Vascular malformations, rare causes of sciatic neuropathy: A case series

BACKGROUND: Sciatica is typically a clear-cut symptom complex commonly related to an impingement at the spinal nerve level. Etiologies of sciatic neuropathy outside the neural foramina are uncommon. OBJECTIVE: To describe 4 patients presenting with radiating leg pain due to sciatic nerve involvement, all with a vascular etiology. METHODS: Four patients presenting with neuropathic pain were retrospectively reviewed. Preoperative 3 Tesla magnetic resonance imaging was used to identify these lesions, which most commonly showed diffuse T2 changes with nerve enhancement upon administration of contrast. RESULTS: Exploration revealed vascular lesions. All patients went on to external and limited internal neurolysis of the involved sciatic nerve segment. Intraoperative histological study confirmed the presence of a venous angioma, an arteriovenous malformation, a venous malformation associated with Klippel-Trenaunay syndrome, and a capillary hemangioma. Follow-up demonstrated stable neurological examinations with reduction in pain at 1 year or greater. CONCLUSION: In patients with sciatic distribution symptoms and signs, after initial negative spine imaging, high-resolution imaging of the sciatic nerve itself should be undertaken to address rarer causes such as vascular abnormalities. In these cases, exploration and fascicular biopsy provided a diagnosis; external and limited internal neurolysis improved pain.