People living with multiple sclerosis (MS) can experience many different symptoms from the nerve damage caused by MS. For some, their fingers bend or curl inward toward their palm.

“Does anyone experience their fingers curling into a ball? Or when you hold your hand out, your index finger falls down and the pinky goes up?” asked one MyMSTeam member.

People with MS may experience their fingers curling up involuntarily due to symptoms of MS or from an unrelated condition.

What Does MS Hand Curling Look Like?

If you’re living with MS, you may experience your fingers curling inward toward your wrist or palm. It may be difficult to extend or open your hand. This condition can be temporary or permanent, depending on the cause.

Members have described how involuntary hand curling affects them: “My left hand is curled up in the morning. I have to pry my fingers open, and I have a lot of itching.”

Fingers that curl inward toward the upper limb can make the hand look like a claw, which is where the term “claw hand” comes from.

Another member said, “Digging my nails into my palm and having the ‘claw’ issue causes me to constantly stretch my palms and fingers.”

Impact of MS Hand Curling

Involuntary hand curling may affect motor function and impact how well you can use your hands. Even if you have little to no MS-related abnormalities in the rest of your body, the condition can severely affect your hand function. In a study of more than 20,000 people with MS, about 60 percent were experiencing hand function impairment when they were diagnosed. Lost sensation, strength, or motor control forced more than 40 percent of those people to make adjustments in their daily life.

Difficulty with using your hands is a common early symptom of MS. “My MS started with two fingers on my left hand. Gradually, all of my fingers felt a diminished sensation at the fingertips,” said one MyMSTeam member.

Peripheral neuropathy, which causes diminished or unusual sensations in your hands, is another common symptom of MS.

Having impaired manual dexterity (ease of using your hands) can reduce your level of independence. You might find it harder to complete tasks of daily living, such as getting dressed, cooking, and using the toilet. A MyMSTeam member shared, "My hands will spasm into claws so badly that I refrain from driving any farther than the store.”

Working may also become more difficult if you can’t use your hands. In countries that link health insurance and employment, keeping your job is essential to maintaining access to affordable health care.

Why Involuntary Hand Curling Occurs

Any condition that affects the nerves in the hand can cause your fingers to bend inward. Involuntary hand curling can be congenital (present at birth) or develop after an injury or a health condition. People with MS can experience finger curling as a symptom of MS or an unrelated condition.

Other possible causes or risk factors of finger curl include:

• Injury — The ulnar nerves, which run on either side of your neck through your arms to your hands, become damaged.
• Nerve entrapment — Nerves in the arm or hand are compressed against the bone.
• Cubital tunnel syndrome — The ulnar nerve, which controls small hand muscles, gets squeezed into the elbow.
• Congenital differences — The hand forms in an unusual way in the uterus.
• Fibrosis — Thick scar tissue builds in hands or fingers after an injury or severe burn.
• Dupuytren’s contracture — A knot formed below the skin pulls on and bends the fingers, most frequently involving the ring finger and the pinky.
• Carpal tunnel syndrome — The median nerve, the main nerve in your arm that extends to your hand, gets squeezed in your wrist, causing numbness and tingling sensations.

Rarely, an infection such as leprosy can cause involuntary hand curling.

MS Symptoms That Can Cause Fingers To Curl

MS is an autoimmune disease where your body mistakenly attacks the nerves of your own central nervous system (CNS), which includes your brain and spinal cord. People living with MS can experience a wide range of symptoms based on which part of the body is affected. If MS causes a lesion (damage) that affects how your nerves communicate with the muscles of your arms or hands, it could cause your fingers to curl up involuntarily.

Spasticity (involuntary muscle spasms or stiffness), muscle spasms, and joint contractures are possible symptoms of MS that can cause your fingers to curl.

Spasticity

MS spasticity is one of the most common symptoms experienced by people with MS. In findings from a large U.S. survey, more than 80 percent of people with MS had some form of spasticity. This symptom usually involves the legs, but it can affect any limb. If spasticity occurs in the arms or hands, it could cause involuntary hand curling.

There are two types of spasticity: flexor and extensor. In flexor spasticity, tight muscles keep affected joints bent and hard to straighten. In extensor, tight muscles keep joints straight and hard to bend.

Spasticity can happen for no reason, or it can be triggered or worsened by trigger factors such as:

• Sudden movements
• Changes in temperature or humidity
• Bladder or bowel changes
• Infections
• Tight clothing
• Stress

Muscle Spasms

Between 40 percent and 80 percent of people with MS experience muscle spasms. These involuntary muscle contractions can last for a long time or happen briefly, causing sudden movements. If a muscle spasm occurs in a muscle controlling your hands, it may cause your fingers to curl.

Joint Contractures

A joint contracture refers to a joint that is frozen or immobilized. Joint contractures are a common symptom of people living with MS. Untreated spasticity can cause muscles and ligaments (bands of tissue around joints) to harden, limiting the range of motion of the affected joint.

An immobilized joint could also contribute to muscle weakness. If a joint contracture keeps your hand from working, the muscles can atrophy (become thinner) from the lack of use. It’s important to treat any spasticity and muscle spasms in your hand to prevent a situation where your fingers are permanently bent in a curling position.

Diagnosis of Finger Curling

Claw hand is diagnosed by a neurologist — a doctor specializing in treating diseases of the brain, spinal cord, and nerves.

The doctor will perform a physical examination to see how you bend and move your fingers and hands. They may also use an electromyography (EMG) test, which checks for nerve damage by measuring electrical activity when you move your muscles.

Treatment of Involuntary Hand Curling

If your fingers are curling involuntarily, your treatment will depend on your symptoms and the cause of the abnormality. Talk with your medical team, including your neurologist, about the best approach for you. They may start with a noninvasive approach, such as having you wear a splint or a brace. Or they may consult a physical or occupational therapist who can recommend physiotherapy options.

If muscle spasms are causing your fingers to curl up, you may take medications, such as baclofen (Lioresal) and tizanidine (Zanaflex), to relax your muscles.

Physical therapy and stretching exercises can help you gain strength and flexibility in your hands and fingers. An occupational therapist can help you learn strategies to make everyday tasks, such as showering or bathing, easier so you can remain as independent as possible.

Your physical therapist may also recommend wearing a splint or a brace to help hold your fingers straight.

Some cases of MS hand curling may benefit from treatment with onabotulinumtoxinA (Botox). Botox is a temporary muscle relaxant that’s used to treat involuntary hand curling, as well as other symptoms of MS. You may also be a candidate for vascular, nerve, or musculoskeletal surgery to repair nerve injury or tendons.

Talk With Others Who Understand

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

Have you experienced involuntary hand curling or claw hand? Do you have tips for making daily tasks easier to accomplish? Share your experience in the comments below, or start a conversation by posting on MyMSTeam.