Abstract
1. One hundred and forty-nine cases of leontiasis ossea reported in the literature have been reviewed.
2. The clinical, radiographic and pathological features of the condition are discussed.
3. Four additional personal cases are reported in detail.
4. A new classification of leontiasis ossea is suggested, by which the condition is divided into true leontiasis and false (or symptomatic) leontiasis, True leontiasis is a clinical syndrome caused by two distinct types of disease, whose pathology, however, is related. False leontiasis gives a superficially similar picture but on detailed examination is found to be distinct; it may be caused by a variety of different conditions.
5. Classified in this way, ninety-seven of the total of 153 cases considered were classified as true leontiasis (forty-five Type 1 and fifty-two Type 2); forty were classified as false leontiasis; and sixteen did not fall into either category.
