Imaging Case of the Week 111

These wrist x-rays are from a 45 year old with left wrist swelling and pain who sustained the injury in a motor vehicle accident. What can you observe in the x-rays?

Left wrist x-ray AP

Left wrist x-ray lateral


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The wrist x-rays show a mildly displaced intra-articular radial styloid fracture. There is a second injury in the form of widening of the scapholunate distance (approximately 4 mm) which is suggestive of a scapholunate ligament disruption.


wrist x-ray


The intra-articular radial styloid fracture is also known as Chauffeur’s or Hutchinson’s fracture. Mechanism of injury can be a direct blow to the radial styloid or falling backward on the outstretched hand with ulnar deviation.

It is often associated with carpal bone and ligamentous injuries. Scapholunate dissociation is one such associated injury which causes widening of the distance between the scaphoid and the lunate. The normal gap is less than 2 mm; between 2 to 4 mm suggests scapholunate disruption, and a gap greater than 4 mm is indicative of scapholunate dissociation (this is known as the Terry Thomas sign).

Radial styloid fractures usually require surgical repair.

Scapholunate injuries, if undiagnosed and untreated, can lead to wrist instability.

Reference: Grainger and Allison’s Diagnostic Radiology