When hands, feet, arms and legs tingle and go numb, the vernacular speaks of limbs falling asleep. The unpleasant sensory disturbance is usually only temporary. However, there are also conditions in which these insensations occur frequently or are even permanent. If this is the case, the affected person should immediately consult a specialist.
What are limbs that fall asleep?
Usually, limbs that fall asleep are caused by a short-term disturbance of the blood supply, for example, when lying or sitting in certain positions. If limbs tingle or even go numb so that the affected person can no longer feel them, it is usually a temporary disturbance of the conduction system:
A nerve is pinched off by a position when sitting or lying down, or by remaining in one and the same posture for too long. This tells the brain via the strange body sensations that it is cut off from the oxygen and nutrient supply. In cases of hands and feet falling asleep, usually only the peripheral nervous system is affected.
Causes
If the limbs that have fallen asleep do not normalize despite changes in position and other measures, or if they recur frequently, a serious chronic condition underlies them. If the unpleasant sensations in the toes and fingers occur along with hemiplegia, inability to pick up an object, and speech problems, emergency medical attention should be sought as soon as possible because the condition is probably a stroke. In polyneuropathy (PNP), pinched nerves suffer permanent damage: the peripheral nerves become inflamed immediately. Causes of genetic polyneuropathy can include diabetes mellitus, infections, alcohol dependence, autoimmune diseases, certain medications, chemotherapy, and vitamin deficiencies. In patients with polyneuropathy, pressure on the nerves quickly causes damage that is slow to heal. They have not only, the also healthy people well known, asleep limbs, but also a disturbed pain sensation. Even simple injuries cause burning and stabbing pain in fingers and toes. The insensations first appear on the feet, then on the hands and even on the lower leg. If the polyneuropathy patient is also diabetic, he usually feels an increased sensation of pain at the beginning of the disease, which, however, weakens in the course of time so that he hardly feels anything anymore. Combined with insecurity when walking and standing, accidents occur more frequently. Since the diabetic no longer notices the injuries to the foot, the so-called “diabetic foot” with open wounds develops. A slipped disc or spinal damage can also be the cause of limbs that fall asleep. In such a case, the tingling or numb feeling is permanent. In addition, the unpleasant sensations in the toes and fingers occur in connection with multiple sclerosis, angina pectoris, certain poisonings and vitamin B12 deficiency. The insidious thing about this deficiency disease is that it is not detectable in blood work and – if not treated in time – can lead to paralysis, impaired movement coordination, gait unsteadiness, memory impairment, depression and confusion. In restless legs syndrome, as the name suggests, only the legs are affected. It manifests itself when the body is at rest in the form of twitching of the feet, tingling of the toes, and an urge to move. Carpal tunnel syndrome occurs when the median nerve (carpal nerve), which causes the sensation, is pinched in the carpal tunnel on the inside of the hand. If it does not find a better position in it, it causes frequent tingling and numbness. It is relieved of pressure by a specially made splint. If there is still no improvement in the symptoms, surgical intervention is required.
Diseases with this symptom
- Stroke
- Alcohol addiction
- Lyme disease
- Diabetic foot syndrome
- Herniated disc
- Restless Legs Syndrome
- Polyneuropathy
- Vitamin deficiency
- HIV infection
- Arteriosclerosis
- Multiple sclerosis
- Vitamin B12
- Diabetes mellitus
- Chemotherapy
- Drug allergy
- Diphtheria
- Angina pectoris
- Carpal tunnel syndrome
Diagnosis and course
In some cases, the unusual tingling, which can also occur bilaterally and at night, is still accompanied by severe pain and decreasing muscle strength. If the patient also notices impaired coordination of movement and unsteady gait behavior, it is necessary to see the doctor. The same applies if the unbearable sensations do not disappear despite a change of position and the condition occurs frequently and regularly. The first contact persons are then neurologists and/or orthopedists. If the polyneuropathy also affects the autonomic nervous system, the nerve signals are no longer transmitted to the brain: Even cardiac arrhythmias as well as bladder and bowel emptying disorders can be the result. People with polyneuropathy have reduced nerve conduction velocity, little/no touch sensation, and little/no sensation of cold, heat, or vibration.
Complications
Limb numbness is usually harmless, but can sometimes result in serious complications. If the numbness in the limbs persists over a long period of time or recurs, there may initially be a reduction in muscle mass in the affected region of the body, accompanied by a reduction in motor skills. Hands that have fallen asleep, as is the case with carpal tunnel syndrome or pinched nerves, for example, can be moved less and less over time as the nerve signals that are conducted to the hand diminish. This is accompanied by the typical tingling sensation in the limbs. If the symptoms occur as a result of a herniated disc, the complaints can initially be expected to intensify: there is severe pain, muscle tension and, in the further course, incorrect loading of the affected joints. In the worst case, the complaints intensify and persist after the cause has been eliminated. Nerve damage as a cause is particularly problematic, because the symptoms mentioned lead to further damage to the muscle fibers, muscle paralysis and so-called root death, i.e. irreparable damage to the nerves. Falling asleep limbs impair the perception of pain in the affected body region and thus lead to bedsores, pressure sores and abscesses, especially in bedridden people, often accompanied by severe pain, circulatory disorders and chronic nerve damage in the affected limbs.
