US of the intrinsic and extrinsic wrist ligaments and triangular fibrocartilage complex--normal anatomy and imaging technique.

Injuries of the intrinsic and extrinsic wrist ligaments can lead to chronic wrist pain and carpal instability, while injuries of the triangular fibrocartilage complex are a frequent cause of ulnar-sided wrist pain. Currently, magnetic resonance (MR) arthrography is the preferred imaging modality for the evaluation of these structures, but good results can also achieved with MR imaging without preceding arthrography and computed tomographic (CT) arthrography. Promising results have been published on ultrasonography (US) and sonoarthrography of the intrinsic wrist ligaments and the triangular fibrocartilage complex and on US of the majority of extrinsic wrist ligaments. Visualization of these structures can be achieved by using high-frequency linear transducers. US has the advantages of MR imaging and MR arthrography: lower cost, no known contraindication for imaging, and real-time technique with possible dynamic evaluation. This technique does not require imaging guided intraarticular injection of contrast medium prior to MR arthrography or CT arthrography and does not use ionizing radiation; however, US is operator dependent, which can be compensated for by using standardized imaging techniques. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.e44/-/DC1.