Trial Information

Effects of Physical Training on Bone and Muscle Quality, Muscle Strength, and Motor Coordination in Children With Neurofibromatosis Type 1

Disorders of the Ras pathway have significant phenotypic overlap and include Noonan
syndrome, CFC syndrome, Legius syndrome, Costello syndrome and neurofibromatosis type 1
(NF1). NF1 is one of the most common genetic disorders presenting in childhood with an
incidence of 1/3000. NF1 is associated with skeletal abnormalities such as short stature,
scoliosis, and long bone fracture with non-union. We recently reported that children with
NF1 have abnormalities of bone and muscle architecture as evidenced by decreased bone
mineral density, decreased bone strength, and low muscle mass, all of which may predispose
them to fractures and scoliosis (Stevenson et al., 2005, 2007, 2009). Our preliminary data
show that children with NF1 have poor motor coordination and muscle strength, potentially
secondary to abnormal neuromotor learning. We hypothesize that poor motor coordination and
decreased muscle strength contribute to the osteopenia in NF1. Our objective is to identify
effective and non-invasive strategies to improve motor coordination, muscle strength, and
bone and muscle architecture in children with disorders of the Ras pathway, in hopes of
decreasing fractures and improving physical activity levels. Plyometric physical training
consists of quick, high-intensity, weight-bearing movements, and is an encouraging
intervention for use in these children.