A special feature of these two cases of painful non-suppurative, non-inflammatory cortical thickening of the long bones is that the radiolucent area is not sharply outlined; in this it resembles the illustrative roentgenograms of Jaffe and Lichtenstein, and of others.
On microscopic examination, the bone focus removed in the second case resembled the histological description given by Jaffe and Lichtenstein.
No positive opinion is expressed regarding the essential nature and cause of the bone lesion in the two cases.