Ultrasound of the ankle: anatomy of the tendons, bursae, and ligaments.

Ankle tendon and ligament disorders are commonly encountered in everyday orthopedic practice. Whereas tendons can be affected by traumatic, degenerative, and inflammatory conditions, ligaments are mostly involved by tears. Ultrasonography (US) has been accepted worldwide as an efficient, ready, dynamic, and noninvasive tool in assessing ankle tendons and ligaments. The recent technological advances in software and hardware of US equipment have improved the possibilities of US in ankle assessment, and modern equipment allows an accurate depiction of ankle structures. As with all imaging modalities, knowledge of the scanning technique and knowledge of normal US anatomy are prerequisites for a successful examination. In this article we briefly review the normal anatomy of ankle tendons and main ligaments relevant to the US examination. Then we present the routine US technique of examination for the anterior, posterolateral, posteromedial, and posterior region followed by a description of the normal US appearance of tendons, bursae, and ligaments.