It is well documented that children with neurofibromatosis type 1 are at high risk for a variety of cognitive and learning deficits. The current study investigated the use of a developmental screening tool, the Parents' Evaluation of Developmental Status: Developmental Milestones, as an accurate, reliable, and efficient indicator of developmental delays. Sixty-eight percent of children with neurofibromatosis type 1 were found to have a developmental delay in at least 1 of the 8 areas tested by the Parents' Evaluation of Developmental Status: Developmental Milestones. Significant developmental abnormalities were found in the areas of fine motor (35%), gross motor (52%), and math/premath (31%). A positive association was found between the presence of a previously diagnosed optic glioma and math/premath delays (χ(2) = 0.0022) and between male sex and fine motor delays (χ(2) = 0.0325). The Parents' Evaluation of Developmental Status: Developmental Milestones assessment demonstrates the high presence of developmental delays in children with neurofibromatosis type 1 and the need for aggressive and early screening.

Previous studies have suggested that children with neurofibromatosis type 1 (NF1) are shorter than their unaffected counterparts. Unfortunately, these reports did not consider other contributing factors that might also influence short stature. The purpose of the current study was to characterize the genetic influence of NF1 on the growth of children. Height data was measured and recorded for 170 patients, while parental measurements were obtained for 61 patients to calculate sex-corrected mid-parental target heights. Children with NF1 had population mean height and mid-parental height z-scores statistically different from the general population. Importantly, these differences were pronounced when neither parent had NF1, but were not significant when one of the parents had NF1. Moreover, height z-scores for children with NF1 were also statistically different than their unaffected siblings. Collectively, these data establish a clear effect of a germline NF1 gene mutation on stature in children with NF1.

There are currently no objective criteria to evaluate pediatric hypotonia. The purpose of this pilot study was to identify diagnostic criteria for assessing hypotonia in children with Neurofibromatosis type 1 (NF1). Fifty-five subjects between the ages of 1 and 7 years with a diagnosis of NF1 were evaluated. A physical therapist recorded a subjective tone assessment and objective tone metrics, including ankle dorsiflexion, knee extension, hip abduction, triceps fat percentage, grip strength and head lag during a pull-to-sit test. Multivariate logistic regression analysis showed the presence of head lag paired with increased hip range of motion was a significant predictor of hypotonia. The presence of head lag on a pull-to-sit test paired with increased hip range of motion is an accurate predictor of hypotonia in children with NF1. These objective measures should be prospectively evaluated in other pediatric populations for their ability to predict hypotonia.