Occasionally, the source of foot pain is purely nerve-related and is caused either by direct irritation of a nerve, or by health conditions that lead to nerve damage. When nerves are irritated or damaged, there is a characteristic burning, shooting, or stabbing pain that occurs. The pain will often occur spontaneously, even while at rest. Sometimes the area over the affected nerve may be very sensitive to the touch.
Common Nerve Problems That Cause Foot Pain
- Morton's Neuroma: A Morton's neuroma is a benign thickening of the nerve that runs between the third and fourth toes (photo). Typical symptoms include a burning or shooting pain in the area between the third and fourth toes, most often with walking. Another common symptom is a vague feeling of pressure beneath the toes, as if a sock was bunched-up underneath them. A Morton's neuroma occurs more frequently in women, possibly because of the frequency of narrow or high-heeled shoe wear. Common treatments include shoe modifications, arch supports, and cortisone injections to decrease nerve inflammation.
- Pinched Nerve: Also known as nerve entrapment, a pinched nerve can occur at various regions of the foot. A nerve entrapment is frequently caused by trauma, such as pressure created by swelling, excess pressure from a tight shoe, or blunt trauma. Nerve entrapment may cause shooting, burning pain or sensitivity on the top of the foot. Nerve entrapment on the top of the foot may be due to excess pressure on the nerve from a tight shoe.
Another common type of nerve entrapment is tarsal tunnel syndrome. Tarsal tunnel syndrome is an entrapment of the posterior tibial nerve as it descends under the inside (medial) ankle area and enters the foot through an anatomical landmark known as the tarsal tunnel. The burning, tingling sensations, or shooting pain, can radiate from the instep (arch) and heel areas into the soles of the feet. Numbness and foot cramping can also occur and symptoms can intensify at night while resting or sleeping. Treatment of tarsal tunnel syndrome usually begins with identifying and alleviating the cause, which can be anything from a problem with foot function such as flat feet to ankle swelling.
Cortisone shots and anti-inflammatory drugs may be prescribed to treat tarsal tunnel syndrome and other types of nerve entrapments. Examples of other types of conservative treatments include: padding the shoe in areas where the foot is being compressed (often at the top of the shoe) or orthotics to correct the abnormal foot structure or function causing the nerve irritation. If conservative measures fail, surgery may be required to release the nerve.
- Diabetic Peripheral Neuropathy: The chronic high blood sugar (glucose) associated with diabetes can lead to a form of nerve damage known as peripheral neuropathy. It is estimated that one in four diabetics will experience painful neuropathy. Like other forms of nerve damage, neuropathy pain is characterized by spontaneous burning or shooting pain in the feet. It often occurs at night while sleeping. The pain of neuropathy may come and go over the course of the disease and may be accompanied by a gradual loss of feeling in the feet that begins in the toes and progresses upward.
Treatments for diabetic neuropathy include blood sugar control, medications such as antidepressants or anti-seizure drugs, and vitamin supplements such as B vitamins and alpha lipoic acid.
- Other Causes of Painful Neuropathy: Damage to nerves and the resulting pain symptoms can occur with many other conditions. Some examples include:
- Physical trauma, such as after surgery or an accident
- Drugs such as certain cancer drugs, antiviral drugs, or antibiotics
- Complex Regional Pain Syndrome
- Tumors that compress a nerve
- Liver or kidney disease
- Vitamin deficiencies
- A herniated disc in the lumbar spine
- Infectious diseases such as complications from Lyme disease or viral infections
Hovaguimian MD, Alexandra and Gibbons MD, MMSc, Christopher H. "Clinical Approach to the Treatment of Painful Diabetic Neuropathy". Therapeutic Advances in Endocrinology and Metabolism. 2011;2(1):27-38