Case 314 Answer

Does the lunate articulate normally with the distal radius? YES

Does the capitate articulate normally with the lunate? NO

So the lunate is NOT dislocated and this is a PERILUNATE dislocation

reference:http://www.learningradiology.com/notes/bonenotes/perilunatedislocatepage.htm

Notice the stages of carpal dislocation based upon ligament injury/severity. The perilunate is less severe (Stage 3) than a lunate dislocation (Stage 4).

And always look for an associated scaphoid fx.