Cervico-medullary Myelopathy: Compression at the foramen magnum – the bony hole at the base of the skull through which the brainstem and spinal cord exit the skull – can cause a child’s brainstem to “kink.” This can cause a child to have:

• very brisk reflexes
• numbness
• weakness
• difficulty walking
• loss of bowel and bladder control
• sleep apnea – periods during sleep when the child stops breathing.

Brainstem compression can ultimately lead to death if it is left untreated, so parents and physicians of achondroplastic children should watch for the symptoms outlined above.