What Is Peripheral Neuropathy?

Peripheral neuropathy is a condition that affects the peripheral nervous system, which is the vast network of nerves outside of your brain and spinal cord. These nerves connect the central nervous system to the rest of your body, enabling communication between your brain and muscles, skin, and internal organs. When you have peripheral neuropathy, this communication gets disrupted, leading to various symptoms depending on which nerves are damaged.

When Does Peripheral Neuropathy Occur?

As a physical therapist from Move Empower Concierge PT can explain, peripheral neuropathy occurs when nerves in the peripheral nervous system become damaged or diseased. These nerves serve as the body’s information highways, transmitting signals from the brain to different parts of the body and vice versa. When these pathways are disrupted, signals may be blocked, confused, or exaggerated, causing a variety of symptoms.

There are different types of peripheral neuropathy, and the symptoms can range from mild to severe. Some people may experience numbness, tingling, or a burning sensation in their hands or feet. Others may deal with sharp, stabbing pain, muscle weakness, or problems with coordination. Since these nerves control many functions in the body, peripheral neuropathy can also affect things like blood pressure, heart rate, and digestion.

To understand what happens during peripheral neuropathy, it’s essential to know a little more about the peripheral nervous system. This system includes:

• Sensory Nerves: These nerves relay information about things like temperature, pain, and touch to the brain. If these nerves are damaged, you might feel abnormal sensations like tingling or numbness, or you may lose the ability to sense pain or temperature changes.
•  Motor Nerves: These nerves control muscle movements. Damage to these nerves can lead to muscle weakness, spasms, or even difficulty walking.
•  Autonomic Nerves: These nerves manage automatic body functions, like heart rate, blood pressure, and digestion. When these nerves are affected, it can lead to problems with sweating, bowel movements, and bladder control.

Causes of Peripheral Neuropathy

Peripheral neuropathy can be caused by many different factors. Some of the most common causes include diabetes, infections, certain medications, and physical injuries. In some cases, the exact cause remains unknown, which is called idiopathic neuropathy.

Diabetes  

One of the leading causes of peripheral neuropathy is diabetes, especially when blood sugar levels are not well controlled. High blood sugar can damage the small blood vessels that supply the nerves with oxygen and nutrients. This damage, in turn, leads to nerve malfunction. Diabetic neuropathy often affects the feet and legs first, causing symptoms like numbness, burning pain, and loss of sensation. Without proper care, diabetic neuropathy can lead to serious complications, such as foot ulcers or infections.

Physical Injuries  

Any kind of physical trauma or injury can also lead to nerve damage. This can happen during car accidents, falls, or sports injuries. When a nerve is crushed, cut, or compressed for a long time, it can lose its ability to function properly. Common examples of physical trauma that cause neuropathy include broken bones, herniated discs in the spine, or repetitive strain injuries.

Infections  

Certain infections can cause inflammation of the nerves and lead to neuropathy. For example, viruses like shingles (herpes zoster), HIV, and hepatitis C can directly affect the nerves. Lyme disease, a bacterial infection transmitted by ticks, is another known cause of peripheral neuropathy. In these cases, treating the underlying infection often helps reduce or resolve the nerve damage.

Alcoholism  

Chronic alcohol use can also cause peripheral neuropathy. Alcohol is toxic to nerve tissue, and excessive consumption over time can damage the nerves, leading to neuropathy. This is often compounded by poor nutrition in people who drink heavily, as alcohol can interfere with the absorption of vitamins necessary for nerve health, like vitamin B1, B6, and B12.

Vitamin Deficiencies  

Speaking of vitamins, deficiencies in certain nutrients can play a significant role in the development of neuropathy. For instance, low levels of vitamin B12 can lead to nerve damage. This vitamin is crucial for the production of myelin, a protective sheath that covers nerves and helps them transmit signals efficiently. A lack of myelin can slow down or block nerve signals, causing symptoms of neuropathy.

Medications and Toxins  

Certain medications can have side effects that damage the peripheral nerves. Chemotherapy drugs used to treat cancer are well known for causing neuropathy, which can sometimes persist even after treatment ends. Other medications, like those used to treat HIV or high blood pressure, can also lead to nerve damage in some cases.

Exposure to toxins, such as heavy metals like lead, arsenic, and mercury, can be harmful to the nerves as well. Prolonged exposure to these substances, whether through work or environmental factors, can increase the risk of developing peripheral neuropathy.

Autoimmune Diseases  

Autoimmune diseases, where the body’s immune system mistakenly attacks its own tissues, can also cause peripheral neuropathy. Conditions like lupus, rheumatoid arthritis, and GuillainBarre syndrome can result in nerve damage as part of the body’s immune response. In these cases, the immune system targets healthy nerves, leading to inflammation and injury.

Hereditary Disorders  

Some people are born with genetic conditions that affect their peripheral nerves. CharcotMarieTooth disease, for example, is a hereditary neuropathy that affects the motor and sensory nerves. People with this condition experience progressive muscle weakness, loss of sensation, and deformities in their hands and feet.

Tumors  

Both cancerous and noncancerous tumors can press on nerves or grow within nerve tissue, leading to neuropathy. In some cases, cancers that originate in other parts of the body can spread to the nerves. Additionally, some people develop peripheral neuropathy as a result of their body’s immune response to the tumor, which is known as paraneoplastic syndrome.