[Ultrasonography of the wrist and the hand].

There are six large groups of indications for sonographic study of the wrist and the hand: study of nerves, tendons, synovial cysts, ligaments and bony structures, diagnosis of Stener lesion, and search of pulley's abnormalities at the fingers. Use of high frequency probes as well as a gel-pad are required. The examination is essentially delicate, comparative and dynamic. Some structures such as small soft collections may disappear when the pressure of the probe is too heavy. An abnormality may become obvious only by comparison with the normal side, or appear only in a special position, such like synovial cysts. Recognition of osseous landmarks is essential, especially in the study of the wrist.