In a few people whose burning sensation is sudden, rapidly worsening, or has no explainable cause, these tests may be needed:
- Electromyography (EMG). This test records electrical activity inside the muscles. A probe may be placed on the skin, or a needle may be inserted into the muscle, for an EMG test.
- Nerve conduction study. This tests the ability of nerves to transmit impulses.
- Lab tests. Sometimes, doctors test blood, urine, or spinal fluid to help diagnose the cause of burning feet. Vitamin levels can be checked with a simple blood test.
- Nerve biopsy. Very rarely, a doctor may suggest cutting out a piece of nerve tissue and examining it under a microscope.