Pain

What is pain?

Pain is a signal in your nervous system that something may be wrong. It is an unpleasant feeling, such as a prick, tingle, sting, burn, or ache. Each person feels pain differently, even if the reason for the pain is the same. Pain may be sharp or dull. It may be mild or severe. Pain may come and go, or it may be constant. You may feel pain in one area of your body, such as your back, abdomen, chest, or pelvis, or you may feel it all over.

Pain can help alert you that there is a problem. If you never felt pain, you might seriously hurt yourself without knowing it, or you might not realize you have a medical problem that needs treatment. Finding out what's causing your pain will help your health care provider determine the best way to manage or treat it.

Patterns and types of pain are named based on how long and how often you have pain. These include:

• Acute pain usually happens suddenly because of a disease, injury, or inflammation (irritation, redness, and/or swelling). This type of pain is often sharp and acts as a warning that something is wrong. It usually goes away when the cause is treated or healed, though sometimes it can turn into chronic pain. Some examples of causes of acute pain include broken bones or dental issues.
• Chronic pain lasts for longer than three months or the time in which you should have healed. It can affect all aspects of daily life, including your mood and relationships. Some conditions that might cause chronic pain include arthritis or back problems.
• Episodic pain can happen from time to time and may occur with long-term medical conditions. Some conditions that might cause episodic pain include sickle cell disease or chronic migraines.

Pain may also be categorized by what is likely to be the cause of the pain. Pain may be described as nociceptive (caused by tissue damage or inflammation), neuropathic (caused by nerve damage), or nociplastic (caused by changes in how your nervous system processes pain).

Understanding what causes pain and why people feel it differently may be difficult. Often, it's easier to find the cause of acute pain due to an injury than the cause of chronic pain, or you may have an ongoing cause of pain, such as cancer.

In some cases, there is no clear cause. Environmental factors and psychological factors such as stress and beliefs about pain may affect the way you feel pain and respond to treatment.

You are the only one who knows how your pain feels. Your provider can best measure your pain by how you report it. They may ask you:

• Where is the pain in your body?
• How long have you had the pain?
• How does the pain feel, such as stinging, burning, or sharp?
• How often do you have pain?
• When do you feel pain, such as in the morning, evening, or all the time?
• What relieves the pain?
• How does pain affect your daily life?
• Is the pain mild, moderate, or severe?
• To rate the pain on a scale.

If the cause of your pain is unknown, your provider may also do a physical exam and order blood tests or other medical tests to help find the cause.

Pain is not always curable, but there are many ways to manage and treat it. Treatment depends on the cause and type of pain. Treatments may include medicines, such as pain relievers. There are also non-drug treatments, such as acupuncture, physical therapy, and sometimes surgery.

Depending on the cause of your pain and your symptoms, your provider may recommend lifestyle changes. These may include suggestions for:

• Eating a healthy diet
• Adding exercise
• Losing weight
• Managing stress
• Improving mental health

NIH: National Institute of Neurological Disorders and Stroke

Paralysis

Paralysis is the loss of muscle function in part of your body. It happens when something goes wrong with the way messages pass between your brain and muscles. Paralysis can be complete or partial. It can occur on one or both sides of your body. It can also occur in just one area, or it can be widespread. Paralysis of the lower half of your body, including both legs, is called paraplegia. Paralysis of the arms and legs is quadriplegia.

Most paralysis is due to strokes or injuries such as spinal cord injury or a broken neck. Other causes of paralysis include:

• Nerve diseases such as amyotrophic lateral sclerosis
• Autoimmune diseases such as Guillain-Barre syndrome
• Bell's palsy, which affects muscles in the face

Polio used to be a cause of paralysis, but polio no longer occurs in the U.S.

Parkinson's Disease

Parkinson's disease (PD) is a type of movement disorder. It happens when nerve cells in the brain don't produce enough of a brain chemical called dopamine. Sometimes it is genetic, but most cases do not seem to run in families. Exposure to chemicals in the environment might play a role.

Symptoms begin gradually, often on one side of the body. Later they affect both sides. They include:

• Trembling of hands, arms, legs, jaw and face
• Stiffness of the arms, legs and trunk
• Slowness of movement
• Poor balance and coordination

As symptoms get worse, people with the disease may have trouble walking, talking, or doing simple tasks. They may also have problems such as depression, sleep problems, or trouble chewing, swallowing, or speaking.

There is no specific test for PD, so it can be difficult to diagnose. Doctors use a medical history and a neurological examination to diagnose it.

PD usually begins around age 60, but it can start earlier. It is more common in men than in women. There is no cure for PD. A variety of medicines sometimes help symptoms dramatically. Surgery and deep brain stimulation (DBS) can help severe cases. With DBS, electrodes are surgically implanted in the brain. They send electrical pulses to stimulate the parts of the brain that control movement.

