125 eosinophilic granulomas of the bone in 61 cases were reported. The radiologic manifestations may be summarized as follows: (1) Multiple lesions may occur with vertebra plana; (2) Epiphyseal lesion may be primary or secondarily involved by extension from metaphyseal lesion; (3) Metaphyseal lesion usually presents as an eccentric cystic area or central oval area of lucency; (4) The diaphyseal lesion manifests a "hole within hole" appearance; (5) The tarsal bone may exhibit a "bone within bone" sign; (6) Periosteal Codman triangle may be present.