Also called MDT – Mechanical diagnosis therapy, McKenzie exercise is a therapeutic method based on examination of patients suffering from back pain, leg pain and spinal problems. It is a comprehensive method of musculoskeletal system care. Robin McKenzie (1931 – 2013), a physiotherapist from New Zealand, developed this method in the late 1950s. Physiotherapist assigns patients into groups defined by a common problem, and determines the treatment. Sometimes the treatment may be time-consuming and requires a lot of patience, but it has the advantage of being inexpensive. Mechanical diagnosis therapy is therefore reliable and very popular method of patient examination.