Musculo-skeletal ultrasound in rheumatology practice.

In rheumatology ultrasound is a relatively new but rapidly developing field, and now forms an important part of curriculum of rheumatology training programs in European countries. Ultrasound is now an accepted procedure to differentiate between arthralgia and arthritis, to look for erosions in early arthritis which is otherwise not visible on plain radiographs, to scan tendons in enthesopathies and to image blood vessels. It is particularly useful in early undifferentiated arthritis, where presence of synovitis by ultrasound can predict development of rheumatoid arthritis. It is also useful to aid in diagnosis of a wide variety of rheumatic conditions like gout, vasculitis and scleroderma. It facilitates correct placement of needle during intra-articular injections.The advantages of ultrasound are it is relatively inexpensive, noninvasive, lacks radiation and the images are acquired in real time. Following in the footsteps of the cardiologist who are using echocardiography are the rheumatologists who are increasingly using ultrasound in their clinics, such that some authors have likened the US probe to the rheumatologist's stethoscope.