Onset between 20 and 60 years of age (usually a
male who is older than 50 years). Progressive paraplegia (manifested as
increasing weakness and numbness or tingling in the lower extremities,
frequent falls), urinary and fecal incontinence, and nonradiating lower back
pain. Affected patients initially are spastic but eventually develop flaccid
paralysis of the limbs and may become wheelchair bound. Four different types
of arteriovenous malformation have been described: dural arteriovenous
fistulas, glomus malformations, juvenile type arteriovenous malformations,
and intradural extramedullary arteriovenous fistulas.