Because collagen is like the glue that holds the human body together, people with EDS almost always show marked joint hypermobility, eg. "double-jointedness". In its severe form, EDS causes frequent dislocations, because there is very little holding joints in place.
Tendons, ligaments, skin and internal tissues can be amazingly stretchy, but this also creates weakness, so sufferers' skin usually bruises, cuts and scars easily, as well as being unusually sensitive to heat and sunburn. Also, because our eyes are composed predominantly of collagen, sufferers are often short-sighted and have a high risk of glaucoma later in life.
The Classical types embody all of these symptoms. Type 1 is the name given to the more chronic cases, while Type 2 refers to those with less severe symptoms.
The Classical and Hypermobile types are very similar, however the Hypermobile type has loose joints as its most chronic symptom. Skin and organ problems are less severe in this type. Building lean muscle to protect and strengthen joints can greatly improve symptoms and reduce dislocations, while still allowing for increased mobility.
In the Vascular form, EDS affects the walls of veins and arteries, making them thin and extremely fragile. The vast majority of sufferers of this type die from cardiovascular complications before the age of 50.
It is also important to note that sufferers of the other 3 types are also at risk of cardiovascular problems.
For more information, contact the Ehlers-Danlos Syndrome National Foundation (EDNF)