When should you see a doctor?
Sitting in an unchanged position for a long time, lying awkwardly, and crossing or bending legs can cause limbs to fall asleep. Remedy is usually simple: a change in posture or, even better, exercise. The tingling sensation that soon follows signals the end of this haunting. The cause of limbs falling asleep is the entrapment of nerves – not blood vessels, as is often assumed. Despite this intrinsically harmless cause of limbs falling asleep, this condition should be avoided if possible. Permanent nerve damage can occur if limbs that fall asleep are provoked repeatedly. If falling asleep limbs occur more frequently and the numbness does not resolve completely, a visit to the doctor is absolutely necessary. Behind the phenomenon may be a disease that requires treatment. Limb falling asleep may be caused by diabetes mellitus or multiple sclerosis. A fallen asleep arm can be caused by the not so rare carpal tunnel syndrome, in which the carpal nerve is pinched in the area of the palm. An unbalanced diet and extreme alcohol consumption are also possible triggers of numb limbs. Numb limbs are further a concomitant of chemotherapy. Occasionally, limbs that fall asleep can also be caused by a damaged spine. Especially in case of a herniated disc, nerves responsible for sensations in the limbs are pinched. If the sensation of limbs falling asleep is even accompanied by coordination problems, the emergency physician should be called immediately.
Treatment and therapy
To end the condition, the person can change position or massage the affected body part to restore good blood flow. However, if the person remains in the position that is damaging to the nerve, extreme numbness will result, and if the position is prolonged, real nerve damage will occur.If cold is the culprit, simple measures such as a hot water bottle, blanket or warm compresses help to quickly eliminate the tingling or numbness. Psychological stress can trigger anxiety, which in turn, due to the associated shallow breathing, affects the blood circulation in such a way that the limbs can no longer be felt. In this case, calming coaxing and conscious control of breathing helps. To prevent the condition from recurring, relaxation exercises and breathing training are recommended. If the underlying disease is treated, the nerve symptoms will also decrease. Otherwise, tablets for nerve pain help.
Outlook and prognosis
Falling asleep limbs should be quite familiar to most of us. Usually, a nerve is pinched, which is harmless: as soon as you have moved to a more favorable position, the numbness disappears quite quickly. This process can be accelerated by careful gymnastic exercises or tensing and relaxing the muscles in the corresponding limbs. However, numb limbs can also be caused by very serious diseases. In these cases, the prognosis is worse. Multiple sclerosis (MS), for example, is essentially incurable. However, research is progressing rapidly as far as the treatability of this insidious disease is concerned. So if you see a doctor in time, you can live with the disease undisturbed for a long time. In the case of diabetes, limbs that fall asleep often indicate that the disease is changing and the patient needs to be readjusted. Again, first and foremost, the doctor’s instructions regarding diet and general lifestyle must be followed, otherwise relief is not possible. Falling asleep limbs also often have a clear cause: alcohol. Excessive alcohol consumption over a long period of time leads to corresponding symptoms, which usually disappear when patients change their lifestyle. This is not easy, but not impossible either. The doctor can help here, as can various therapy facilities and self-help groups. The same applies to the abuse of medications or even drugs, which can also result in such symptoms.
Prevention
The unpleasant sensory stimuli have the function of telling the person sitting incorrectly or lying uncomfortably that his posture is unhealthy and that he should change it. In other cases, the short-lived insensations can also be triggered by great cold, mild shock, and severe psychological stress. Therefore, it is important to pay attention to a healthy posture and to keep the body healthy as a whole and not to over- or understrain it.
This is what you can do yourself
In most cases, limbs falling asleep is not a harmful medical complication, which is why this symptom does not need to be treated directly. If the limbs have fallen asleep, they must first be supplied with blood before they can be actively used. During this blood circulation, the person feels a slight tingling sensation, which is perfectly normal. If the limbs falling asleep occur more often, it is often due to poor positioning of the limbs. This includes sitting too long or in an unhealthy position. The patient should move more and exercise more in general. It is also helpful to keep the limbs in warm water. However, if the tingling occurs often, this indicates a pinched nerve. This should not be treated by home remedies, but directly by a doctor. A pinched nerve may indicate a herniated disc and should be examined immediately. In most cases, changing the sitting posture or massaging the limbs that have fallen asleep will help. If the tingling is caused by cold, a hot water bottle will help. It can also happen that anxiety and stress trigger the limbs falling asleep. In these situations, breathing exercises help.