The term median nerve palsy is the short name for a paralysis of the median nerve. This nerve is one of the three main nerves in the arm. With a median nerve palsy, the flexion of the hand and fingers as well as the function of the thumb is restricted.
What is median nerve palsy?
Median paralysis occurs when the median nerve is damaged at any point in such a way that muscles dependent on it no longer receive nerve impulses. See AbbreviationFinder for abbreviations related to Median Paralysis.
The type and extent of the paralysis depend on the level at which the nerve is damaged. To understand median nerve palsy, it is important to have a basic understanding of the anatomy of the nerve. The median nerve (the “middle nerve”) emerges from the arm nerve network (brachial plexus) in the armpit and runs in a channel medial to the biceps brachii muscle (colloquially “biceps”) to the crook of the elbow.
There it enters the front of the forearm between the two heads of the pronator teres muscle and innervates most of the flexor muscles here. Along with the tendons of these flexor muscles, the median nerve passes through the carpal tunnel to the hand. In the palm of the hand, it branches into sensory terminal branches and motor branches for the thumb muscles.
A rough distinction is made between a proximal (near the trunk) median nerve palsy with a lesion in the elbow area and a distal (away from the trunk) median nerve palsy, in which the nerve at the wrist is damaged.
The most common cause of median nerve paralysis is damage from chronic pressure in the carpal tunnel (known as carpal tunnel syndrome). The carpal tunnel is a canal formed by the carpal bones and covered by ligamentous structures. In some people, the carpal tunnel is naturally narrow. If additional pathological masses occur, e.g. B. by tendonitis, the median nerve is chronically compressed.
In addition to permanent compression, external force can cause paralysis of the median nerve. Proximal median paralysis is often based on fractures or dislocations (dislocations) of the elbow joint. Distal median nerve palsies can result from lacerated wrists or fractures of the carpal bones.
Typical Symptoms & Signs
- Paralysis of fingers and thumb
- Restricted movement of the fingers
- emotional disturbances
Diagnosis & History
A median paralysis can usually be diagnosed on the basis of the characteristic motor and sensory deficits. In the case of a paralysis of the proximal median nerve, a “swear hand” occurs when you try to clench your fist: only the ring finger and little finger can still be bent.
The “bottle sign” is positive, ie a bottle can no longer be gripped properly due to the failure of the thumb muscles. Pronation (inward turning) of the hand is only partially successful. Numbness occurs on the skin of the palm of the hand from the thumb to halfway down the ring finger. With distal median nerve palsy, the long hand flexors on the forearm still function, so there is no swear hand.
The “bottle sign” is also positive here. The fingertips of the index and middle fingers are numb. In addition to the comprehensive neurological examination, an anamnesis helps with the diagnosis: previous injuries to the arm or a known carpal tunnel syndrome provide clues. The diagnosis of median nerve paralysis can be supported by measuring electrical muscle activity ( electromyography ).
The paralysis of the median nerves primarily leads to various disorders of sensitivity or paralysis, which mainly occur in the fingers and hands. The thumb is also affected by median nerve paralysis in most cases. The fingers can only be moved to a limited extent, so that the patient has considerable restrictions in everyday life.
Certain activities or work can no longer be carried out easily due to the paralysis of the median nerve, so that the quality of life is significantly reduced. Various sensory disturbances also occur, which continue to impair everyday life. The further course of the disease usually also depends on its cause.
In most cases, however, there are no particular complications unless the injury is particularly serious. Life expectancy is usually not limited or reduced by paralysis of the median nerve. Treatment of this paralysis is usually not necessary. In most cases, the symptoms will go away on their own over time. Interventions are only necessary in rare cases to alleviate the symptoms. There are no further complications either.
When should you go to the doctor?
If symptoms of the musculoskeletal system appear, this is a sign of an existing health irregularity. In the case of median nerve paralysis, there are limitations in mobility in the areas of the arms and hands. If the person concerned can no longer move their arms as usual, they need a doctor. The impairments can start from the shoulder along the arm to the fingers and must be treated medically. If the existing symptoms increase in intensity or extent, a doctor should be consulted immediately. In the event of a loss of the usual level of physical performance or irritability, a visit to a doctor is advisable.
