Dysplasia epiphysealis hemimelica.

The historical aspects of dysplasia epiphysealis hemimelica are presented in this article along with three cases illustrating some of the problems of understanding and diagnosing a condition. A theoretical discussion of pathogenesis is attached as an example of the kind of argument often presented to Ben Felson when looking for help in understanding radiographic findings. He often indicated the directions for more work, but his knowledge, wisdom, and reasoning powers just as often hit upon a key concept that had eluded us. It is my loss that this article was not written and presented to Ben at a time when we had more available than a file of miscellaneous notes.