Arachnodactyly ("spider fingers") or achromachia, is a condition in which the fingers are abnormally long and slender in comparison to the palm of the hand. It can be present at birth or develop in later life. In some cases, all or a few fingers may be bent backwards by 180 degreesThis feature can occur on its own, with no underlying health problems. However, it can also be associated with certain medical conditions. Examples include Marfan syndrome, Ehlers Danlos Syndrome,Loeys–Dietz syndrome and homocystinuria.