Causes of numbness in the finger

There are numerous causes for numbness in the finger. It is mostly a nervous disorder. It can occur along the entire course of the nerve from the brain to the finger.

Causes of numbness in the finger, which are located in the central nervous system – brain and spinal cord – are diseases such as multiple sclerosis or a stroke. A herniated disc can also press on the spinal cord or compress part of the spinal nerve in the area of the spine. In carpal tunnel syndrome, the nerve is only damaged at the level of the wrist.

Here too, numbness in the finger is the result. Other causes of nerve disorders are polyneuropathy or vitamin B 12 deficiency. Carpal tunnel syndrome causes the median nerve at the wrist to become constricted.

This damages the nerve fibres. Actually, the nerve should supply thumb, index finger and middle finger sensitively. However, if the nerve is pinched between the carpal bones and the carpal ligament above it, it can no longer perform this function.

A numbness in these fingers is the result.A nightly tingling of the affected fingers is also typical. In pronounced cases, the nerve must then be “freed” in a surgical procedure. Even a superficial cut can injure a skin nerve.

The sensitive nerve endings of the skin are relatively superficial. If they are injured, a numbness is the result. In most cases, however, this is only the case in the area of the cut.

In the case of deeper cuts, however, the entire nerve can be injured or, in the worst case, even severed. Then the numbness usually spreads over a whole finger or several fingers. A numbness in the finger is also conceivable in the context of a bruise on the hand.

The bruise causes tissue damage. Not only connective tissue and muscles are damaged, but also the nerves in this area. If nerve fibers are damaged by pressure, they can no longer transmit stimuli properly.

An area from which the brain no longer receives sensitive stimuli appears to the brain as “numb”. In most cases, however, the numbness improves again after a contusion. Often, at least the skin area becomes significantly smaller, because surrounding nerve fibers take over part of the innervation.

A numbness in the finger can always be a sign of multiple sclerosis, or in the case of a known MS disease, it can indicate a new attack. Multiple sclerosis is a chronic inflammatory disease that affects the central nervous system. The causes are ultimately not fully understood, but it is believed to be an autoimmune disease.

The symptoms are very diverse. In addition to visual disturbances and paralysis, they also include sensory disturbances such as feelings of numbness. You can find more about this clinical picture on our Multiple Sclerosis page.

A slipped disc in the area of the cervical spine can also cause a feeling of numbness. The nerves responsible for the sensitivity of the individual fingers originate from the plexus cervicalis. This originates from the spinal nerves of the spinal cord in the area of the cervical spine.

If the nerve fibers in this area are damaged, e.g. by a herniated disc, this leads to numbness in the area of the fingers or even the whole hand. Especially in combination with pain radiating from the neck, a numbness is typical for a herniated disc of the cervical spine. Polyneuropathy results in damage to the peripheral nervous system.

The nerves outside the brain and spinal cord are therefore affected. Typical symptoms are sensory disorders such as tingling or numbness. They mainly occur in the legs.

Numbness in the fingers is less frequently caused by polyneuropathy. However, it ultimately depends on which nerves are damaged by the disease. The causes of polyneuropathy are extremely diverse.

They range from alcohol, diabetes mellitus, to a vitamin B12 deficiency. Vitamin B12 is the most important vitamin for a healthy nervous system. If the body lacks vitamin B12, disturbances in the nervous system can occur.

Vitamin B12 is important for a stable myelin sheath. This is a fat-rich layer of myelin that surrounds a nerve fiber. Only with an intact myelin sheath can the nerve perform its function, the transmission of stimuli, without error. Vitamin B12 deficiency therefore also leads to numbness and painful tingling.