There are several causes of a pinched nerve, such as carpal tunnel syndrome. Discover other causes, their signs and symptoms, and your treatment options.

A pinched nerve results from something inside or outside your body pressing against a nerve. The compressed nerve then becomes inflamed, which causes symptoms.

The medical terms for a pinched nerve are nerve compression or nerve entrapment.

A pinched nerve can happen almost anywhere in your body. One of the more common locations of a pinched nerve is your arm. Areas where nerves travel through a narrow space, such as your elbow or wrist, can be more prone to nerve compression.

If you’re having any symptoms of a pinched nerve, talk with a doctor. They can make a diagnosis and help determine your next steps.

A pinched nerve can happen when the nerve gets compressed or squeezed. Nerves travel down your arm, and there’s potential for the nerve to be pinched by a bone, muscle, or tendon.

The three main nerves in your arm and their approximate paths are:

  • the median nerve, which runs down the center of your arm
  • the radial nerve, which runs down the thumb side of your arm
  • the ulnar nerve, which runs down the little finger side of your arm

These nerves or their branches can get pinched in several places as they travel down your arm. This often occurs near your elbow or wrist, where bones and other structures form tunnels and small passageways your nerves must travel through.

Sensory nerves send information to your brain about what your body is sensing around you. Motor nerves send signals from your brain to your body, especially your muscles, telling it how to react to the information. Some nerves have both sensory and motor functions. When these are pinched, both types of symptoms can occur.

Common causes

There are several causes of a pinched nerve in your arm. A nerve can be compressed at any point as it travels down your arm. Bone and tissue structures around your wrist and elbow mean that nerves are more prone to getting pinched around those areas.

Here are some of the more common causes of a pinched nerve in your arm.

Median nerve compression

Carpal tunnel syndrome (CTS) is the most common nerve compression syndrome. The median nerve gets compressed as it travels through the carpal tunnel in your wrist. The carpal tunnel is a tight space in the wrist with lots of bones and tendons.

Repeatedly extending and flexing your wrist can lead to compression by reducing the size of the carpal tunnel. Repetitive movements of your wrists frequently cause carpal tunnel syndrome.

Ulnar nerve compression

The second most common nerve compression syndrome is cubital tunnel syndrome.

Cubital tunnel syndrome happens when the ulnar nerve gets compressed as it runs through the cubital tunnel. The cubital tunnel is a tight space around your elbow.

Cubital tunnel syndrome can also happen as the nerve goes through another tight spot in the elbow area. It usually happens when you keep your arm bent for a long time, such as when you rest your arm on the window ledge of your car while driving or lean on your elbows at a table.

Radial nerve compression

The radial nerve is located near your elbow and branches into the posterior interosseous and superficial nerves.

The posterior interosseous nerve is the branch that travels deeper into your arm. The superficial nerve is closer to the surface of your skin. Both branches can be compressed commonly by repeatedly twisting your forearm.

Radial tunnel syndrome

This is when the superficial branch (which is close to the surface) of the radial nerve gets pinched. It travels through the radial tunnel and several other tight spots around your elbow, where it can be compressed.

Less common causes

Below are some additional reasons for a pinched nerve. Some are similar to more common causes of a pinched nerve. A doctor will diagnose your condition based on your symptom history and any recommended testing.

Pronator teres syndrome

The median nerve can be compressed by the muscles in your forearm below your elbow.

The symptoms are the same as carpal tunnel syndrome, except the numbness can extend into your palm, and you may feel pain in your forearm and elbow. Unlike carpal tunnel syndrome, it usually doesn’t cause symptoms at night.

Anterior interosseous nerve syndrome

The anterior interosseous nerve is a motor nerve branch of the median nerve. A motor nerve is involved with muscle function. Compression of this nerve can occur at one or more sites in your forearm. It causes weakness in your thumb and index finger, making it hard to grip a pencil or make the “OK” sign.

Other symptoms are weakness when twisting your forearm and vague forearm pain.

Ulnar tunnel syndrome

This uncommon condition occurs when the ulnar nerve is compressed in a tunnel on the pinkie side of your wrist. Cubital tunnel syndrome is also compression of the ulnar nerve, but the compression happens around the elbow, not the wrist.

