Polydactyly in neurofibromatosis type I: a potential clue to diagnosis

Neurofibromatosis type 1 is a genetic disorder characterized by variable phenotypic manifestations. The diagnostic criteria, 25 established in 1987, are broad to encompass these pleiotropic findings. Included are the specific osseous manifestations of 26 sphenoid dysplasia and dysplasia or thinning of the cortex of long bones. This review highlights recent evidence on the role of 27 neurofibromin in bone development and suggests consideration for additional diagnostic criteria.