[Diagnostic possibilities of sonography: ankle joint, foot and Achilles tendon].

In patients with soft tissue swelling and pain of the foot and ankle, ultrasonography is a simple and reliable diagnostic procedure to demonstrate joint effusions or a tendovaginitis which may have caused the symptoms of the patient. The diagnostic puncture of a joint is only necessary to determine the kind of effusion. The diagnostic workup of patients with acute and chronic instability of the proximal ankle joint benefits from the sonographic measurement of the talus tilt and of the anterior drawer. As the diagnostic performance is equal to the radiologic stress test, X-ray exposure can be avoided. As the anatomic structure of the achilles tendon causes the typical fibrillary sonographic pattern, structural changes due to tendinitis or tendon rupture can easily be diagnosed.