Doctor’s insights into causes of numbness in hands: Five tips to identify urgent medical care

Feel burning or tingling in the hand? When does the numbness start? Where in the hand do you feel numbness?

The numbness in hands is usually less likely to occur than a headache or stomachache. You may easily determine the severity of your headache or stomachache because you might experience them frequently. However, when you experience numbness in the hands for the first time, you might feel nervous and think the symptom more severe than it actually is.

There are also some people who chronically feel hand numbness.

It is important to know which medical specialists you should visit when you feel numbness. Many people tend to visit orthopedics, however there might be other possible causes which orthopedics may not be able to find.

Which medical specialist should you visit when you experience numbness in hands? How do you identify if urgent medical care is required or the condition is not immediately life-threatening?

Neurologist Dr. Yoshiya Hasegawa, who sees many patients suffering from numbness in the hands, provides helpful information regarding what to do when you experience it.

1. Three critical factors for numbness in hands: how and where does the symptom appear?

When people visit a neurologist and complain of “numbness in hands,” there are various types of treatments administered depending on their symptoms. Some are hospitalized immediately for further check-ups, while others leave the clinic without any particular medical treatments. Medical specialists are able to evaluate the necessity of emergency attention from the information provided by the sufferers.

1-1. How does the numbness begin?

It is possible to determine if urgent medical attention is required by observing how the symptom appears: begins suddenly or develops gradually.

For example, it may be life-threatening if someone “experiences numbness in hands suddenly upon waking up.” However, it may be harmless if someone “finds a gradual onset of numbness and not sure when it has begun.”

1-2. Which hand does the numbness appear?

It is possible to determine if urgent medical attention is required by identifying where the numbness appears: in one hand or both hands.

If the numbness occurs in one hand, it can be life-threatening while it may be harmless if it occurs in both hands.

1-3. Which part of the hand does the numbness occur?

It is possible to determine if urgent medical attention is required by identifying where in the hand the numbness appears: does it have the same degree of numbness, or different degree of numbness in thumb side and little finger’s side?

If the numbness affects both thumb and little finger’s side of the hand, it can be life-threatening. However, it may be harmless if it affects the middle, ring and little fingers.

2.Numbness which requires immediate medical visit

Immediate medical visit is required when three critical factors mentioned earlier are fully met. When someone experiences sudden onset of numbness in either hand, which affects both thumb and little finger’s side, it may be caused by cerebrovascular disease.

One must be provided with urgent medical care when numbness is triggered by cerebrovascular disease such as cerebral hemorrhage or cerebral infarction. A head CT will be ordered immediately. However, a head CT will not show any problem when it is taken in six hours after a cerebral infarction has occurred. In this case, a head MRI is ordered as well.

If any lesioned parts are found, the patient has to be immediately hospitalized for treatment.

Cerebral hemorrhage is found by a head CT.

3.Numbness which does not require urgent care

The following three factors should be observed when you experience numbness.

• Does the numbness appear suddenly?
• Does the numbness occur only in one hand?
• Does the numbness occur in both thumb and little finger’s side?

Unless these three conditions occur simultaneously, the symptoms may not be life-threatening or a sign of an emergency that requires a trip to the hospital.

4.The causes of hand numbness

What causes numbness in hands? There are long nerves that extend from the cerebrum and spinal cord travelling down to the peripheral nerves which control muscles. If there is a problem developed either in the cerebrum, spinal cord or peripheral nerves, it causes numbness in hands.

4-1. Numbness caused by a problem in the cerebrum

Cerebral infarction or cerebral hemorrhage causes numbness in hands which requires emergency medical help as mentioned earlier. In this case, sudden onset of numbness which affects only one hand may occur and with the same degree of numbness occurring in both thumb and little finger’s side of hand. It might accompany other symptoms such as paralysis or difficulty with speaking. Call the ambulance immediately if any of these symptoms appears.

4-2.Numbness caused by a problem in the spinal cord

Spine deformity which compresses cervical spinal cord causes numbness in hands. This type of numbness develops gradually and chronically. The symptom appears either in one hand or both hands. Numbness may affect either in the thumb, index and middle fingers or in the middle, ring and little fingers. When you are looking up at the ceiling, tilting your head to the right causes more severe numbness in your right hand and similarly with the left. In short, tilting the neck to one direction increases the degree of the numbness in that side.