If the gripping functions can no longer be performed, a medical clarification of the symptoms is necessary. As soon as everyday activities can no longer be carried out, the person concerned needs medical care. In an extensive medical examination and various tests, the cause of the existing malfunctions must be determined so that a diagnosis can be made. If there is a perception disorder on the skin on the arm or hands, a doctor is also needed. In the event of an irregularity through touch, irritation of the sensitivity, sensory disturbances, a tingling sensation on the skin or numbness, a doctor should be consulted.
Treatment & Therapy
The treatment of a median nerve palsy depends on the cause of the damage. Paralysis caused by pressure damage often resolves on its own. If the nerve is severed as a result of fractures or cuts, surgical reconstruction can be attempted.
If the median nerve paralysis occurs due to compression in the carpal tunnel, either conservative therapy (e.g. with medication and/or special medical technology) or an operation is carried out, depending on the severity. The aim of the operation is permanent pressure relief, for example by opening the entire carpal tunnel or by splitting the tendon. Physiotherapy is usually required for follow-up treatment.
Outlook & Forecast
In most cases, patients with median nerve palsy have a favorable prognosis. Due to the self-healing powers of the organism, there is often an automatic regression of the symptoms until recovery finally occurs. The disease has healed within a few weeks or months. Nerve activity regenerates after a short time, particularly in the case of pressure damage, minor injuries or severe physical strain on the organism. The paralysis is temporary and resolves completely.
In the future, however, changes in lifestyle should be made so that the functional activity of the nerve fibers is not irreparably damaged. If complaints and health irregularities occur again in the course of life, the prognosis is also favorable for the causes mentioned. In the case of fractures, a surgical intervention takes place in a large number of cases. This is associated with risks, but is usually completed in a routine process without any further disruptions.
Overall, median nerve paralysis can often be cured by the administration of medicines and self-help measures. In addition, physiotherapeutic exercises are used to support the healing process and avoid secondary diseases. The person concerned can independently contribute something to improve the situation by using the physiotherapeutic training units learned outside of the sessions.
There is no prevention against traumatic median nerve paralysis. For carpal tunnel syndrome, on the other hand, there are risk factors that can be influenced.
People who are at risk include people who have lost a lot of weight but have not strengthened their muscles and therefore have slack connective tissue. Patients with kidney damage or diabetes mellitus are also at higher risk due to the risk of tissue swelling. The first symptoms of carpal tunnel syndrome are discomfort and pain on the thumb side of the palm, which occurs particularly at night or after mechanical stress on the wrist.
Such signs should be taken seriously and evaluated by a physician to treat any nerve compression before complete median nerve palsy develops.
A paralysis of the median nerve is usually associated with various complaints, all of which can usually have a very negative effect on the quality of life of the person concerned. Therefore, the aftercare focuses on counteracting a further deterioration of the symptoms. With the help of physiotherapy, the damaged fingers are strengthened muscularly. Because those affected have to get by with restrictions in movement in everyday life.
Many of those affected are therefore dependent on the help and support of friends and their own family in order to be able to cope with everyday life. The fingers themselves can no longer be moved properly. Emotional disorders also occur on the fingers or even on the hand.
Touches or temperatures can no longer be correctly assessed, which can also lead to complaints in the everyday life of the person concerned. The disease itself can be treated well in many cases. It does not have a negative effect on the life expectancy of the affected person and does not usually reduce it.
You can do that yourself
The measures that can be taken in the event of median nerve paralysis depend on the cause and severity of the damage. Slight signs of paralysis, for example caused by a bruise or sprain on the arm, usually disappear on their own.
Surgery is required for severe injuries. Beforehand, an examination plan must be drawn up together with the doctor, in which the control examinations and other details are recorded. Shortly before the procedure, the person concerned should no longer strain the muscle and otherwise follow the instructions of the doctor responsible. The recovery can then be supported by the typical aftercare measures, i.e. rest and cooling, but also by light stretching exercises.
In general, physiotherapy should be carried out daily with median nerve paralysis so that the paralysis recedes completely as quickly as possible. If a motor replacement operation is carried out, the donor muscle must be strengthened in a targeted manner, for example through physiotherapy or through massages and aids. Physiotherapy exercises are usually started after four to five weeks after replacement surgery. What other measures the person concerned can take to promote healing can only be answered by the responsible specialist.