What is the difference between a caudal epidural and a lumbar sympathetic block for crps (foot)?

Different procedures: Lumbar sympathetic blocks are a more common procedure to perform for CRPS. They help to temporarily silence the sympathetic nerves involved with the redness and swelling of CRPS. Caudal epidurals inject steroids around the nerves where they leave the spinal cord and are more often performed for spinal pain (arthritis and ruptured discs) than for CRPS.

Totally different: A caudal is for radicular pain due to a disc bulge. A sympathetic block is for the sympathetic pain of CRPS.