Dislocation of the semilunar carpal bone is not likely to occur often enough to be of much moment to physicians generally, but the fact that it may occur in almost any severe wrist injury makes recognition of this lesion imperative. The American literature in the last few years contains comparatively few reports of cases of semilunar carpal bone dislocation. The European literature, especially the German, is replete with references to semilunar carpal bone dislocations, but no great number of cases have been studied. I am unwilling to believe, however, that this lesion is as infrequent as these reports would seem to indicate.
That this particular injury does occur more often than formerly may be due to the great number of accidents caused by the backfire of gas engines, which is a common factor in producing wrist injuries. The present universal use of the roentgen ray in the diagnosis of wrist