What Causes Numb Hands?

In this article we explain everything you need to know about numb hands and which cause is most common. Numb hands can be a frequent and uncomfortable feeling. The affected body part will become stiff or inflexible and you will likely feel like pins and needles.

It is often a reason to go to the doctor. The problem is that its origins are very varied and as such it can be complex to make a correct diagnosis.

What Happens When You Have Numb Hands?

Numb hands, as we have explained, is a change in sensitivity and movement in this part of the body. The sense of touch is distorted and it is not easy to move your fingers.

In many cases, in addition to the pinprick sensation, you may experience a burning or tingling sensation. Depending on the cause of the numbness, it may be in the fingers only, on one side, or in both.

One reason for numb hands can be the cold, which is quite common and usually has no lasting effects. However, according to a study conducted in Sweden , the most common pathology is carpal tunnel syndrome. This study explains that 1 in 5 people who experience this symptom are likely to suffer from this syndrome.

Cause of numb hands

Numb hands can be caused by many different reasons. A systematic pathology occurring in the upper limbs, or an injury to the nerves (for example, due to compression or damage), can lead to feeling this sensation.

However, a change in the brain or spinal cord can also occur as both are organs that coordinate sensation and mobility. That said, these injuries are usually more serious and show obvious or debilitating symptoms.

Metabolic or infectious diseases, as well as certain medical treatments, can lead to this situation. In the following sections of this article, we will explain in detail the main causes of this problem.

Brain and Nervous System Disorders

Any pathology that affects the nervous system and, in particular, damages the area related to the hands, can cause numbness. The Guillain-Baré syndrome for example (Spanish link). It is a condition in which the immune system attacks nerve cells.

According to a study published in the Postgraduate Journal of the Vla Cátedra de Medicina (Spanish link), numb hands are one of the diagnosable symptoms. Cervical spondylosis is also related to this, as it involves the wearing away of the intervertebral discs, where the nerves going to the extremities begin their journey.

Damaged by trauma or overuse

In this category we find carpal tunnel syndrome as the main cause. It is where the median nerve is compressed. A nerve that goes from the forearm to the fingers. This causes wrist pain, numbness, cramps and tingling.

Although this is the main cause, a number of other illnesses and injuries also lead to this feeling. The cubital tunnel syndrome for example (Spanish link). Here another nerve is compressed. The same happens when the brachial plexus is damaged after an accident.

The latter mechanism ends in a common path that is tightened or compressed. The brain misinterprets the signals coming from the compressed neurons and sends signals of tingling, pain and even paralysis to the hands.

Infectious diseases that cause numb hands

Lyme disease is an infection that you can get through the bite of certain ticks. According to the Centers for the Control and Prevention of Illnesses, if you don’t get treatment on time, you’re likely to end up with numb hands.

Another infectious pathology that can cause this symptom is syphilis. As with the previous illness, if you delay your treatment, it damages the nervous system as it develops.

Chronic illness

Many conditions can result in nerve damage. The result of such conditions is changes in sensation and mobility. Diabetes is one of the most important and common. It causes diabetic neuropathy that is directly related to numb hands, according to the University of California.

Alcohol consumption, amyloidosis and multiple sclerosis are also chronic processes that affect the upper limbs. While cancer is not the most typical condition to cause this, chemotherapy uses a combination of drugs that can cause adverse side effects.

Another possible cause of numb hands

An anecdotal fact puts the blame on the ganglia (Spanish link). These are cysts that often appear on the joints, such as the wrist. If they grow too much or press on a nearby nerve, they lead to numbness.

On the other hand , vasculitis restricts blood flow to the palm and fingers. Vasculitis causes inflammation of the artery walls (Spanish link) which then reduce their capacity. This means that less oxygen reaches the tissues, causing damage.

When should we go to a doctor?

If you notice numbness in your hands, then you should see a doctor. They should be able to perform a physical exam and additional tests to make a diagnosis.

As we have seen, the causes are varied and there may be no clear solution at first. Different approaches may be needed to clarify which condition you have. Don’t worry though, most causes have a solution.