Foot On Fire

“My feet are on fire,” “I’m walking on broken glass,” “This skin sore won’t heal,” These complaints are familiar to patients with diabetes, but less acknowledged is the prevalence of these symptoms among many other conditions that affects the smallest blood vessels in the body, called capillaries. These include: High blood pressure or cholesterol, smoking, cancer treatment (radiation or chemotherapy), systemic diseases (e.g. lupus, rheumatoid arthritis), etc.

Wiring of nerves in the body is not uniform. Nerves are classified into 1) voluntary motor, 2) normal sensations, 3) pain, and 4) automatic functioning (e.g. blood vessel tone, nail growth, sweating). Nerves that carry motor and normal sensations are much more resilient than those that carry pain or automatic functions. In peripheral neuropathy, pain and automatic nerves can be damaged and leave a vacuum that the brain fills with other nerves.  As a result, these nerves may fire without purpose can cause the sensations called peripheral neuropathy.

Treating these conditions is challenging since they do not respond well to typical pain medications. They can be related to a small-scale seizure disorders, where instead of affecting the entire brain, neuropathic conditions can derive from a select group of nerves in the spine.

First line therapy is to control the underlying process contributing to the nerve damage. Further treatment focuses on interrupting the uncontrolled nerve firing. Certain medications suppress the abnormal nerve cycle. As a supplement, nerve blocks can also be used to interrupt these cycles or dilate small blood vessels. Of great excitement is the potential of spinal cord stimulation (SCS). By placing an electrode outside of the spinal canal, an electrical signal interrupts the pain pathway prior to its arrival in the brain. As an added benefit, SCS increases small-vessel circulation and improves blood flow in vulnerable neuropathic regions.