Why a Compressed Nerve in Your Spine May Cause Arm Itching (2024)

Brachioradial pruritus is a nerve disorder that causes itching on the skin on the outer side of your forearm. This part of your arm covers the brachioradialis muscle, which works with other muscles to help you flex your elbow. Sometimes the itch can also extend into the upper arm, shoulder, neck and trunk.

While it's not usually a serious health problem, a flare-up of brachioradialis pruritis symptoms can be uncomfortable and hard to treat—partly because experts are not completely sure why it happens.

This article goes over the possible causes of brachioradialis pruritis, what the symptoms are, how it is diagnosed, and how it can be treated.

Brachioradial Pruritus Symptoms

Itching is the classic symptom of brachioradial pruritis. It specifically affects the outer side of the forearm or, sometimes, both forearms. Though rare, the intense itchiness may also be felt elsewhere on the body, like the neck or back.

If you scratch the itchy part of your arm, you may not actually get any relief. In fact, the area may feel even itchier. The scratching that causes more itching is called the itch-scratch cycle.

In some cases, the itching from brachioradialis pruritus can be very distracting and uncomfortable—especially when you are trying to sleep.

Pain may come along with the itching because the same nerves send itching and pain signals to the brain.

Other symptoms of brachioradial pruritus include:

• Tingling in the arms
• A burning sensation in the arms
• Itching of the shoulder and upper back
  

While you might expect to see changes on your skin where it itches, brachioradial pruritis does not cause a rash. However, if you scratch often enough, you may see scratch lines and thickened skin develop where you have previously scratched.

Causes of Brachioradial Pruritus

Brachioradiali pruritus is thought to be caused by nerve irritation or injury. It's not clear exactly why brachioradial pruitus results from these.

However, nerve damage and sun exposure are the two main causes that have been considered. It's possible that both are involved.

Brachioradial pruitus is not contagious.

Nerve Damage

One theory is that brachioradial pruritus can happen to people with degenerative spine diseases. These conditions happen when part of the structure of the spine breaks down. The changes in the spine's stability can place pressure on nearby nerves that connect to the arms.

One example is spinal stenosis. This condition is caused when the center of your spine narrows and presses down on the spinal cord and nerves.

Another example is cervical spondylosis. With this condition, the nerves that exit the spinal cord at the neck are compressed and damaged.

The nerve damage from these conditions may lead to symptoms of brachioradial pruritus.

Sun Exposure

It's also been considered that sunlight might play a role in brachioradial pruritus. Chronic exposure to ultraviolet (UV) radiation can damage the nerve fibers in the skin.

Once they're damaged, the nerves can be more sensitive to the pain and itching from brachioradial pruritus. It's thought that this could be what actually triggers the symptoms in people with cervical spine disease.

Who Gets Brachioradial Pruritus?

Brachioradial pruritus happens twice as often to women as it does to men. While it can start at any age, it's more common in middle age.

Since brachioradial pruritus is often associated with sun exposure, people living in warmer climates might be more at risk for it. That's also why people whose lifestyles include lots of outdoor activities, like gardening or swimming, might be more likely to get it.

Diagnosing Brachioradial Pruritus

This condition can be diagnosed by one of your physicians; you may be referred to a dermatologist or an allergist if symptoms are severe or if the diagnosis is not clear. They can identify the condition based on your symptoms and where on your body you have itching.

Your provider will need to first rule out other possible causes of your itching. For example, if you have a rash and itching, it would be very unlikely that you have brachioradial pruritis. Unfortunately, it's harder to diagnose itchy skin when there is no rash.

A diagnosis of brachioradial pruritus might be considered if anti-itch medications have not helped with your symptoms.

A provider can use several diagnostic tools to determine if you have brachioradial pruritus, including:

• Ice pack test: Many people with brachioradial pruritus notice that putting ice packs on the affected skin is the only thing that gives them relief. A provider may apply ice packs to your skin during an evaluation to see if it helps. If it does, it can make them more sure about the diagnosis.
• X-ray: An X-ray of the cervical spine can be done to make sure there is nothing placing pressure on the nerve roots to the arm. The mages may show degenerative disc disease or osteoarthritis, which are conditions that can point to brachioradial pruritus.
  

Brachioradial Pruritus Treatment

A flare-up of brachioradial pruritus can be hard to treat successfully. Oral antihistamines like Zyrtec (cetirizine), hydrocortisone, and other corticosteroids that are applied to the skin often do nothing or very little to ease discomfort.

Heat also does not help brachioradial pruritus symptoms. People who have tried a heating pad or a soak in a hot bath often find that the heat just makes the itching worse.

Quite a few other treatments have been tried for brachioradial pruritus. Still, the success rate remains mixed. These include:

• Capsaicin cream (suppresses a chemical made in nerve endings)
• Pramoxine cream (numbs sensory nerve impulses in the skin)
• Doxepin cream (antihistamine known to reduce a chemical that causes itching)
  
• Ketamine cream (anesthetic that also provides pain relief)

Some other drugs may help relieve the symptoms of brachioradial pruritis, such as:

• Gabapentin (a seizure drug that may offer relief from the itching)
• Carbamazepine (a seizure drug often used to treat nerve pain)
• Lamotrigine (a seizure drug used to treat itching)
• Amitriptyline (an antidepressant that can be used for pain relief)

Surgical treatment is rarely used to try to correct a nerve problem that may be causing symptoms. Some people also report they find relief throughacupunctureor cervical spine treatmentprovided by a chiropractor.

Summary

Brachioradial pruritus is a disorder that is thought to be linked to spinal nerve damage and sun exposure. It causes itching of the skin over the outside of the forearm that is not relieved by scratching.

Treatment can be difficult, but some people have found success with creams applied to the skin or alternative therapies,

A healthcare provider can diagnose brachioradial pruritus by talking to you about your symptoms, seeing if ice packs relieve the itching, and taking X-rays to look for problems with your spine.