In most cases they are used for the treatment of functional joint blocks, which are painful and restrict movement, and cause additional pathological reflectory changes, mainly aching points, zones of hyperalgia and muscle spasms. The purpose of the treatment is the release of the motoric segment (in the area of the spine), or the restoration of joint motion (in joints), but also the adjustment of muscle tone, and treatment of the so-called trigger points, which many times cause the pain, muscle weakness or limited motorics. Manipulation has to be done exclusively by a doctor, specially trained and licensed.