Radiology Teaching Files > Case 5149256

Contributed by: Radiology Residency Program Faculty & Staff.
Patient: 21 year old male
History: 21 y/o male with pain following fall

Fig. 1: Chip fracture of the dorsal triquetrum is seen on the oblique and lateral views with soft tissue edema
Findings: Chip fracture best visualized on the lateral and oblique views with adjacent soft tissue edema. Negative ulnar variance is incidentally noted.
Diagnosis: Triquetrum Fracture

-A chip fracture which is only visualized on the lateral view is almost always a triquetrum fracture
-The triquetrum is the second most commonly fractured carpal bone
-The dorsal chip fracture of the triquetrum is much more common than the triquetrum body fracture
-Multiple mechanisms for the fracture have been proposed including 
       -Avulsion from the insertion of the radioulnar ligament
       -Impaction fracture from the ulnar styloid on an ulnar deviated outstretched hand
       -Fall on a flexed hand with direct impact injury to the dorsal triquetrum
-A rich vascular supply greatly reduces the risk of AVN which is rare in the triquetrum
-Treatment is immobilization until the fracture heals or until a separate well-corticated ossicle forms. Either way, the outcome is usually satisfactory.       


1.) Weissleder R, Wittenberg J, Harisinghani MG.  Primer of Diagnostic Imaging. Philadelphia: Mosby, 2003.
2.) Brant, W and Helms, C. Fundamentals of diagnostic radiology Lippincott, 1999.

3.) Schubert, H. Emergency Case: Triquetrum Fracture. Canadian Family Physician. Vol. 46; January 2000, 70-71.

Submitted by Craig Johnson, DO PGY-4 Radiology Resident

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Additional Details:

Case Number: 5149256Last Updated: 07-02-2006
Anatomy: Skeletal System   Pathology: Trauma
Modality: Conventional RadiographExam Date: Access Level: Readable by all users

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