The nervous system is the body's communication center. The brain and spinal cord work with a network of nerves distributed throughout the body to carry information and instructions back and forth from the brain. Every conscious and unconscious action relies on this information exchange. Peripheral nerves exit the spinal cord and connect to a specific area of the body called a dermatome. Motor nerves control conscious movement, like walking. Sensory nerves carry signals back and forth, such as a pain message when the hand touches a hot stove. Autonomic nerves control ongoing and unconscious body processes, like digestion. Disease or damage to these nerves is called Peripheral Neuropathy. Communication is disrupted and messages may be stopped completely, sent incorrectly, or delayed.
Causes of Peripheral Neuropathy
Peripheral Neuropathy occurs when a nerve is damaged and no longer functions correctly. It presents with different symptoms depending on which type of nerves are affected. Causes may be apparent with rapid onset or unclear and develop over time. They can include:
- Trauma - Injury from something like a car accident, slip and fall, or sports collision damages nerves when bones displacement, swelling, and inflammation creates pressure on its fibers.
- Diabetes - High blood sugar levels damage nerves. This often presents as burning in the hands and feet or other sensation changes.
- Circulation Problems - Reduced blood flow limits oxygen delivery and damages nerves. Diabetes, smoking, high blood pressure, and atherosclerosis all limit circulation, affecting nerves.
- Auto-Immune Diseases - The body may attack its nerves due to conditions like Lupus and Rheumatoid Arthritis. It may also damage nerves when fighting an infection like Epstein-Barr or Hepatitis.
- Kidney and Liver Disease - Disorders of the kidney or liver allow the buildup of harmful toxins that damage nerves.
Medications - Some medications, including chemotherapy and radiation treatments, damage peripheral nerves. - Cancer - Tumors from cancer may invade nerves or press on fibers, damaging the nervous system.
- Vitamin Deficiency - Poor diet and nutrition or prolonged alcohol abuse deprive nerves of Vitamin B12 or cause a buildup of excessive Vitamin B6.
Signs and Symptoms of Peripheral Neuropathy
Although there are many causes and types of Peripheral Neuropathy, they present with common symptoms. Individuals, especially those with a pre-existing condition like diabetes or heart disease, must monitor for changes in sensation, motor function, and pain. Symptoms correspond to the type of nerve that is damaged. This helps doctors make their diagnoses and form a treatment plan.
- Muscle Weakness - Feelings of weakness or heaviness in the arms and legs. These symptoms may be so severe that they hinder normal movement.
- Tingling - A pins-and-needles sensation or numbness in the hands and feet. It may be persistent or intermittent. Tingling may spread into the arms or legs.
- Pain - Sharp, stabbing, or burning pain. It may feel like an electric shock.
- Changes in Sensation - Increased or decreased sensitivity to pain, pressure, heat, or cold. Patients may also experience extreme sensitivity to touch.
- Paralysis - The inability to move a body part.
- Low Blood Pressure - A drop in blood pressure that leads to lightheadedness, dizziness, or fainting.
- Excessive Sweating - A change in the amount of sweat that is unrelated to temperature or physical exertion.
- Sexual Dysfunction - Most common in men.
- Urinary or Digestive Changes - Bladder problems, changes in urination, bloating, nausea, vomiting, diarrhea, and constipation may signal a nerve problem.
- Falls or Motor Changes - A loss of coordination leading to falls or diminished motor control may result from nerve problems.
Getting Treatment
Peripheral Neuropathy can be its own condition or symptomatic of another underlying disease. Consulting with a physician when a nerve problem presents is important to prevent or treat a more serious condition. Physicians determine which type of nerves are damaged with a physical examination and review of the patient's symptoms. Nerve Studies, MRI, CT, and autonomic testing are used for diagnosis depending on the patient's presentation. If the neuropathy is caused by a disease or underlying condition, treating the disease may resolve the nerve problem. Pain medication, electrotherapy called TENS, braces or splints, physical therapy, or surgery are used to manage the condition depending on its cause and the type of nerves involved.