Spinal Intraosseous Epidural Arteriovenous Fistula; A Late Complication of Vertebral Compression Fracture: Two Case Reports

Introduction: Spinal epidural arteriovenous fistulas (SEDAVFs) are extremely rare and the pathological process still remains unclear. Nevertheless, neurofibromatosis, surgery, as well as trauma have been implicated as causes. Nevertheless, long standing chronic vertebral compression fractures (VCFs) as a cause of SEDAVFs has not been reported in literature. Case Presentation: Our cases comprised of a male and female with ages 67 and 62 year respectively. They presented with weakness of bilateral lower extremities and back pain. Their symptoms deteriorated into mild recto-bladder dysfunction as well as hypoesthesia of lower limbs. They both had history of road traffic accidents (RTAs) prior to their symptomatology. In both cases, Magnetic resonance imaging (MRI) revealed VCFs prior to the above symptomatology. Spinal digital subtraction angiography (DSA) was used to confirm SEDAVFs in both cases. We utilized the trans-arterial route with Onyx embolization agent to obliterate both fistulae and their symptom resolved after the embolization. Two-years follow-ups revealed no recurrence of their fistulae. Conclusion: The initial long standing VCFs caused by trauma resulted in perforation of the dorsal somatic branches of the radicular artery leading to the occurrences of SEDAVFs in our cases.