What is Numbness?
Sensitivity means sense of human touch. Numerous nerve endings, receptors, sensors throughout the body and sensory organs such as eyes, ears and skin are sense sensory stimuli which transmit them to the central nervous system (CNS).
Thus, we can perceive mechanical sensations (such as pressure, vibrations), temperature sensations (thermoception), pain perception (nociception) and many more.
Sensory disturbances can be divided into as tactile hypoesthesia and thermal hypoesthesia. Tactile hypoesthesia reduces the sensation and sensation of pressure and thermal hypoesthesia causes to feel cold and heat worse than normal. Complete sensory loss is called anesthesia.
Numbness usually occurs in the limbs, arms, legs and less often on the face. Numbness can occur in both arms or in both legs, or only in an arm or a leg, or in half side. Numbness can also affect individual fingers or toes. There can be simultaneous pains that spread throughout the body and there can be balance problems, speech problems or vision problems. If the numbness goes away on its own, a typical tingling sensation may follow.
If numbness occurs suddenly and continues for long time, individuals should consult their doctor to clarify the causes of numbness and to initiate an appropriate treatment.
What Causes Numbness?
Numbness can have different causes. It may be an indication of lack of blood flow to the limb or a nerve injury. Numbness usually affects the hands (especially the toes), foot, legs and the arms. But, numbness can reach any part of the body depending on the reason that causes it.
Temporary numbness often occurs when a nerve is affected by pressure from an uncomfortable posture. This is the case when resting the arm on the chair or lying down on the elbow for a long time.
Numbness is a characteristic symptom of neuropathy. An intervertebral disc herniation which presses on a nerve root may also produce a numbness. Diseases of the sciatic nerve which extends from the lumbar vertebrae to the knee are common cause of numbness in the leg. Also spinal stenosis which occurs when there is an abnormal development of the spine, for example: improper development of bones that cause scoliosis or by bone degeneration associated with age.
In general, numbness is not usually severe, although in some cases it may be a symptom of a tumor. Numbness can also be caused by blood vessels when they are larger dimension than usual size. Tumors can be localized anywhere in the body, but spinal tumors which are located in spinal cord are involved with numbness.
Some diseases, such as hypothyroidism, epilepsy, diabetes, migraine and multiple sclerosis also occur with numbness of the extremities.
Certain drugs and treatments, such as chemotherapy and radiotherapy have their side effects with numbness. Lead poisoning, alcohol and tobacco can cause numbness in the body.
An unbalanced diet with inadequate levels of calcium, sodium, potassium and vitamin B12 shortage cause numbness in the extremities.
Other causes of numbness may be:
- Skin burns
- Nerve injury due to accidents
- Carpal tunnel syndrome
- Herpes zoster
- Hypoperfusion (ischemia)
- Bite or sting (tick, insect, spider …)
- Raynaud’s Syndrome
If it is a sensation of numbness, as a first step of the diagnosis, it is important for the doctor to know exactly when the sensation of numbness first occurred. It is also crucial to know for the doctor if numbness first time happened after a particular crash such as an “unfortunate” movement or after an accident. Likewise, existing and known diseases are an important starting point to provide the physician with an initial indication of the cause of numbness.
During a physical examination, the doctor will try to delimit the area affected by numbness as accurately as possible. This can help you locate possible nerve damage. Own reflexes are checked to determine neurological deficits: hearing, sight, sense of balance and the state of consciousness.
If numbness lasts for a prolonged period, you must consult your doctor immediately. Go to hospital urgently, if you have any symptoms at the following:
- Difficulty moving or walking
- Sphincter control is lost
- There are visual disturbances or difficulty speaking normally
- Agitation or confusion of thought
- Loss of consciousness
- Numbness linked to a rash on the skin
- Dizziness or spasms
Depending on the cause under suspicion, additional examinations may be performed including computed tomography, magnetic resonance imaging, Doppler ultrasonography of the vessels, electromyography (EMG), x-rays and blood tests.
How to Treat Numbness
Treatment of numbness is always directed at the cause of the problem which can be varied greatly depending on individuals. A temporary numbness due to an “inadequate” position of the body often disappears by itself shortly after changing position or taking measures to improve the position.
As in the case of carpal tunnel syndrome where the sensation of numbness can be relieved with some anti-inflammatory drug such as ibuprofen, prescribed by the doctor.
Prolonged sedentary lifestyle causes numbness and many other problems. So, it is advisable to maintain a routine of exercises and stretching to improve blood circulation. Doing moderate exercise on a regular basis, such as yoga can also help against the feeling of numbness by favoring better blood circulation. In general, walking or any other athletic activity that acts against the sedentarism can help to overcome the sensation of numbness when it has been provoked by lack of movement.
Congenital neuropathies still can not be treated and diabetic neuropathy requires an optimal balance of blood sugar.