Forty-four children with neurofibromatosis were found to have three previously underdescribed conditions: thoracic lordoscoliosis, protrusio acetabuli, and monomelia neurofibromatosis. Thirty-four patients (77%) had scoliosis; of these, nine had dystrophic scoliosis (Group I, 26%), six had dystrophic lordoscoliosis (Group II, 18%), eight had dystrophic kyphoscoliosis (Group III, 24%), and 11 had nondystrophic scoliosis (Group IV, 32%). Group III curves were severe and progressive, rendering them difficult to stabilize even with anterior and posterior spinal fusions. Group II curves were progressive but stabilized by posterior spinal fusion alone. Group I curves were less progressive than Groups II and III, but required surgery more often than those of Group IV, which were generally controlled by orthoses. Protrusio acetabuli of varying severity occurred in 13 patients (21 hips). Three patients had involvement of a single limb (monomelic neurofibromatosis).