Complications

These include:

• spinal stenosis, which may result in neurological impairment
• hydrocephalus - occurring in about 5% of patients, requiring treatment in 2%

Gross motor skills develop late in a child with achondroplasia. 50% of children with the condition will sit alone by 9 months and just over 50% will walk alone by 18 months. (1)

The most severe complication results from cranio-cervical stenosis and medullary and upper spinal cord compression (2)

References

1. Wright MJ, Irving MD; Clinical management of achondroplasia. Arch Dis Child. 2012 Feb;97(2):129-34.
2. Hecht JT, Bodensteiner JB, Butler IJ; Neurologic manifestations of achondroplasia. Handb Clin Neurol. 2014;119:551-63.