Carpal Tunnel Syndrome

Medically Reviewed by Zilpah Sheikh, MD on May 15, 2024
11 min read

Carpal tunnel syndrome, also called median nerve compression, is a condition that causes numbness, tingling, or weakness in your hand.

Your symptoms are caused by pressure on your median nerve, which runs the length of your arm and enters your hand through a passage in your wrist called your carpal tunnel. Your median nerve controls movement and feeling in your thumb, index, middle, and ring fingers.

Your symptoms will usually come on slowly. Symptoms often start in one or both hands at night and go away during the day, or they come and go throughout the day and night. As your symptoms get worse, you may have them during the day, they may last for longer, or they may happen more often.

Symptoms may include:

  • Numbness, tingling, burning, pain, or weakness in your fingers, especially your thumb, index, and middle fingers, and possibly the thumb side of your ring finger
  • Shock-like feelings that sometimes spread into your thumb, index, middle, and ring fingers
  • Pain or tingling that may travel up your forearm toward your shoulder
  • Trouble holding onto things because your hand is weak, numb, or your can't feel where your hand is in space

You may sleep with your wrists bent, which can make your nighttime symptoms worse. This may wake you up during the night. During the day, you may have symptoms when you hold something with your wrist bent forward or backward for a long time, such as when you drive, hold a book, or hold your phone.

Early on, shaking out your hands might help you feel better. But after some time, it may not help as much. As carpal tunnel syndrome gets worse, you may have less grip strength because the muscles in your hand shrink or degrade or atrophy. You may also have more pain and muscle cramping.

Rheumatoid arthritis

Rheumatoid arthritis is an autoimmune condition where your immune system attacks the tissues that line your joints. Carpal tunnel syndrome and rheumatoid arthritis have similar symptoms, such as weakness, numbness, tingling, reduced function, and morning stiffness in your hands and wrists. The main difference is in where you get symptoms.

With carpal tunnel syndrome, you only have symptoms in your hands and wrists, usually just on one side. With rheumatoid arthritis, symptoms often start in both your hands and wrists, but you may also have symptoms in your other joints, skin, eyes, heart, and lungs. Over time, you may also have symptoms such as fatigue, a low-grade fever, and weight loss with rheumatoid arthritis.

Tendinitis in your wrist or hand

Tendinitis is a condition where the tissue that connects your muscles to your bones (tendons) gets irritated or inflamed and swells. It's usually caused by strain or injury from repetitive use. Carpal tunnel syndrome and tendinitis can have similar symptoms, such as stiffness, pain, swelling, and reduced range of motion or function. Again, the main difference is in where you get symptoms.

With carpal tunnel syndrome, you have discomfort, tingling, or numbness in your fingers and palm. With tendinitis, you will usually have pain near your swollen tendon that gets worse when you move your wrist or hand in ways that use that tendon.

Researchers don't yet know what causes carpal tunnel syndrome. But they think it may be from different things that put pressure on your median nerve and the tendons in your carpal tunnel. Once your tendons are irritated, they may swell, which narrows the carpal tunnel further. This may put even more pressure on your median nerve. 

 

 

 

Some of the things that may make it more likely for you to have swelling or inflammation in your wrists include:

  • Injury to your wrist, such as a sprain, dislocation, or a bone break
  • Having mechanical problems in your wrist joint that you may have been born with
  • Regular use of vibrating machinery
  • Having a job where you use forceful gripping motions over and over
  • Disorders of your pituitary or thyroid glands
  • Having rheumatoid arthritis or another autoimmune condition that causes swelling in your joints and tendons
  • Having diabetes or another metabolic disorder that makes your nerves vulnerable to compression
  • Retaining fluid, as you may during pregnancy or menopause
  • Being older than age 40
  • Being assigned female at birth (AFAB)

 

 

Tests your doctor may use to diagnose carpal tunnel syndrome include: 

Laboratory and imaging tests, such as an ultrasound, X-ray, or MRI

Your doctor may order one of these tests to rule out other causes of wrist and hand pain. An X-ray can show arthritis or a broken bone. An ultrasound or magnetic resonance imaging (MRI) scan will show a swollen or compressed median nerve. They’ll also tell the doctor why it is being squeezed, whether it’s arthritis, carpal tunnel syndrome, or another reason.

They might also order lab tests, like bloodwork, to look for diseases like diabetes that can damage your nerves.

Electrophysiological tests

Nerve conduction velocity test

This test provides some of the strongest evidence of carpal tunnel syndrome. It measures how fast an electrical signal can travel along a nerve or from the nerve to a muscle.

