Spinal adjustment and chiropractic adjustment are terms used by chiropractors to describe their approaches to spinal manipulation, as well as some osteopaths, who use the term adjustment.
Spinal adjustments were among many chiropractic techniques invented in the 19th century by Daniel David Palmer, the founder of Chiropractic. Claims made for the benefits of spinal adjustments range from temporary, palliative (pain relieving) effects to long term wellness and preventive care. Despite anecdotal success, there is not yet scientific evidence that spinal adjustment is effective against disease.
In a section titled "Spinal Manipulation: The Chiropractic Adjustment", chiropractic authors and researchers Meeker and Haldeman write that the core clinical method that all chiropractors agree upon is spinal manipulation, although chiropractors much prefer to use the term spinal "adjustment", a term which reflects "their belief in the therapeutic and health-enhancing effect of correcting spinal joint abnormalities." (p. 218)
The International Chiropractor's Association (ICA) states that the "chiropractic spinal adjustment is unique and singular to the chiropractic profession", and that it "is characterized by a specific thrust applied to the vertebra utilizing parts of the vertebra and contiguous structures as levers to directionally correct articular malposition. Adjustment shall be differentiated from spinal manipulation in that the adjustment can only be applied to a vertebral malposition with the express intent to improve or correct the subluxation, whereas any joint, subluxated or not, may be manipulated to mobilize the joint or to put the joint through its range of motion... Chiropractic is a specialized field in the healing arts, and by prior rights, the spinal adjustment is distinct and singular to the chiropractic profession." One author claims that this concept is now repudiated by mainstream chiropractic. The definition of this procedure describes the use of a load (force) to specific body tissues with therapeutic intent. This ‘load’ is traditionally supplied by hand, and can vary in its velocity, amplitude, duration, frequency, and body location (p. 218) and is usually abbreviated HVLA (high velocity low amplitude) thrust.
The intention of a chiropractic adjustment is to affect or correct the alignment, motion and/or function of a vertebral joint. Specifically, they are intended to correct "vertebral subluxations", the term given to the signs and symptoms that are said by chiropractors to result from abnormal alignment of vertebrae. (p. 218) This intention forms the legal and philosophical foundation of the profession, and US Medicare law formulates it in this manner: