| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Allegheny General Hospital Pittsburgh, PA 15212
The case report by Davis et al. in the November 2004 AJR [1] reported an unusual injury to the upper thoracic spine. The authors described the injury as a Chance fracture. I am speculating that they did so on the basis of the appearance of the injury on the reconstructed sagittal and coronal CT images. However, my review of the images published as Figure 1 in the article indicates that they are not typical of a Chance-type fracture. When the remainder of the CT findings that the authors reported are taken into account, this patient appears to have suffered a rotary ("grinding") fracture dislocation. This severe injury occurs when the upper part of the torso violently rotates while the lower torso is fixed [2]. The vertebra is literally torn apart with significant fragmentation, as illustrated in Figure 1C of the article. Furthermore, there are frequently accompanying fractures of the transverse processes or ribs, which were reported in this case. In addition, the injury produces a characteristic appearance on lateral radiographs or on sagittal CT or MR images that includes a fragment of varying size resembling the top of an aluminum can that has been ripped off ("ripped can top" sign) [2]. The final pieces of evidence in this case are the perched facets that are visible in Figure 1B.
The injury illustrated in this case report frequently results from either rollover crashes, such as occurred to this patient, or from motorcyclists being thrown over the handlebars of their bikes and striking a solid object. In the latter instance, the lower torso twists as the upper torso makes contact with the solid object [3].
The fractures originally described by Chance [4] and Smith and Kaufer [5] involve horizontal fractures through the vertebral body, pedicles, transverse processes, and spinous process (Chance fracture). The Smith/Kaufer fracture does not involve the spinous process. Both of these injuries produce posterior distraction and anterior wedging but not dislocation, as is shown in this case. The Smith/Kaufer fracture, incidentally, is more common. However, because Chance's paper was published 20 years earlier, his name is associated with the injury. Because these injuries are often confused, it is preferable to refer to all horizontal fractures of the thoracolumbar region as "Chance-type" injuries. Chance-type injuries are frequently associated with severe intraabdominal injuries. However, they rarely produce neurologic findings because the vertebral canal is decompressed by the distraction. Rotary injuries, on the other hand, almost always result in severe neurologic deficits, as occurred in the case presented.
 Top References |
|---|
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  B. Thonar, N. H. Patel, H. Ferral, and G. Behrens AJR Teaching File: Chest Pain in a Woman with an Inferior Vena Cava Filter Am. J. Roentgenol., September 1, 2007; 189(3_Supplement): S24 - S25. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