NIH: National Institute of Neurological Disorders and Stroke

Peripheral Arterial Disease

Peripheral arterial disease (PAD) happens when there is a narrowing of the blood vessels outside of your heart. The cause of PAD is atherosclerosis. This happens when plaque builds up on the walls of the arteries that supply blood to the arms and legs. Plaque is a substance made up of fat and cholesterol. It causes the arteries to narrow or become blocked. This can reduce or stop blood flow, usually to the legs. If severe enough, blocked blood flow can cause tissue death and can sometimes lead to amputation of the foot or leg.

The main risk factor for PAD is smoking. Other risk factors include older age and diseases like diabetes, high blood cholesterol, high blood pressure, heart disease, and stroke.

Many people who have PAD don't have any symptoms. If you have symptoms, they may include:

• Pain, numbness, achiness, or heaviness in the leg muscles. This happens when walking or climbing stairs.
• Weak or absent pulses in the legs or feet
• Sores or wounds on the toes, feet, or legs that heal slowly, poorly, or not at all
• A pale or bluish color to the skin
• A lower temperature in one leg than the other leg
• Poor nail growth on the toes and decreased hair growth on the legs
• Erectile dysfunction, especially among men who have diabetes

PAD can increase your risk of heart attack, stroke, and transient ischemic attack.

Doctors diagnose PAD with a physical exam and heart and imaging tests. Treatments include lifestyle changes, medicines, and sometimes surgery. Lifestyle changes include dietary changes, exercise, and efforts to lower high cholesterol levels and high blood pressure.

NIH: National Heart, Lung, and Blood Institute

Peripheral Nerve Disorders

What are peripheral nerves?

Nerves are like wires that carry messages back and forth between your brain and your body. Your peripheral nerves branch off from your brain and spinal cord and connect to all parts of your body, including your muscles and organs. Peripheral nerves carry messages from your brain that control your movement, breathing, heartbeat, digestion, and more. They also carry messages from your body to your brain, so you can feel things, such as pain, heat, and cold.

Peripheral nerve disorders happen when one or more peripheral nerves are damaged. Damaged nerves may not carry messages correctly, or they may not work at all. As a result, you may have pain, trouble walking, or a variety of other problems, depending on which nerves are involved.

Peripheral nerve disorders are very common. There are more than 100 different types.

Many things can damage nerves and lead to peripheral nerve disorders:

• Diabetes is the most common cause of peripheral nerve disorders. Most people with diabetes will develop diabetic nerve problems.
• Physical injury (trauma) that stretches, crushes, squeezes, cuts, or puts pressure on one or more nerves. Some examples of peripheral nerve disorders from physical injury include complex regional pain syndrome and brachial plexus injuries.
• Health conditions, including:
  • Certain cancers and their treatment (chemotherapy and radiation therapy).
  • Infections, such as HIV and Lyme disease.
  • Problems with blood or blood vessels.
  • Autoimmune diseases, such as rheumatoid arthritis and lupus.
  • Kidney or liver disease.
• Certain medicines.
• Contact with certain toxic substances, such as lead or mercury.
• Alcohol use disorder (AUD) and smoking.
• Vitamin imbalances, especially a lack of vitamin B12.
• Your genes, including changes in your genes or conditions that you inherit from your parents, such as Charcot-Marie-Tooth disease.

In certain cases, the cause of peripheral nerve disorder is not known.

The symptoms of peripheral nerve disorders depend on which nerves are affected, what is causing the damage, and how serious it is:

• Weak or aching muscles
• Problems with balance, walking, or using your arms and hands
• Cramps or twitching muscles
• Muscle shrinking

• Tingling, numbness, or pain often in the hands and feet
• Not being able to feel heat, cold, or pain, such as a cut on your foot
• Pain from even light touch

• A heartbeat that's too fast or too slow
• Trouble swallowing
• Sweating too much or too little
• Vomiting, diarrhea, or constipation
• Problems with urination or sexual function

Symptoms may range from mild to very strong. They may develop quickly over days or slowly over months and years. But they are rarely life-threatening.

To find out if you have a peripheral nerve disorder, your provider will:

• Ask about your medical history
• Ask about your family health history
• Do a physical exam
• Order tests, which may include:
  • Blood tests
  • Genetic tests
  • Nerve tests that measure:
    • Electrical activity in your nerves and muscles
    • How well your autonomic nerves are working
  • A biopsy of nerve or skin tissue
  • CT or MRI scan to see what may be pressing on your nerves

It's important to treat any conditions that are causing nerve damage. In certain cases, that will allow your nerves to heal over time.

Treatment for symptoms depends on the type of peripheral nerve disorder you have, where it is, and how severe. Treatment options include:

• Braces or splints
• Over-the-counter patches and skin creams
• Prescription medicines
• Non-drug pain management, such as electrical stimulation or relaxation therapy
• Surgery to relieve pressure on a nerve

You can help prevent peripheral nerve disorders by:

• Managing health conditions that may cause nerve damage, especially diabetes
• Preventing falls and accidents
• Avoiding toxic substances
• Being careful to avoid repeated motions and body positions that press on your nerves
• Eating a balanced diet, exercising, limiting alcohol, and not smoking

NIH: National Institute of Neurological Disorders and Stroke