Ehlers-Danlos syndrome (EDS)

What it is

Ehlers-Danlos syndrome (EDS) is a group of inherited connective-tissue disorders characterized by features such as joint hypermobility, skin changes, and tissue fragility. It can be associated with Chiari malformation and with related conditions such as craniocervical instability.

Understanding Ehlers-Danlos syndrome (EDS)

EDS involves alterations in connective tissue (including collagen), leading to lax, hypermobile joints and ligaments. At the craniocervical junction, this ligamentous laxity can contribute to instability and may be associated with tonsillar descent and Chiari-like findings — and the connection between EDS and Chiari (and related conditions like craniocervical and atlantoaxial instability) is increasingly recognized. For someone with both EDS and Chiari, extra testing and precautions are often taken to assess the stability of the connection between the skull and spine, because instability can affect symptoms and treatment (sometimes requiring fusion in addition to or instead of decompression). Understanding EDS and Chiari clarifies an important association that influences evaluation and management.

Why it matters

Understanding the EDS-Chiari association helps families and patients see why connective-tissue laxity can relate to Chiari and craniocervical instability, and why extra evaluation of craniocervical stability is often warranted when both are present.