Inclusive Anatomy
Structure:
The dorsal tubercle of the radius is a palpable bony prominence located on the dorsal surface of the distal radius at the level of the wrist.[1] It exhibits considerable anatomical variation in size and morphology. Reported measurements indicate a height ranging from approximately 2 to 6 mm and a length between 6 and 26 mm.[1,2]
The tubercle lies between the grooves for the extensor tendons and serves as an important surface landmark on the dorsum of the wrist.[1]
Function:
The dorsal tubercle of the radius functions as a pulley for the tendon of the extensor pollicis longus, which changes direction by approximately 45 degrees as it courses around the medial aspect of the tubercle toward the thumb.[2]
Popular
Recipes
This mechanical redirection optimizes tendon leverage during thumb extension.
Because of its consistent location, the dorsal tubercle serves as a valuable anatomical landmark in wrist arthroscopy and other surgical procedures involving the dorsal wrist.[2] Hyperextension injuries or fractures involving the dorsal tubercle may increase mechanical stress on the extensor pollicis longus tendon, potentially leading to tendon irritation or delayed rupture.[2,3]
References:
-
Moore KL, Dalley AF, Agur AMR. Clinically Oriented Anatomy. 6th ed. International ed. Lippincott Williams & Wilkins; 2010.
-
Chan WY, Chong LR. Anatomical variants of Lister’s tubercle: A new morphological classification based on magnetic resonance imaging. Korean J Radiol. 2017;18(6):957-963. doi:10.3348/kjr.2017.18.6.957
-
Stahl S, Wolff TW. Delayed rupture of the extensor pollicis longus tendon after nonunion of a fracture of the dorsal radial tubercle. J Hand Surg. 1988;13(3):338-341. doi:10.1016/S0363-5023(88)80004-2
We strive to ensure the accuracy of all content. If you notice any errors or have suggestions for improvement, please reach out to us so we can review and update the material accordingly.