Paresthesia is the sensation of tingling or other abnormality (tingling, numbness…) in some part of the body. It can occur in the hands, for example..
This is quite common. But why does it happen and is it serious? It depends on the case.
In this article we will learn about nine possible causes of numbness in the hands.As we will see, sometimes there is an underlying disease to explain it.
My hands are falling asleep: what can it be due to?
Here is how, numbness or a tingling or tingling sensation in the hands (paresthesia) is a very common symptom.. Normally it is something momentary and has no major importance, although we must analyze in each case what possible causes originate this symptom (since sometimes it is a warning symptom of certain diseases).
Paresthesia in the hands appears due to an alteration in our sensitivity “by excess”; that is to say, we experience an abnormal sensation in a certain area of the body, without any stimulus that causes or explains it.
Paresthesia can appear in the context of an underlying medical disease (as a cause or consequence of it) or in isolation (in healthy people, who have simply maintained a posture for a long time, or other situations).
Let’s take a look at nine possible causes that could explain the numbness in the hands.
1. Remaining in the same posture
A very frequent cause of numbness in the hands is the maintenance of the same posture for a long time.
2. Having slept with the hand “pressed” on the pillow
Another possible cause of numbness in the hands is having slept with the hand under the pillow or between the legs, so that it was trapped. This can be during a daytime or nighttime nap.
3. Nutritional deficit
A nutritional deficit could also explain the sensation of numbness in the hands. Thus, this lack of certain nutrients could be the cause (for example deficits in vitamin B, vitamin B12, folic acid, etc.).
4. Compressed nerve
If a nerve in the hand or arm has been compressed, we may also experience this numbness in the hand or arm. There are different nerves that, when compressed, cause this numbness. Depending on the area, it will be one pathology or another. Let us look at the different possibilities:
4.1. Carpal tunnel syndrome.
This syndrome originates when the median nerve of the wrist is trapped. Specifically, the carpal tunnel is a channel that goes from the palm of the hand to the bones of the wrist; through it pass the tendons (so that we flex the fingers) and the median nerve.
When this syndrome appears, other symptoms appear that accompany it, beyond the numbness of the hand (or hands), such as: weakness of the wrist, difficulties to carry out some movements or to take objects, as well as pain in the wrist and the forearm (this pain, in addition, can increase during the night).
4.2. Herniated disc
We can also suffer from a herniated disc. To understand what it is, let’s imagine our spine; between each of its vertebrae we find a disc that protects them and acts as a shock absorber.
When the nucleus of some of these discs protrudes outwards (due to wear, injury, etc.), what we call disc herniation occurs. If the disc herniation occurs in the cervical spine, numbness (or tingling) may appear in the hands.
4.3. Guyon’s Canal Syndrome
Another syndrome that could be caused by a compressed nerve is the syndrome of the Guyon canal, which could also be the cause of our numbness of the hands. In this case, the nerve compression occurs in the elbow area (in a nerve called the ulnar nerve).
This syndrome is also accompanied by other symptoms, such as: pain in the elbow area (which may extend to the hand), muscle weakness in the hand, difficulties in performing the “pincer” gesture with the fingers, difficulties in flexing the fingers and the so-called claw hand (which is when the fingers remain bent and cannot be stretched).
5. Endocrine disease
Numbness or a tingling sensation in the hands may also indicate the possibility of an endocrine disease. Endocrine diseases have to do with our body’s hormone levels. We are going to see the two most frequent endocrine diseases that could be the cause of this abnormal sensation in the hands:
People who have diabetes are more likely to suffer some kind of nerve damage (especially when blood glucose control is altered or interrupted). Nerves influence the sensitivity of the extremities, which is why diabetics may experience numbness in the hands (or tingling, tingling, etc.) more frequently.
Thus, although this damage tends to affect the lower extremities in particular, it can also occur in the upper extremities. Specifically, a type of nerve damage caused by diabetes is called diabetic neuropathy. This affectation is suffered by about 50% of patients with diabetes (after 20 years with the disease).
Hypothyroidism is another endocrine disease that could also be the cause of hand numbness. This numbness can also affect the arms. In this way, hypothyroidism can lead to involvement of the nerve endings.
But what is hypothyroidism? It is an alteration in the secretion of thyroid hormone (related to stress); that is, the thyroid gland, responsible for secreting it, produces it in lower quantities than normal.
Hypothyroidism has an impact on the body’s normal metabolism and can also cause depressive symptoms, excessive tiredness, difficulty concentrating, feeling cold, weight gain, etc.
6. Circulatory or cardiovascular disorders
Another cause that may underlie numbness of the hands is a circulatory or cardiovascular disease. Normally, when there is an underlying circulatory disorder, problem or disease, the symptom of numbness of the hands is accompanied by other symptoms such as changes in the color of our skin.
Thus, in this case, the sensation of numbness in the hands is caused by an alteration in the blood flow of our vessels, which contract or dilate in an altered or unusual way.
On the other hand, when the cause is a cardiovascular problem or disease, the explanation lies in the fact that there is not a correct blood flow in some specific areas of the body (such as the hands), due to the accumulation of plaques in the arteries (atherosclerosis).