Nerves carry instructions from the brain throughout the body, and send information back from the body to the brain. Sensory nerves enable the body to see, hear, taste and feel, while motor nerves help muscles move and organs function. Nerve pain is a distress call to the brain from the body, alerting the person to the possibility that they are being physically damaged.
Pressure
Tumors, aneurysm, or any other force that compresses a nerve can result in pain. Genitofemoral neuralgia manifests as pain in the testicles, or outer part of the upper thigh. It commonly occurs due to post surgical nerve entrapment after a patient has undergone an appendectomy or hernia repair, according to Stanley Weiner in the book, "Clinical Methods: The History, Physical and Laboratory Examinations".
Compression of the third cranial nerve, or oculomotor nerve, can result because of an aneurysm or tumor, causing headache or eye pain, according to MedlinePlus.
Trauma
Trauma due to motor vehicle accidents, falls or violence can damage nerves resulting in pain. The sciatic nerve is the body’s longest nerve, extending from the lower spin across the buttocks and down the back of the legs. MedlinePlus states that it can frequently become injured in cases of pelvic fracture, leading to pain along the nerve that can range from mild to excruciating.
Infection
Some types of infection will cause nerve pain. Anne Mounsey, M.D, of the University of Virginia, states that shingles occurs when the dormant herpes zoster virus, which causes chickenpox, reactivates, most often decades after the virus was originally contracted. The shingles virus resides asymptomatically within nerve bundles for many years, then becomes active again and begins traveling along the nerves, causing pain.
Other infectious diseases commonly resulting in nerve pain include Lyme disease, herpes simplex and syphilis.
Systemic Disease
A number of systemic diseases can cause damage to the nervous system resulting in nerve pain. Chronic renal insufficiency is a kidney disease that can cause peripheral nerve damage. The National Kidney Foundation explains that this can result in symptoms such as pain or numbness in the hands, legs and feet, or a burning sensation in the feet.
Diabetes can negatively impact the nerves as well. The oculomotor nerve is often affected by diabetes, according to MedlinePlus.
Another cranial nerve, the trigeminal nerve, can become damaged by diabetes and also by multiple sclerosis. The trigeminal nerve detects sensation across most of the face and trigeminal neuralgia results in short shocking bursts of facial pain.
Toxic Chemical Exposure
A number of toxic chemicals can cause nerve pain. The United States Department of Health and Human Services warns that polychlorinated biphenyls, or PCBs can cause neuralgia in the limbs. PCBs were commonly used as coolants and lubricants, but their manufacture ceased in 1977 in the U.S., due to environmental concerns.
Dioxins are a toxic byproduct of PCB manufacturing, and are chemicals used in herbicides, germicides and bleach, have also been noted to cause neuralgia, as well as a host of other health conditions, according to the Illinois Department of Public Health.