Numbness which is developed in the thumb, index and middle fingers is caused by cervical spinal cord compression in C5 and C6, and that which is developed in the middle, ring and little fingers is caused by compression in C6 and C7. Doctors with anatomical knowledge are able to identify problems in cervical spinal cord without an X-ray or MRI.

Problem in cervical spine causes numbness in hands.

4-3. Numbness caused by a problem in the peripheral nerves

Numbness caused by a problem in the peripheral nerves may often appear in both hands and develop gradually and chronically.

However, numbness caused by “carpal tunnel syndrome” which is presented later appears in one hand due to damage in peripheral nerves travelling down from the spinal cord.

5.Other illnesses which cause numbness in hands

Other illnesses other than cerebrovascular disease which requires urgent medical attention are listed below.

5-1. Cervical spondylosis

Outpatients who complain of numb hands may frequently be diagnosed with cervical spondylosis. People who are over 60 years old certainly experience cervical spine deformity. Some people do not show any symptoms of numbness due to the difference in severity. However, if someone in their 50’s begins to feel numbness in the thumb or the little finger, cervical spondylosis is strongly suspected.

This disease does not accompany dysmotility even if left untreated. Many patients may feel relieved when they find that it is not life-threatening. In my opinion, however, it may be better to avoid chiropractic because sudden manipulation to the neck might worsen the symptom.

5-2.Diabetic peripheral neuropathy

Numbness does not appear at the early stage of this disease; it develops numbness in peripheral nerves as the disease progresses. It tends to cause numbness in the legs as well as in hands. Another characteristic includes a presence of numbness in both hands.

Effective treatment involves controlling and managing diabetes. Medication to treat diabetic peripheral neuropathy has to be administered as well.

*Medication to treat diabetic peripheral neuropathy: Aldose reductase inhibitors is commonly used in the treatment of diabetic peripheral neuropathy in order to inhibit activation of the polyol pathway which is considered to be one of the causes of diabetic neuropathy. Epalrestat is commonly used for the treatment of diabetic peripheral neuropathy in Japan. This drug is proven to have a positive effect based on many clinical cases, and especially proven effective on inhibiting initial symptoms. Some studies show that epalrestat helps improve the function of autonomic nerves, and it is one of the drugs which are frequently utilized for the treatment of diabetic peripheral neuropathy.

5-3.Carpal tunnel syndrome

People whose jobs that require working with their hands are more likely to have onset of carpal tunnel syndrome, and I frequently diagnose them with this disease. However, non-specialists may misdiagnose or patients get undiagnosed due to insufficient knowledge of the disease.

The “carpal tunnel” is located in the space at the base of the palm, and nine “tendons” and the “median nerve” all pass through this tunnel from the forearm into the hand. When apoptosis become inflamed and swollen from any causes, the “median nerve” gets compressed. This compression leads to numbness in the thumb and other fingers except the little finger.

If atrophy of the thenar muscles at the base of the thumb occurs or sleep disturbances occurs due to the numbness, surgery performed by orthopedics using locoregional anesthesia will improve the symptoms.

Carpal tunnel located at the base of the palm become inflamed after being aggravated. (image source: boldsky.com)

Preventive exercises for carpal tunnel syndrome

6.Which medical specialist to visit when you experience hand numbness.

Sufferers should visit a neurologist because they can assess by using a comprehensive neurological workup involving the brain, spinal cord and peripheral nerves. It is better to visit an orthopedist when the neurologist advises a visit to the orthopedist as necessary.

7.Summary

• Urgent medical attention must be sought when numbness is triggered by cerebral hemorrhage or cerebral infarction.
• Three critical factors should be examined when the symptom occurs: 1) Does the numbness appear suddenly; 2) Does the numbness occur only in one hand; 3) Does the numbness occur in both the thumb and little finger’s side of the hand?
• It is better to visit neurologists to get the brain, spinal cord and peripheral nerves examined so as to find an accurate cause of one’s hand numbness.