Carpal fractures and fracture dislocations
Injuries to the carpal bones fall into three major categories:

The scaphoid bone (S) bridges the proximal and distal rows of carpal bones, making it especially vulnerable to injury. Most commonly, fractures occur at the waist but may also involve the proximal or distal pole (Figure 18.33).

Figure 18.33

Perilunate dislocations occur with or without an accompanying scaphoid fracture. The lunate (L) stays in a volar position while the remaining carpal bones dislocate posteriorly (Figure 18.34).

Figure 18.34

Evaluation

The wrist appears swollen and painful to move.

::	Scaphoid fractures are tender in the anatomic snuff box and over the scaphoid tubercle on the volar aspect of the wrist. If a perilunate dislocation has occurred, these findings are diffuse about the wrist. X-rays are necessary to make a definitive diagnosis.
::	In perilunate dislocations, the lateral X-ray shows an anteriorly displaced lunate bone, with its concavity facing forward (Figure 18.34). The carpus is shortened and the proximal margin of the capitate does not articulate with the concavity of the lunate.
Figure 18.34

Treatment