The principle is to direct focused ultrasound directly at the disc that has started to bulge outward and press against the nerves. When the disc cartilage warms up, its collagen fibers shrink, so the cartilage no longer bulges so much. This means that it no longer presses against the nerves that cause the pain.
Johan Persson’s dissertation work involves the design of an ultrasound transmitter, temperature measurements in the laboratory, and simulation of the temperature distribution in the disc during ultrasound treatment-some of the key steps in the development of this new technique. In traditional slipped disc operations, the damaged disc is opened up. The operation requires hospital care and a long period of sick leave, and it also involves a risk of complications. Ultrasound treatment, on the other hand, is done with a local anesthetic, takes only six minutes, and requires no hospital stay. If the method lives up to its promise, it will therefore be both more attractive to patients and cheaper for health care.
According to Björn Strömqvist, professor of orthopedics, the ultrasound method is intended for slipped discs that are not too large (so-called covered, non-perforated hernias). It is being tested now in a so-called multi-center study in Sweden, Germany, South Korea, Italy, and Turkey. The study is still in a very early phase, but preliminarily it seems that two thirds of the slipped disc patients treated have been helped by ultrasound.
Under the direction of Björn Strömqvist, the Section for Orthopedics at Lund will also study whether the method can be used for so-called disc degeneration. This is an age-related change in the cartilage discs of the vertebrae that is even more common than slipped discs.