Usually, ulnar tunnel syndrome is caused by a ganglion cyst or chronic and repetitive wrist trauma (like a cyclist gripping a handlebar).

The symptoms in your ring finger and pinkie can be motor, sensory, or both depending on the site of compression.

Motor nerves support normal muscle movement. When nerve compression interrupts communication with the muscle, it can cause muscle weakness. Compression on a sensory nerve interferes with messages about what you are sensing.

Sensory symptoms include tingling or pain. Unlike cubital tunnel syndrome, ulnar tunnel syndrome doesn’t affect the back of your hand.

Superficial sensory nerve compression

In the area of your wrist, there is a sensory nerve branch of the radial nerve. Anything that fits tightly around your wrist, such as handcuffs or a watch, can compress the radial nerve here. Leaning on your forearm for a long time is another cause.

The symptoms are numbness and tingling on the top of the thumb side of your hand, sometimes with forearm and wrist pain.

Posterior interosseous nerve syndrome

The posterior interosseous nerve is the branch of the radial nerve that travels deeper into the muscle groups of the forearm. This goes through several tight spots near your elbow, including the radial tunnel. It can be compressed as it travels through any of these areas.

Yes, you can pinch a nerve in your armpit.

Your axillary nerve starts in your neck and runs through your armpit before crossing over your upper arm bone (humerus). It branches into a motor nerve to your shoulder muscles (deltoid and teres minor) and a sensory nerve to your shoulder.

Your axillary nerve can be pinched by:

Possible symptoms include:

  • shoulder ache
  • fatigue in your arm muscles while you perform overhead movements
  • difficulty lifting or rotating your arm
  • numbness and tingling on the side and back of your upper arm

Can you get a pinched nerve in your arm from sleeping on it?

Yes, you can!

Sleeping with your head on your wrist or in a position that puts constant pressure on your elbow can cause a pinched nerve. The median nerve at your wrist and the ulnar nerve at your elbow are most vulnerable because they’re close to the surface in these locations.

A nerve becomes inflamed when it’s pinched, which causes varying symptoms depending on the type of nerve involved.

Signs and symptoms can be a combination of sensory and motor symptoms.

Here are some of the signs and symptoms of a pinched nerve in the arm:

Carpal tunnel syndrome symptoms

The median nerve is a sensory nerve for your thumb, index finger, middle finger, and half of your ring finger.

Carpal tunnel syndrome causes numbness, tingling, and pain in those areas. The symptoms may radiate up into your arm and shoulder. The symptoms are frequently worse at night.

The median nerve is also a motor nerve to your thumb, so CTS can cause thumb weakness and clumsiness too. This can make it hard to grip things. As CTS becomes more severe, you may notice thinning of the muscles in the bulge under your thumb called the thenar eminence.

Cubital tunnel syndrome symptoms

The ulnar nerve supplies sensation and motor to your little finger and half of your ring finger.

Compression causes numbness and tingling (but not pain) in those fingers and weakness in the small muscles in your hand. Eventually, muscle thinning can occur, moving your fingers into abnormal positions.

Radial nerve compression symptoms

Symptoms of radial nerve compression typically come on very gradually. You feel these symptoms in the back of your hand and into your wrist and forearm.

Symptoms include reduced sensation, pain, and a prickling sensation. If you have radial nerve compression, it may be hard to keep your middle finger straight when you extend your elbow.

Radial tunnel syndrome symptoms

The superficial branch of the radial nerve is a sensory nerve. It’s not very deep, so it’s easily compressed by anything that puts pressure on your forearm.

When compressed, it causes an achy pain in your forearm that may radiate to your elbow. The symptoms are very similar to tennis elbow.

Posterior interosseous syndrome symptoms

The posterior interosseous nerve is a motor nerve that serves the small muscles in your fingers, thumb, and wrist.

Compression makes it difficult to extend your fingers and thumb straight out. It also affects your ability to turn the thumb side of your wrist toward your forearm.

