Ulnar styloid process fracture and triangular fibrocartilage complex tear

Case contributed by Dr Dalia Ibrahim


Trauma to the ulnar side of wrist.

Patient Data

Age: 30 year-old
Gender: Male
  • Avulsion fracture of the tip of the ulnar styloid process with a fracture line of low signal is seen separating the avulsed bone fragment from the parent bone,marrow edema signal involves the avulsed bone fragment as well as the ulnar styloid eliciting high signal at STIR WI (this helps in differentiating fracture from styloid accessory ossicle).
  • A large central perforation of the radial portion of the triangular fibrocartilage, also increased signal within the ulnar styloid attachment of the TFCC is noted. 
  • Mild wrist joint effusion with extension of the joint effusion into the distal radio-ulnar joint.
  • The extensor carpi ulnaris tendon is mildly swollen showing subtle increased signal, denoting mild tendinopathy.
  • A small ganglion cyst is noted along the dorsal aspect of the wrist.
  • Subtle non displaced spiral fracture of the distal radial shaft reaching its articular surface.


The ulnar styloid avuslion fracture is well demonstrated on the plain X-ray showing sharp edges

Case Discussion

Avulsion fracture of ulnar styloid process.

Central perforation of the radial portion of the triangular fibrocartilage with distal radio-ulnar joint effusion.

This would classify as a Palmer Ia lesion.

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Case information

rID: 30470
Published: 13th Aug 2014
Last edited: 8th May 2019
Inclusion in quiz mode: Included

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