Causes of numbness in the hands and feet include temporary and disease-related causes.
Numbness that has an immediate cause (for example, putting pressure on the hand or foot for a while) or numbness that subsides in a day or two is usually not a disease. If the numbness does not subside or becomes stronger, a disease is suspected.
Don't leave them unattended, as some require immediate medical attention. Here, we will discuss the diseases that cause numbness in the limbs.
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A disease suspected of numbness in the limbs
There are three main causes of numbness in the limbs: brain diseases, spinal cord diseases, and other diseases.
brain disease
Since the brain plays a role in controlling the whole body, movement disorders including numbness occur due to lesions (changes due to disease).Typical examples include cerebral infarction, brain tumor, cerebral hemorrhage, cerebral contusion, and central hypothyroidism.
Cerebral infarction, brain tumor, cerebral hemorrhage, and cerebral contusion are usuallyNumbness occurs in the extremity opposite the affected area (right or left hemisphere).It can also appear on one half of the face.
Numbness does not go away on its own.
In central hypothyroidism, if there is some kind of abnormality in the pituitary gland in the brain, the secretion of thyroid-stimulating hormone from the pituitary gland decreases, and the secretion of hormones from the thyroid gland also decreases.
Thyroid hormone is involved in metabolism, so when its secretion decreases, limbs tend to swell.
As a result, the nerves in the hands and feet are compressed, causing numbness. I have "Carpal Tunnel Syndrome" in my hands, and my thumb, index finger, middle finger, and half of my ring finger are all numb. In my feet, I have "anterior tarsal tunnel syndrome," which causes numbness at the base of my thumb and forefinger. The hands and feet are usually bilateral and tend to become more numb when the limbs are overused. ①
All of the above-mentioned illnesses are urgent, so immediately seek medical attention or call an ambulance.
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disease of the spinal cord
Because the spinal cord is the nerve that passes commands from the brain to the limbs, numbness occurs due to lesions in the spinal cord and the bones and ligaments surrounding the spinal cord.
Typical examples include spinal cord tumors, cervical and lumbar disc herniation, ossification of the posterior longitudinal ligament, and spinal canal stenosis.
Spinal cord tumors cause numbness in one or more limbs because they grow in the spinal cord or in the spinal canal that surrounds the spinal cord. Numbness is often unrelenting.
In cervical and lumbar disc herniation, posterior longitudinal ligament ossification, and spinal canal stenosis, the intervertebral discs surrounding the spinal cord, the posterior longitudinal ligament, and the spinal canal become deformed, compressing the spinal cord and causing numbness in the limbs or either.
It is characterized by the appearance of numbness changing depending on the posture. Leaning backwards or sitting puts pressure on the spinal cord, which aggravates numbness. On the contrary, when you are standing upside down or looking straight ahead, the pressure is relieved and the numbness is relieved.
With respect to laterality, in all diseases of the spinal cord, depending on the location and degree of compression on the spinal cord, it may appear in one side or both sides.
The spinal cord also contains nerves that issue instructions for excretion. Seek medical attention immediately.
other illness
In other diseases, numbness is caused by vascular, metabolic or immune abnormalities that affect the peripheral nerves.
Typical examples include diabetes, hypoparathyroidism, thoracic outlet syndrome, arteriosclerosis obliterans, and Guillain-Barre syndrome.
In diabetes, substances that inhibit the function of nerve cells accumulate in the nerves, and the "blood becomes muddy" and blood flow deteriorates, preventing oxygen and nutrients from reaching the extremities. As a result, you will feel numbness in the fingertips of both hands and feet.
In thoracic outlet syndrome, there is a lot of arm movement, and in women with sloping shoulders, the blood vessels and nerves from the chest to the shoulder that connect to the upper limbs are compressed for a long time, causing numbness on the little finger side from the elbow. Numbness may appear in one side or both sides. ②No leg numbness.
In hypoparathyroidism, when the parathyroid gland is also removed or damaged during thyroid surgery, the adjustment of calcium concentration, which is the function of the parathyroid gland, is disrupted, resulting in numbness in the hands and around the mouth.
In arteriosclerosis obliterans, arteriosclerosis of the blood vessels that run through the lower extremities causes numbness from the toes due to lack of oxygen and nutrients. Many feel numbness on both sides. No hand numbness.
In Guillain-Barré syndrome, a viral infection causes the autoimmune function to malfunction and attack the own nerves, resulting in numbness in the hands and feet.
One to two weeks after having a cold or diarrhea, numbness and weakness in the limbs on both sides suddenly occur, sometimes accompanied by symptoms such as inability to move facial muscles.③
Each of the diseases mentioned above has a different degree of urgency. As arteriosclerosis obliterans progresses, lower extremity amputation may be required. Guillain-Barré syndrome can also be life-threatening if it affects the muscles involved in breathing. Seek medical attention immediately or call an ambulance. For other diseases, receive instructions and treatment from your doctor to prevent numbness and the deterioration of the underlying disease.
reference)
③Sudden symmetrical weakness and numbness in limbs – Hyogo Medical Association (med.or.jp)
summary
This time, I talked about the disease that causes numbness in the limbs.
The location and appearance of numbness are different for each disease. In any case, visit a medical institution to prevent numbness and deterioration of the underlying disease. For urgent matters, please call an ambulance as soon as possible.
Focus on changes in your body and aim for a better life.
Supervision: Dr. Yasushi Tsuda