Background and indications: Ultrasonography has proven valuable in evaluating inflammatory arthropathies, joint effusion, tendinopathy, and the ligaments of the wrist as well as the triangular fibrocartilage complex, (TFCC). Detailed techniques of ultrasound examinations of the intrinsic and extrinsic ligaments and the TFCC at the ulnar triquetral joint has been described.¹ The ulnar triquetral region of the wrist is both anatomically and biomechanically complex, and pain overlying this region should be carefully evaluated to elicit a specific diagnosis. For example, an excessively long ulnar styloid can impinge upon TFCC.² Anatomically, the tip of the ulnar styloid is covered by a meniscus homologue. Injuries are a common cause of ulnar-sided wrist pain and can frequently lead to functional disability. Before considering injections in this region of the wrist, one should consider carefully a target tissue or diagnosis and the most appropriate treatment.

Anatomy: The intrinsic ligaments are situated entirely within the carpus, between the carpal bones. The ligaments are divided into two major categories, namely, the intraosseous ligaments, which lie between the carpal bones, and the intrinsic capsular ligaments attaching to the carpal bones. In addition, there are two other imporTant intraosseous ligaments proximally, which is the scapholunate ligament (SLL) and the lunotriquetral ligament (LTL) (Fig. 66.1