Definition
The collective term “paralysis of the leg” covers all clinical pictures in which the leg is no longer capable of executing the physiologically possible movements willingly or with adequate strength. This can be caused by diseases of the muscles themselves, but also by loss of function or malfunction of the nerves supplying the muscles. The extent of the paralysis in the leg varies depending on the cause, whereby a general distinction is made between complete paralysis of the leg muscles (plegie) and paralysis in which movement is possible in a weakened state (paresis). Monoparesis or monoplegia of the leg is the situation when only one leg is affected by the paralysis, whereas paraparesis or paraplegia of the legs describes the paralysis of both legs.
Causes
Paralysis of the leg can basically occur on three levels in the body. The cause can be located in the nervous system, in the muscle itself or at the transition between the nerve and the muscle. If the nervous system is responsible for the paralysis, several triggers can lead to the symptoms.
Centrally, i.e. in the brain, a stroke is often the cause of the paralysis. Likewise, an injury to the spinal cord in the form of paraplegia can lead to the same disorder. If the damage to the nervous system lies outside the brain and spinal cord (central nervous system), it is called peripheral damage.
In this case, a nerve can be injured, for example by trauma, or it can be compressed by a herniated disc (prolapse), so that it can no longer perform its function, namely to make the muscle contract. If the cause of the paralysis in the leg lies in the muscles themselves, it is usually due to hereditary muscular diseases, in which errors in the structure of the individual muscle cells mean that the muscles cannot perform their function physiologically. This is the case with muscular dystrophies, for example.
If the signal transmission from the nerves to the muscles is disturbed, this is referred to as disturbance of the neuromuscular transition. These diseases are rather rare and usually occur in the context of hereditary diseases. Finally, paralysis in the leg can also be psychologically caused and has been observed, for example, in the psychiatric clinical picture of the dissociative disorder.
In the context of a herniated disc in the lumbar spine, paralysis in the leg can sometimes occur. This is due to the fact that the nerves responsible for the legs in the lumbar spine area exit the spinal cord and can therefore be compressed by a herniated disc in this area. In this way, the lifting of the big toe may be restricted or, in the case of a more extensive herniated disc, entire muscle groups may be paralysed.
Symptoms of paralysis are usually perceived as more threatening than sensory disturbances (tingling, numbness) and therefore tend to require immediate medical attention. This is also a good thing: With quick (usually surgical) treatment, an immediate, considerable improvement of the paralysis symptoms can often be achieved. The most frequent herniated disc occurs in the area of the lumbar spine between the fourth and fifth vertebrae.
If the corresponding nerves are affected, one speaks of the L4 syndrome or, in the case of deeper localization of the damage, of the L5 syndrome. In L4 syndrome, in addition to pain in the anterior leg region when the nerve fibers responsible for motor function are damaged, a restriction in the extension of the knee and flexion of the hip is also to be expected. In the L5 syndrome, the motor function of the foot lifting is affected, which means that the foot and big toe can no longer be lifted.
This results in a conspicuous gait pattern when walking, as the affected person tries to compensate for the lack of foot lift by bending the knee and hip more strongly. andIn multiple sclerosis (MS), the nerve sheaths that surround the nerves like a protective and insulating sheath are damaged by an inflammatory process, which impairs the function of the entire nerve. Consequently, paralysis is one of the symptoms triggered by MS.
Since MS is mostly a relapsing-remitting disease, the paralysis manifests itself in many patients as an overnight insecurity in walking. An immediate medical examination can confirm the suspicion of an MS relapse.Cortisone shock therapy can then reduce the duration and intensity of the relapse and also improve the long-term prognosis of MS. Guillain-Barré syndrome (GBS) is an inflammation of several nerve roots. The mechanisms of the disease are not yet fully understood, but it can be assumed that it is an autoimmune disease against the membranes of the nerve cells.
In many cases, a recent bacterial or viral infection can be assumed to be the trigger of the autoimmune reaction. GBS is characterized by ascending paralysis, i.e. paralysis that starts from the legs and spreads upwards. These typically occur symmetrically, i.e. on both sides.
It is obvious that paralysis in the leg does not occur after injections into the shoulder, but only after injections into the gluteal muscle. But even in the latter case, such symptoms are the absolute exception. The paralysis symptoms are then due to the fact that the injection has hit and damaged a nerve that is responsible for the motor supply to the leg muscles.
Frequently, the paralysis is accompanied by an emotional disturbance in the form of numbness. If the paralysis symptoms are actually due to the injection, they occur immediately after the vaccination. A later occurrence of paralysis cannot be explained by the injection and should be examined for other possible causes.
Symptoms of paralysis in the leg following surgery are not usually too serious if a so-called spinal anaesthesia (anaesthesia of the spinal cord) has been administered, as the anaesthesia of the legs does not disappear abruptly after the operation. Furthermore, swellings as a result of an operation on the leg (e.g. joint surgery) can also considerably restrict the mobility of the leg and thus simulate paralysis. However, special attention should be paid to the possible occurrence of paralysis in the leg after back operations, especially in the lumbar spine area.
This is the area where the nerves responsible for supplying the legs emerge from the spinal cord. Consequently, these nerves are particularly at risk during operations in the lumbar spine area. However, even in such operations, paralysis is relatively rare and if it does occur, it usually improves considerably within a few days.
Panic attacks often include not only the eponymous sudden feeling of fear, but also physical symptoms such as palpitations, sweating, difficulty swallowing, shortness of breath or even paralysis. The latter are often perceived by those affected as particularly alarming and can thus prolong the duration of the panic attack. In this case, it is important to inform the affected persons in advance that such paralysis symptoms are to be interpreted as a manifestation of the panic attack and usually disappear again within minutes.
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