of patients received it. The majority of U.S. chiropractic schools and some schools in other countries teach the AMCT method, and an estimated 45,000 chiropractors worldwide use AMCT or some part of the technique. There have been a number of studies of AMCT, including case reports, clinical studies and controlled trials, but there are still unanswered questions. A few low-quality studies have suggested that the activator may be as effective as manual adjustment in treatment of back pain. A single high-quality study has suggested that activator-assisted manipulation directed by leg-length testing was significantly inferior to manual spinal manipulation guided by palpation and was more similar to the use of paracetamol for the treatment of low back pain. Graston technique Graston Technique (GT) is a trademarked therapeutic method for diagnosing and treating disorders of the skeletal muscles and related connective tissue. The method was started by David Graston and employs a collection of six stainless steel instruments of particular shape and size, which are used by practitioners to rub patients' muscles in order to detect and resolve adhesions in the muscles and tendons. Practitioners must be licensed by the parent corporation (Graston Technique, LLC.) in order to use the Graston Technique trademark or the patented instruments. Several examples of Graston treatment have been used in contact sports where scars and contusions are common. However, the Graston Technique has not been rigorously scientifically tested and its evidence basis and assumptions are considered questionable at best. There are no high quality clinical trials that validate the efficacy of the Graston Techniques. Koren Specific Technique Koren specific technique (KST) is a technique developed by Tedd Koren around 2004. While the technique is associated with chiropractic techniques, Koren has variously described it as an "analysis protocol" or "healthcare protocol". KST may use their hands, or they may use an electric device known as an "ArthroStim" for assessment and adjustments. KST can use different postures. The insurers Aetna, NHS Leeds West CCG, North Dakota Department of Human Services, and The Ohio State University cover other chiropractic techniques but exclude KST from coverage because they consider it to be "experimental and investigational." Aetna's policy states there is a lack of efficacy regarding this method. Gonstead technique The Gonstead technique is a chiropractic method that was developed by Clarence Gonstead in 1923. The technique focuses on hands-on adjustment and is claimed to expand "standard diversified technique" by removing