Ehlers-Danlos (EDS) is a set of at least 13 disorders that impact the connective tissue. The most common (and relevant to this page) is the hypermobile type. This impact the joints and creates generalised joint hypermobility that can lead to joints sub-luxing and/or dislocating. This can be very painful and lead to dysfunction in the joints.
It also impacts other areas of the body as it all contains connective tissue. Including digestion issues, skin problems, leak organs. Some types (vascular) can even be fatal in early adulthood.
EDS can cause instability in the neck leading to craniocervical instability (CCI). Both EDS and CCI can lead to very disabling symptoms that cause the patient to become bed-ridden.
It also has many associated/co-morbid conditions like Chiari, Intracranial hyper/hypotension, mast cell issues, etc.