progressive scoliosis

Hypotonia may be noted at birth but ankle clonus and spasticity can develop later.  Progressive kyphoscoliosis has been diagnosed as early as the age of 4 years and may result in restrictive lung disease requiring spine surgery by the second decade of life.  Developmental milestones such as walking and talking are delayed and intellectual development is subnormal.  Mirror movements may be present.  Gait may be unsteady but can be normal.

Brain MRI reveals a variety of malformations.  Agenesis of the corpus callosum is present and the white matter tracts appear disorganized.  The superior cerebellar peduncles fail to decussate and transverse pontine fibers may be absent.  The pons and midbrain are hypoplastic while there is a midline cleft throughout the brainstem resulting in a butterfly-shaped medulla.