What is the hallmark symptom of Chiari malformation in children?

Chiari malformation is a condition where brain tissue extends into the spinal canal, which can cause a variety of symptoms due to the crowding at the base of the skull and potential obstruction of cerebrospinal fluid. The hallmark symptom in children is headaches, often described as occurring with neck strain or during physical activity. These headaches can be chronic and are typically characterized as being worsened by activities that increase intracranial pressure, such as coughing, sneezing, or straining.

Additionally, headaches in the context of Chiari malformation frequently reflect issues related to the herniation of cerebellar tissue, which may exacerbate symptoms due to its impact on the surrounding structures in the brain and spinal cord. While other symptoms like seizures, spasticity, and visual disturbances can occur in connection with Chiari malformation or secondary complications, headaches remain the most commonly reported and distinctive symptom associated with the condition in pediatric patients.