The doctor places a small electrode on your skin near your elbow. It sends a mild electrical current down your median nerve. The more time it takes for the current to travel from your elbow to your fingers, the more damage to your median nerve.

Electromyogram

This works like the second part of the nerve conduction velocity test. It measures how well the muscle around your median nerve works. The doctor places a small needle electrode into muscles in your hand and arm that get impulses from the median nerve. The needle sends electric impulses into the muscle. You relax and flex your hand several times. The doctor can tell if your median nerve is damaged or being squeezed.

The needles might hurt a little, but the pain should stop once the doctor takes them out. You may feel twitches or spasms from the electrical current. You could have some bruising where the electrode went in, but that should go away within a few days.

Your doctor will ask you about any patterns with your symptoms. For example, if you have tingling or numbness in your little finger, it may not be carpal tunnel syndrome since the median nerve doesn’t provide feeling to that finger. Your doctor may also ask if you have a history of numbness, tingling, pain, or weakness in your hand at night or while holding your phone. These symptoms suggest carpal tunnel syndrome. 

Some physical tests your doctor may do include:

Tinel’s sign

The doctor will tap or press on the median nerve in your wrist with a reflex hammer. If your fingers tingle or if you feel an electric-shock-like sensation, the test is positive. You may have carpal tunnel syndrome.

Phalen’s maneuver

This is also known as the wrist-flexion test. The doctor will tell you to press the backs of your hands and fingers together with your wrists flexed and your fingers pointed down. You’ll stay that way for a minute or two. If your fingers tingle or get numb, you have carpal tunnel syndrome.

Two-point discrimination test

This means you can tell if two objects touching your skin are two distinct points instead of just one. The doctor may use a gadget called a 2-point disk-criminator, a small, flat, eight-sided tool with needle-like prongs sticking out from all sides.

They might do the test several times on each finger. They’ll start with two points touching your skin a few centimeters apart and move them closer together until you feel just one point of pressure.

The distance at which you can feel only one point will help them figure out nerve function and compression – two important parts of carpal tunnel syndrome.

Your treatment will depend on your symptoms and how far your condition has progressed. Also, if your carpal tunnel syndrome is caused by something like diabetes or rheumatoid arthritis, your doctor will treat that first. To directly treat your symptoms, your doctor may try:

Bracing on splinting. Wearing a brace or splint may keep you from bending your wrist, especially at night. This keeps your wrist stable in a neutral position and may lessen the pressure on your median nerve. You may also consider wearing a brace during the day when you do activities that trigger your symptoms or make them worse.

Medication. Your doctor may suggest you take a nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen or naproxen, which can ease your pain and inflammation.

Your doctor may also suggest getting a cortisone shot in your wrist. Cortisone is a very potent anti-inflammatory that can bring your swelling down and relieve your pain.

Activity changes. If repetitive motion is causing your symptoms, try changing the activity that's triggering your symptoms. For instance, take breaks more often, use ergonomic tools and furniture, lessen your repetitive movements, and use an ice pack as needed to reduce swelling.

Exercises. Stretching or strengthening moves can help you feel better. Nerve gliding exercises may help your median nerve move better within your carpal tunnel. Ask your doctor to recommend specific exercises, or ask about seeing a physical therapist. A physical therapist can help you come up with changes and an exercise routine to help ease your symptoms and keep things from getting worse.

Carpal tunnel syndrome surgery

If none of those treatments work or only help for a short time, your doctor may recommend you have surgery. The procedure is called a carpal tunnel release. During the surgery, your surgeon will cut your transverse carpal ligament, which makes the "roof" of your carpal tunnel. Cutting this ligament makes your carpal tunnel bigger, which can ease pressure on your median nerve. It also allows blood to flow better into your carpal tunnel, which helps your nerves work better.

Surgery can relieve your symptoms fast, but this depends on how severe they are. In some cases, full recovery can take months or even years. But most of the time, surgery is a permanent treatment for carpal tunnel syndrome.

Surgeons use a couple of procedures for carpal tunnel release:

Open release. Your surgeon will make a cut in your wrist to reach and cut your transverse carpal ligament. This is usually done with local anesthesia in an outpatient facility, so you won't need to stay overnight in the hospital. Sometimes, your ligament may grow back together after this surgery. But when this happens, it usually grows back longer than it was before the surgery, so it should work long-term to relieve your symptoms.

