Pitfalls of spinal arteriovenous malformations mimicking degenerative spinal disorders

We report the case of a 64-year-old male suffering from long-term claudicatio spinalis who underwent surgery in an orthopedic outpatient ward for posterior lumbar interbody fusion and bony decompression due to spinal stenosis. Postoperatively, the clinical symptoms, consisting of difficulties with walking and stocking-like dysesthesia of both lower extremities, did not improve. Due to persistent complaints, spinal MRI was performed which revealed myelomalacia and moreover was indicative of dural arteriovenous (AV) malformation at the L2-3 spinal level, which was verified as a type la AV fistula (according to Spetzler) by digital subtraction angiography (DSA). After microsurgical treatment of the AV fistula, clinical symptoms improved and control DSA could demonstrate complete disconnection of the fistula without any signs of recanalization. This case demonstrates that neurological deficits of patients suffering from degenerative spinal disorders can generally be considered as caused by more common spinal disease such as lumbar stenosis. Since vascular malformations may also cause neurological deficits and even mimic symptoms of spinal stenosis, it is important to consider these entities in diagnostic evaluation.