents claim that such disorders affect general health via the nervous system.These claims are not backed by any evidence. The main chiropractic treatment technique involves manual therapy, especially spinal manipulation therapy (SMT), manipulations of other joints and soft tissues. Its foundation is at odds with mainstream medicine, and chiropractic is sustained by pseudoscientific ideas such as subluxation and “innate intelligence”.
Numerous controlled clinical studies of treatments used by chiropractors have been conducted, with conflicting results. Systematic reviews of this research have not found evidence that chiropractic manipulation is effective, with the possible exception of treatment for back pain. A critical evaluation found that collectively, spinal manipulation was ineffective at treating any condition. Spinal manipulation may be cost-effective for sub-acute or chronic low back pain but the results for acute low back pain were insufficient.The efficacy and cost-effectiveness of maintenance chiropractic care are unknown. There is not sufficient data to establish the safety of chiropractic manipulations.It is frequently associated with mild to moderate adverse effects, with serious or fatal complications in rare cases.There is controversy regarding the degree of risk of vertebral artery dissection, which can lead to stroke and death, from cervical manipulation.Several deaths have been associated with this technique and it has been suggested that the relationship is causative, a claim which is disputed by many chiropractors.