FRAGILE BONE SYNDROME-ASSOCIATED WITH CRANIOGNATHIC FIBROOSSEOUS LESIONS AND ABNORMAL MODELING OF THE TUBULAR BONES - REPORT OF 2 CASES ANDREVIEW OF THE LITERATURE

Objective. To report examples of disorders characterized by bone fragi lity, calvarial and/or gnathic fibro-osseous lesions, and metadiaphyse al undermodeling of the tubular bones. Design. The clinical, radiologi cal, and pathological features of two patients are described and the l iterature reviewed. Patients. The patients comprised a 10-year-old boy and a 48-year-old woman. The former: exhibited multiple fractures sta rting in early childhood and calvarial masses which developed in late childhood; the latter showed a mandibular mass. Results. Calvarial dou ghnut lesions, osteopenia with coarse bony trabeculae, and undermodeli ng of the lower limbs were radiologically demonstrated in the first pa tient, while multiple sclerotic foci in the maxilla and mandible, spon taneous bowing of the right femur, and minimal undermodeling of the ti biae were demonstrated in the second. Bone biopsy of the iliac crest i n the first patient revealed histologically normal bony trabeculae. Bo ne histomorphometry suggested an increased osteoid surface. Osteoid vo lume was also slightly increased. The pathological findings of the mas s in the jaw in the latter patient were consistent with it being a fib ro-osseous lesion. The literature review revealed several patients who se features overlapped with those of our patients. Conclusion. These p atients may represent a group of fragile bone syndromes which differ f rom osteogenesis imperfecta.