Parkes Weber syndrome: a rare cause of foot drop.

This case report describes a patient in her late 60s, previously diagnosed with Klippel-Trenaunay syndrome who presented with difficulty walking. A year prior to her presentation she had a fall which made her notice a painless foot drop on the right. Her right leg was profoundly hypertrophied compared with the left, and a port-wine stain was present on the lateral side, extending from the hip to the mid-shin. The patient's differential diagnosis based on clinical examination and investigations is discussed leading to a final diagnosis of sciatic neuropathy secondary to an arteriovenous malformation due to Parkes Weber syndrome.