Endoscopic release. Your surgeon will make two small cuts in your wrist and palm and insert a mini camera through one cut and a special knife through the other. They will use the camera to find your ligament and the special knife to cut it. This type of surgery usually causes less pain and has a faster recovery than open release. But you may have a higher risk of complications and may be more likely to need another surgery.

Hand and wrist exercises may help your median nerve move more freely, which can help ease your symptoms. Exercises work best when you use them along with other treatments, such as making activity changes and using a wrist brace or splint. They may also help after an injury or carpal tunnel release surgery to prevent scarring, which can make your symptoms worse.

Here are a few exercises you can try:

Median nerve glides

Before you do this, use mild heat for 15 minutes on your affected wrist. After you're finished stretching, use an ice pack for 20 minutes. This will help prevent swelling. Hold each step of this exercise for about 3-7 seconds and repeat 10-15 times per day.

  • Make a fist with your thumb outside your fingers.
  • Extend your fingers straight upward, keeping your thumb close to the side of your hand. 
  • Keep your fingers straight while you bend your hand backward toward your forearm.
  • Keep your hand in this position while you extend your thumb away from your fingers. 
  • Keep your hand in this position while you turn your forearm so your hand is palm up.
  • Use your other hand to gently pull your thumb back, deepening your stretch. 

Wrist extensor stretch

Experts recommend doing this exercise a few times each day, especially before activities that tend to worsen your carpal tunnel syndrome.

  • Hold your hand out in front of you, as if you're signaling someone to stop.
  • Using your other hand, gently pull back on your fingers until you feel a stretch on the inside of your forearm.
  • Hold for about 15 seconds.
  • Repeat 5 times, then stretch the other hand and wrist.

Wrist flexor stretch

Some experts recommend doing this stretch a few times each day. You may want to do it before any activity that tends to make your carpal tunnel symptoms worse. This may make your fingers numb or make your numbness worse for a while. If the numbness is uncomfortable, stop doing the stretch.

  • Hold your arm out in front of you, with your palm facing down. Bend your wrist so your fingers face the floor.
  • Using your other hand, gently pull your hand toward your body until you feel a stretch on the outside of your forearm.
  • Hold for about 15 seconds.
  • Repeat 5 times, then stretch the other hand and wrist.

You can get complications from the condition or the treatment, including:

  • Permanent median nerve damage that causes impairment or disability
  • Muscle weakness or shrinking at the base of your thumb that can reduce your hand dexterity
  • Chronic wrist and hand pain, which may develop into complex regional pain syndrome
  • Neuroma of your median nerve after carpal tunnel release surgery
  • Scarring, joint stiffness, and feelings like burning, crawling, pin-and-needles, or itching after surgery

 

It can be hard to prevent carpal tunnel syndrome, since it can be hard to know what caused it. But you can help lessen stress on your hands and wrists by:

  • Stretching your wrists and hands before and after you do physical activity
  • Wearing protective gear when at work and during activities
  • Taking breaks to rest your hands.
  • Using good technique and posture while you work. For instance, keep your keyboard at elbow height or lower so your wrists are relaxed and parallel to the floor. 
  • Reducing your force while you type and keeping your hand more relaxed when you grip
  • Keeping your hands and wrists warm can help keep you from getting stiff or sore while you work. If your office is cold, wear fingerless gloves or mitts to keep your hands and wrists warm.

Carpal tunnel syndrome is when irritation causes extra pressure on the median nerve in your wrist. The most common symptoms include numbness, tingling, burning, pain, or weakness in your fingers, especially your thumb, index, and middle fingers, and the thumb side of your ring finger. Your doctor can use a handful of tests to diagnose carpal tunnel syndrome and rule out other causes of hand and wrist pain. Treatment can range from stretching and exercising and wearing a brace to a surgical procedure, called carpal tunnel release. 

How do I know if I have carpal tunnel syndrome?

The most common symptom is numbness, tingling, or pain in your thumb, index, middle, and half of your ring finger. These symptoms tend to be worse at night. The symptoms usually come and go depending on what you do. You may be more likely to have symptoms when you do activities like driving or holding a book or your phone.

Can carpal tunnel go away on its own?

Yes, it's possible for carpal tunnel to go away on it's own, but it's not likely. To increase your chance of healing on your own, rest your hand and wrist and avoid doing repetitive motions. You can get permanent nerve damage if you don't get treatment and it doesn't heal on its own. If you have symptoms of carpal tunnel syndrome, go see your doctor. You can always try nonsurgical treatments before you explore surgery.