Peripheral neuropathy results from damage to the peripheral nerves located outside the brain and spinal cord, and often causes weakness, numbness, and pain, usually in the hands and feet. It can also affect other areas of the body.
Many of us have experienced severe burning, numbness, and tingling after hitting our “funny bone.” This is caused by trauma to the ulnar nerve at the elbow. Similar discomfort may be brought on by sleeping on an arm or leg in a funny position.
The peripheral nervous system sends information from the brain and spinal cord (central nervous system) to the rest of your body. The peripheral nerves also send sensory information to the central nervous system.
Peripheral neuropathy can result from painful injuries, inflammations, metabolic problems, inherited causes, and exposure to toxins. One of the most common causes is diabetes.
People with peripheral neuropathy describe pain as stabbing, burning, or tingling. In many cases, symptoms improve, especially if caused by a treatable condition. Medications can reduce peripheral neuropathy pain.
Examples of peripheral nerve disorders include:
- Guillain-Barré Syndrome: Since the polio vaccine came into widespread use, GBS has become the most common remaining cause of acute neuromuscular paralysis. An acute, ascending, and progressive neuropathy characterized by weakness, paresthesias, and hyporeflexia.
- Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)
- Polyneuropathies
- Diabetic Neuropathies: Tingling in the feet may be caused by peripheral neuropathy. Early evaluation with laboratory studies may uncover potentially treatable disease such as diabetes and vitamin B12 deficiency.
- Mononeuropathies: Isolated numbness of the hands brought on by excessive keyboard work may be identified as Carpal Tunnel Syndrome.
- Peripheral Nerve Injuries
- Amyotrophic Lateral Sclerosis (ALS): Gehrig’s disease, a disorder of the motor nerves resulting in progressive weakness of the limbs, facial and respiratory muscles, is the most serious of the neuromuscular disorders.
- Radiculopathies
- Small Fiber Neuropathies
- Occupational Neuropathies: Industrial and athletic injuries to nerves such as the stinger in football result in arm weakness and tingling.
Symptoms
Each nerve in the peripheral nervous system has a specific function, so symptoms depend on the type of nerve affected. Nerves are classified as:
- Sensory nerves receive sensory stimuli, such as heat, pain, vibration, or touch from the skin
- Motor nerves control muscle movement
- Autonomic nerves control functions such as blood pressure, heart rate, digestion, and bladder
Signs and symptoms of peripheral neuropathy include:
- Gradual onset of numbness, tingling, or chills beginning in the hands and feet, and may progress to the arms and legs
- Feeling of severe, stabbing, throbbing, or burning pain
- Severe sensitivity to touch
- Feeling of pain during activities that shouldn’t cause ache, such as foot pain when carrying weights or when placing feet under a blanket
- Lack of coordination and falling
- Muscle weakness
- Feeling as if you are wearing gloves or stockings when you are not
- Paralysis if motor nerves are affected
If autonomic nerves are affected, signs and symptoms may include:
- Inability to tolerate high heat
- Excessive sweating or inability to sweat
- Problems with bowel, bladder, and digestive function
- Changes in blood pressure causing dizziness or fainting
Peripheral neuropathy can affect one nerve (mononeuropathy), two or more nerves in different areas (mononeuropathy multiplex), or a large number of nerves (polyneuropathy). Carpal tunnel syndrome is an example of mononeuropathy. Most patients with peripheral neuropathy have polyneuropathy.
Causes
Peripheral neuropathy is not a single disease, but nerve damage resulting from a number of conditions. Health conditions that can cause peripheral neuropathy include:
- Autoimmune diseases. These include: Sjögren’s syndrome, lupus, rheumatoid arthritis, Guillain-Barré syndrome, demyelinating neuropathy, and vasculitis.
- Diabetes. More than half of people with diabetes develop some type of neuropathy.
- Infections. Some viral or bacterial infections, including Lyme disease, shingles, Epstein-Barr virus, hepatitis B and C, leprosy, diphtheria, and HIV.
- Hereditary metabolic disorders. Disorders such as Charcot-Marie-Tooth disease is a hereditary neuropathy.
- Tumors. Malignant (cancerous) and benign (non-cancerous) growths can develop from nerves or grow to compress nerves. Additionally, neuropathy can arise from certain types of cancer related to the body’s immune response. These diseases are a form of degenerative disorders called paraneoplastic syndrome.
- Bone marrow disorders. These include abnormal proteins in the blood (monoclonal gammopathy), a form of bone cancer (multiple myeloma), lymphoma, and rare amyloidosis.
- Other diseases. These include kidney disease, liver disease, connective tissue disorders, and underactive thyroid (hypothyroidism).
Other causes of neuropathy may include:
- Alcohol addiction. Poor dietary choices made by alcoholics can lead to vitamin deficiencies.
- Exposure to toxins. Toxic substances include industrial chemicals and heavy metals such as lead and mercury.
- Medications. Some medications, especially those used to treat cancer (chemotherapy), can cause peripheral neuropathy.
- Trauma or nerve pressure. Trauma, such as car accidents, falls, or sports injuries can cut or damage peripheral nerves. Nerve compression can result from wearing a splint, using crutches, or repetitive motions such as continuous typing.
- Vitamin deficiency. B vitamins — including B-1, B-6, and B-12 — and vitamin E and niacin are essential for nerve health.
In a number of cases, a specific cause cannot be identified (idiopathic).
Treatment
Treatment aims to manage the condition causing the neuropathy and relieve symptoms. At Alimran Medical Center, we may recommend any of the following treatments:
Repetitive Transcranial Magnetic Stimulation (rTMS)
Transcranial direct current stimulation (tDCS)
Steroid injection
- Trigger point injections
- Epidural steroid injections
- Electrical stimulation
- Short and long wave
- Laser therapy
- Ultrasonic therapy
- Magnetic therapy
- Exercises
Medical and Surgical Approaches
Depending on the cause, neuropathy may be relieved by medications, vitamin supplements, physical or occupational therapy, splinting, or surgery. Here’s what your doctor may recommend for treating various underlying conditions:
- Diabetes. If you have diabetes, you and your doctor can work together to keep your blood sugar level as close to normal as possible. Maintaining normal blood sugar levels helps protect your nerves.
- Vitamin deficiency. If your neuropathy is the result of a vitamin deficiency, your doctor may recommend injections of vitamin B-12 daily for a few days, then once a month. If you have pernicious anemia, you’ll need regular injections for the rest of your life, and possibly additional vitamin supplements.
- Autoimmune disorder. If caused by an inflammatory or autoimmune process, your neuropathy treatment will be aimed at modulating your immune response.
- Nerve pressure. Treatment will likely focus on adding ergonomic chairs, desks or keyboards to your home or office, changing the way you hold tools or instruments, or taking a break from certain hobbies or sports. Only in extreme cases of nerve compression will you need surgery to correct the problem.
- Toxic substances or medications. If toxins or medications are responsible for the neuropathy, it’s critical that you avoid further exposure to the toxin.
Surgery
Radiofrequency applied to either the spinal cord or directly on peripheral nerves can stop pain and unpleasant stimulation. Peripheral nerve disorders caused by tumors and traumatic and compressive conditions can sometimes be treated surgically. With regards to diabetic neuropathy, surgeons may consider placing a spinal cord stimulator if a patient has medically-refractory pain.
Neuropathy does not usually clear up unless the underlying problem is relieved or removed. Controlling a chronic condition may not eliminate your neuropathy, but it can play a key role in managing it.