Identifying the cause of new symptoms, such as arm pain or weakness, can be challenging if you’re living with multiple sclerosis (MS). Are your tired, achy, tingly arms and hands related to MS or something else entirely, like carpal tunnel syndrome?

Symptoms of carpal tunnel syndrome and MS can overlap, and it’s also possible to have both. But there are ways to tell whether your arm pain and weakness is more likely related to one condition than another. Read on to learn about carpal tunnel syndrome in MS and its causes, symptoms, and the treatment.

What Causes Carpal Tunnel Syndrome?

Carpal tunnel syndrome affects the hand and forearm, causing numbness, tingling, weakness, and pain. This can happen when the median nerve, a primary nerve to the hand, becomes squeezed in a tight space — the carpal tunnel — as it travels through the wrist. The carpal tunnel is made up of bones and a ligament inside the wrist, along with the median nerve and some tendons. When there’s too much pressure on the median nerve, it swells and may cause nerve damage, which can affect the hand function.

Carpal tunnel syndrome is one of the most common nerve conditions, affecting about 3 percent to 6 percent of adults.

Common Symptoms of Carpal Tunnel Syndrome

Symptoms of carpal tunnel syndrome come on gradually and typically get worse over time if not treated. Generally, people first experience tingling and numbness (also a common MS symptom) in their hands or the fingers. The thumb, index, middle, and ring fingers tend to be the most affected, and the pinkie usually is not involved. Since this type of pain is related to problems with the nerves, it’s known as neuropathic pain.

One MyMSTeam member described symptoms in their fingers: “I’m going in for a consultation for my hand for my carpal tunnel. Both of my thumbs lock up, and three-and-a-half out of five fingers go numb to the point of pain.”

Some people also experience electric shock-like feelings that can travel up from the fingers to the wrist, arm, and shoulder. These sensations are often triggered by a motion, such as holding a phone or steering wheel, writing, or typing, and may awaken you during the night. “Terrible carpal tunnel in both arms — didn’t sleep well at all,” wrote one MyMSTeam member.

Sometimes, people simply give their hands a shake to relieve the numbness or tingling, but the sensations can eventually become constant. Hand and arm weakness is common, too, and you might begin to drop objects because of a weak or numb thumb — the median nerve is responsible for the fingers’ pinching motion. Over time, you might have trouble with fine motor movements, such as buttoning a shirt. In severe cases of carpal tunnel syndrome, the thumb can become smaller.

Pinkie Pain? Probably Not Carpal Tunnel Syndrome

Upper-extremity weakness and sensations of numbness, tingling, and pain are all neurological symptoms of MS, too. One clue to telling the conditions apart is that if your pinkie is involved, you can likely rule out carpal tunnel syndrome.

Even health care professionals occasionally mistake MS for carpal tunnel or vice versa. One MyMSTeam member described their misdiagnosis. “So, I went to the ortho because I was diagnosed with carpal tunnel in 2009, and he tells me I don’t have carpal tunnel, but that it was MS masking itself as carpal tunnel,” they said. “So I’ve had MS as far back as 2009.”

Can MS Raise Your Risk of Carpal Tunnel Syndrome?

MS affects the central nervous system (CNS), which includes the brain and spinal cord, whereas carpal tunnel syndrome affects the peripheral nervous system (nerves outside the CNS). Studies looking at carpal tunnel syndrome in people with MS have been few and small, but they show some evidence that carpal tunnel syndrome may be more common in people with MS. One 2018 study of 75 people with MS found that 28 percent of participants also had carpal tunnel syndrome.

Older Age and Use of Mobility Aids

Using mobility aids for MS, such as crutches or canes, increases the risk of developing carpal tunnel syndrome. A small 2020 study found that people with both conditions tended to be older and had lived with MS longer than those who had MS but not carpal tunnel syndrome.

In an earlier study, researchers also suggested that wheelchair and mobility aid use, which involves repetitive (continuous) hand motions, could lead to a high prevalence of carpal tunnel syndrome among people with MS. The findings also linked older age with more severe carpal tunnel syndrome.

More research is necessary to determine if having MS makes you more likely to develop carpal tunnel syndrome, but using mobility aids — common among people with advanced MS — does seem to increase the risk.

Other Risks Factors for Carpal Tunnel Syndrome

There’s no one specific cause of carpal tunnel syndrome, but a variety of factors make you more likely to develop it. Risk factors of carpal tunnel syndrome include the following:

• Repetitive and frequent hand movements, such as typing
• Repetitive and frequent grasping movements used in sports or factory assembly lines
• Hormonal changes in people with thyroid problems or going through menopause
• Fractures or dislocations of the wrist
• Bone or joint diseases, such as osteoarthritis
• Inflammatory autoimmune diseases, such as rheumatoid arthritis
• Blood sugar changes, as seen in type 2 diabetes
• Use of anastrozole (Arimidex), a drug to treat breast cancer
• A higher body weight
• Family history of carpal tunnel syndrome

According to the National Institute of Neurological Disorders and stroke, women are three times more likely than men to have carpal tunnel syndrome. The authors of the 2018 study found that people aged 40 to 60 also are at greater risk.

Treatment of Carpal Tunnel Syndrome

If you’re concerned about numbness, weakness, or pain in your arm, hand, or fingers, it’s important to see your doctor to get the right diagnosis. Early treatment of carpal tunnel syndrome is best, since it’s a condition that gets worse over time. When symptoms first begin, you may be able to manage them by applying ice packs, taking breaks often to rest your hands, and avoiding anything that makes the pain worse. However, if you have numbness, it’s important that you see a neurologist.

Conservative Treatment

If at-home measures like ice and rest don’t provide enough relief, the next step might involve wrist splinting, especially at night, and pain relief medications.

First-line medications for short-term pain relief typically include nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin), but these over-the-counter medications don’t treat the condition itself. For that, corticosteroids such as cortisone can be injected directly into the carpal tunnel to reduce inflammation of the median nerve, thereby relieving symptoms.

These treatment options are more likely to work if your symptoms are occasional, have lasted less than 10 months, and are mild or moderate.

Surgery

If conservative treatments don’t work or your symptoms are severe, you might consider carpal tunnel surgery. In this procedure, your surgeon relieves pressure on the median nerve by cutting the ligament that’s pushing against it. Two types of surgery are available — endoscopic and open — and both achieve good results and patient satisfaction.

In endoscopic surgery, the surgeon uses a device with a camera attached to look inside the carpal tunnel region. They can then cut the ligament, making small incisions in your wrist or hand. This type of surgery can lead to less pain compared with open surgery.

Open surgery involves a larger incision into the palm of your hand, directly above the carpal tunnel, so the surgeon can access the ligament and reduce pressure on the nerve. Your skin will heal in a few weeks, but internal healing will take several months. You may be given physical therapy during recovery, and your doctor will likely encourage you to gradually return to normal use of your hand.

Talk With Others Who Understand

MyMSTeam is the social network for people with MS and their loved ones. On MyMSTeam, more than 198,000 members come together to ask questions, give advice, and share their stories with others who understand life with MS.

Have you been diagnosed with both carpal tunnel syndrome and MS? What do you do to help relieve the tingling and pain? Share your experience in the comments below, or start a conversation by posting on your Activities page.