Pain, Tingling, Numbness: Could It Be Peripheral Neuropathy?

The magnificent human nervous system carries electrical signals from the brain to every corner of the body and back, so if something goes wrong, it could happen anywhere on that neural highway. The symptoms of the malfunction vary greatly depending on the locale, and so does the treatment.

What Is Peripheral Neuropathy?

The nervous system has two parts. The brain and spinal cord make up the central nervous system. Think of them as the control center (brain) and superhighway (spinal cord.) Everything else is the peripheral nervous system – think state highways, county roads and city streets – carrying messages between the central nervous system and every organ, system and limb, right down to your fingertips and toes. The peripheral nerves are further divided into those controlling your autonomic functions – breathing and digesting food, for example – and the sensory nerves, which carry messages to the brain about the environment – messages like “my feet are cold” or “that surface is hot.”

When something goes wrong with the peripheral nerves, the various disorders are called peripheral neuropathy, which can be felt as tingling, numbness or pain when the sensory nerves are affected, or muscle weakness, twitching and even paralysis in some cases involving autonomic nerves.

Peripheral neuropathy is not a single disease – it’s an umbrella term for any disorder that causes damage to the peripheral nervous system, whether from trauma, injury, compression, inflammation or disease. More than 100 types of peripheral neuropathy have been identified, and about 2.4 percent of the general population – more than 20 million people in the United States alone – are estimated to have some form of it. The prevalence is almost four times higher (8 percent) in people over 65.

Causes, Symptoms and Diagnosis

Common causes include diabetes, alcohol abuse, vitamin deficiency, viruses, some autoimmune diseases and chemotherapy. Sometimes the cause is never determined, in which case the diagnosis is idiopathic neuropathy.

Symptoms, which vary depending on the type of nerves involved, can be mild or severe. Even mild symptoms should be reported to your doctor because while peripheral neuropathy is rarely life-threatening, diagnosis and treatment are important to bring symptom relief, to prevent augmentation and, in some cases, to provide a cure.

To diagnose peripheral neuropathy, and the type, your doctor will conduct a complete medical and neurological examination. It likely will include blood tests, which can identify diabetes, the most common cause of peripheral neuropathy, along with vitamin deficiencies, metabolic disorders and much more. Additional tests used to diagnose peripheral neuropathies may be required, including:

• A nerve biopsy (surgical removal of some nerve cells for examination), which can show which nerve cells and cell parts are affected
• A skin biopsy (removing a small piece of skin for examination) is frequently used to diagnose small fiber neuropathies
• Electrodiagnostic techniques, including:
  • Nerve conduction velocity tests that measure the strength and speed of those electric messages to and from the central nervous system and can identify the nerves affected and the type of degeneration
  • Electromyography, which measures electrical activity by inserting tiny needles into specific muscles to evaluate the nerve-muscle communication
• Computed tomography (CT) scans and Magnetic resonance imaging (MRI, which can reveal herniated disks, tumors and other issues

Treating Peripheral Neuropathy

Your diagnosis will determine your treatment. For example, if a vitamin deficiency is the cause, vitamin replacement could bring a cure; if diabetes is the cause, controlling blood sugar could prevent further nerve damage.

Lingering pain can also be treated through various techniques, including:

• Over-the-counter oral medications for pain relief (aspirin, ibuprofen and acetaminophen, for example)
• Prescription oral medications to reduce pain, such as gabapentin
• Topical medications (creams and patches) to numb nerves
• Physical therapy to improve nerve signals to muscles
• Injected anesthetics (usually lidocaine and bupivacaine) to temporarily block certain nerve pain by interrupting pain signals
• A transcutaneous electrical nerve stimulation (TENS) device to stimulate nerve fibers to reduce pain signals to the brain
• Peripheral nerve stimulators and spinal cord stimulators, which require a surgical procedure and are a powerful way of inhibiting pain

Symptoms of peripheral neuropathy should never be ignored. Even if you are diagnosed with a form that is not fully curable, you and your doctor can find a treatment to keep it from getting worse and to manage pain.