A doctor may be able to diagnose a common pinched nerve, like CTS, based only on your symptoms and an examination.

When needed, a doctor may also use one or more of the following tests to make or confirm a diagnosis.

  • X-rays: This test is not often helpful but may reveal another diagnosis, like a fracture.
  • MRI: An MRI is occasionally used to clarify a diagnosis or reevaluate a pinched nerve that’s not getting better.
  • Electromyography: This test shows electrical activity in a muscle.
  • Nerve conduction study: This test shows the speed of nerve signals.
  • Ultrasound: An ultrasound is sometimes used to evaluate a nerve.

If you have a pinched nerve, a doctor will always recommend you try conservative therapy first, with the goal of reducing pain and improving function.

Rest

It’s important to rest your arm as much as possible to allow it to heal.

Over-the-counter pain medication

Anti-inflammatory medication such as ibuprofen (Advil, Motrin) or naproxen (Aleve, Naprosyn) can reduce the inflammation in the nerve, relieving symptoms.

Heat or ice

Applying heat or ice over the pinched nerve can help relieve your symptoms. Be careful not to burn or freeze your skin if your sensation is decreased.

Experts typically recommend limiting yourself to 20 minutes of heat or 20 minutes of ice at a time.

Splint

You may use a splint to limit the movement in your wrist, elbow, or arm, or to support weak muscles. This reduces strain and helps to manage symptoms.

Corticosteroid injection

CTS can be treated with one or two corticosteroid injections. They can help reduce inflammation and ease the pressure on your nerve.

However, they’re not long-term treatments. Many people with carpal tunnel syndrome will still need surgery.

Corticosteroid injections don’t help everyone, but it’s estimated that 75% of people have some improvement with this treatment. Research shows that corticosteroid injections are still effective at least 10 weeks later. Beyond that, symptoms typically come back.

Surgery

Surgery to release pressure on the nerve is routinely performed for most nerve compression syndromes. You might be a good candidate for surgery if:

  • your symptoms don’t improve after three to six months of conservative therapy
  • your symptoms are severe
  • muscle thinning or muscle loss occurs

Surgery for carpal tunnel syndrome is the most common type of surgery done for a pinched nerve. There are around 600,000 carpal tunnel release surgeries performed in the United States every year. It has high success rates at improving or resolving symptoms of carpal tunnel syndrome.

Recovery time varies depending on a number of factors, including:

  • the nerve involved
  • the seriousness of the injury
  • how the injury responds to conservative therapy
  • the need for surgery
  • the work or activities you’ll return to

Pinched nerves due to temporary pressure on a superficial nerve usually resolve on their own within hours. Those caused by a ganglion cyst won’t improve until the cyst is removed.

Stretches to maintain flexibility or to maintain or build muscle strength can be very helpful for pinched nerve symptom relief, healing, and prevention.

The following articles describe stretches and exercises for your arms and wrists:

Before starting an exercise program, talk with a doctor to be sure it’s safe and it won’t cause further injury. A doctor can also refer you to a physical therapist who can design a routine specifically for you.

Stop an exercise immediately if it causes significant discomfort or pain.

Here are some things you can do to prevent a pinched nerve from recurring:

  • Minimize or avoid the repetitive movements and activities that cause it.
  • If your injury was work-related, you may have to change how you use your hands and arms to perform your job.
  • If you can’t do your work without repetitive movements, you might need to consider changing jobs.
  • Change your hand and arm position frequently while performing an activity.
  • Take frequent breaks to rest or stretch your wrists and arms.
  • Avoid any activities and positions that put pressure on superficial nerves.
  • Make sure you aren’t putting pressure on superficial nerves while sleeping.
  • Rest your arms as much as possible throughout the day.

A pinched nerve happens when structures around the nerves put pressure on it. It’s most likely to happen where the nerve travels through a tunnel or other small space in the arm.

Symptoms can include numbness, tingling, pain, or muscle weakness. Treatments include rest, hot or cold treatments, medications, physical therapy, or sometimes surgery.

The best way to prevent the recurrence of a pinched nerve is to avoid the activity or repetitive movements that initially caused it.