Legacy and current understanding of the often-misunderstood Foix-Alajouanine syndrome. Historical vignette.

Foix-Alajouanine syndrome has become a well-known entity since its initial report in 1926. The traditional understanding of this clinical syndrome is as a progressive spinal cord venous thrombosis related to a spinal vascular lesion, resulting in necrotic myelopathy. However, spinal venous thrombosis is extremely rare and not a feature of any common spinal vascular syndrome. A translation and review of the original 42-page French report revealed 2 young men who had presented with progressive and unrelenting myelopathy ultimately leading to their deaths. Pathological analysis demonstrated endomesovasculitis of unknown origin, including vessel wall thickening without evidence of luminal narrowing, obliteration of cord vessels, or thrombosis. Foix and Alajouanine also excluded the presence of intramedullary arteriovenous malformations. At the time, dural arteriovenous fistulas (dAVFs) had not been described, and therefore this type of lesion was not specifically sought. In retrospect, it seems possible that both patients had progressive myelopathy due to Type I dAVFs. In the decades since that original report, numerous authors have included spinal cord venous thrombosis as a central feature of Foix-Alajouanine syndrome. The inclusion of thrombosis in the clinical picture of this syndrome is not only incorrect but may leave one with the impression of therapeutic futility, thus possibly preventing successful surgical or endovascular therapy.