Neurosensory hearing loss, ataxia, spastic paraparesis, sphincter dysfunction, somatosensory disturbances, and cognitive effects are associated with superficial siderosis of the central nervous system caused by chronic intrathecal bleeding. We describe superficial siderosis that developed more than a decade following traumatic brachial nerve root avulsion. While cerebrospinal fluid analysis indicated chronic intrathecal bleeding, angiography did not localize a specific source. Surgical intervention that included repair of a meningeal diverticulum and venous cauterization resulted in overall reduction, but not complete elimination, of central nervous system bleeding.