An unusual cause of progressive medullary compression

Abstract

Background: Arteriovenous malformation (AVM) of the spinal cord are rare entities, with the dural AV-fistel the most common and well-studied form. Paraspinal AVM is an extremely rare condition, with their nidus lying exclusively extradural. Although most cases present as spontaneous epidural hemorrhage with acute onset of symptoms due to spinal cord compression, unruptured paraspinal AVMs may be asymptomatic or present with progressive neurological decline due to either medullary compression by ectatic epidural veins, medullary ischemia due to venous congestion, or a combination of both. Observation: In this article we report a case of an intraosseous AVM of the thoracic spine with epidural extension, mimicking a neoplastic lesion compressing the spinal cord, causing progressive paraparesis. The patient underwent prompt surgical decompression and resection via laminectomy. The peri and postoperative course were uneventful, and there was complete neurological recovery. Conclusion: Paraspinal AVMs may present as solid tumors, compressing the spinal cord. The aim of this article was to increase awareness of this rare entity in the differential diagnosis of spinal tumors, attributing to patient’s standard of care and safety. Post-treatment functional prognosis seems good, especially in comparison with an intradural/intramedullary allocation, but delayed diagnosis and treatment may leave the patient with residual neurological deficit.

Keywords

• paraspinal AVM
• Intraosseous AVM
• Progressive myelopathy