Spinal pial arteriovenous fistulas (spAVFs) are believed to be congenital lesions, and the development of a de novo spAVF has not been previously described. A 49-year-old female with a childhood history of vascular malformation–induced right lower-extremity hypertrophy presented in 2004 with progressive pain in her right posterior thigh and outer foot. Workup revealed 3 separate type IV spAVFs, which were treated by combined embolization and resection, with final conventional angiography showing no residual spinal vascular lesion in 2005. Ten years later, the patient returned with new right lower-extremity weakness, perineal pain, and left plantar foot numbness. Repeat spinal angiography demonstrated 2 de novo intertwined conus medullaris spAVFs.