Official reprint from UpToDate®
www.uptodate.com ©2016 UpToDate®

Triquetrum fractures

Kevin deWeber, MD, FAAFP, FACSM
Section Editors
Patrice Eiff, MD
Chad A Asplund, MD, FACSM, MPH
Deputy Editor
Jonathan Grayzel, MD, FAAEM


This topic will review issues related to fractures of the triquetrum. General overviews of wrist pain and carpal fractures, as well as topics devoted to other specific carpal fractures in adults, are presented separately. (See "Evaluation of the adult with acute wrist pain" and "Evaluation of the adult with subacute or chronic wrist pain" and "Overview of carpal fractures" and "Scaphoid fractures" and "Hamate fractures" and "Lunate fractures" and "Capitate fractures".)


Hand fractures are among the most common of the extremity injuries, accounting for about 18 percent of all fractures. Carpal bone fractures comprise upwards of 8 percent of hand fractures [1]. Fractures to bones of the proximal carpal row—comprising the scaphoid, lunate, triquetrum and pisiform bones—are most frequent. The triquetrum is the second most common carpal fracture after the scaphoid, representing 13 to 28 percent of all carpal bone injuries [1-4].


The triquetrum is located just distal to the ulna and the triangular fibrocartilage complex (TFCC), and proximal to the base of the hamate (image 1 and figure 1 and figure 2). The triquetrum is a small, pyramid-shaped bone that is largely covered in ligaments that connect it to surrounding structures. The triquetrum articulates with three bones: lunate, pisiform, and hamate. The lateral surface of the triquetrum is flat and articulates with the lunate, to which it is attached by the lunotriquetral ligament. The distal end faces laterally forming the sinuous, concave facet that articulates with the hamate bone. The ventromedial facet that articulates with the pisiform bone is oval shaped. The proximal end of the triquetrum forms a smooth facet for articulation with the TFCC and distal radioulnar joint. The anatomy of the wrist is discussed in greater detail separately. (See "Anatomy and basic biomechanics of the wrist".)

The triquetrum is palpable on the ulnar or dorsal aspect of the wrist just distal to the ulnar styloid and TFCC, but distinguishing it from the more distal hamate may be difficult, and the extensor carpi ulnaris (ECU) tendon may be superficial to it, further complicating palpation. Placing the wrist into radial deviation may make it more prominent and palpable.


Triquetrum fractures typically occur from a fall onto an outstretched arm with the wrist in extension and ulnar deviation, or in extreme flexion [5]. Shearing forces exerted by the proximal hamate, distal ulna, or both may play a role. In addition, either the dorsal or volar radiotriquetral ligaments may avulse triquetral fragments at their attachments.


Subscribers log in here

To continue reading this article, you must log in with your personal, hospital, or group practice subscription. For more information or to purchase a personal subscription, click below on the option that best describes you:
Literature review current through: Sep 2016. | This topic last updated: Sep 19, 2016.
The content on the UpToDate website is not intended nor recommended as a substitute for medical advice, diagnosis, or treatment. Always seek the advice of your own physician or other qualified health care professional regarding any medical questions or conditions. The use of this website is governed by the UpToDate Terms of Use ©2016 UpToDate, Inc.