Classic nerve block refers to the impairment, or complete block, of peripheral nerves in their function as conductors of motor, sensory, and autonomic impulses. Permanent or facultative impairment of nerves can be triggered by mechanical pressure or traction stimuli or by chemical stimuli and, depending on the severity of the lesion, results in constant pain and limited function of the affected muscles, up to and including complete paralysis and loss of strength.
What is a nerve block?
Peripheral nerves are usually multifunctional and consist of specialized motor, sensory, and autonomic nerve fibers (fascia) that are isolated from each other by sheath tissue and collectively surrounded by the epineurium as a nerve cord. The motor fasciae transmit voluntary contraction or relaxation impulses to “their” muscles, which then contract or relax. While the sensitive fasciae “transport” sensory and haptic stimuli – including pain sensations – the vegetative fibers serve to conduct impulses for control circuits that are not subject to the will. Since the peripheral nerves must in part overcome anatomical constrictions or run in special bone grooves, they can be damaged by muscle tension as a result of overload or one-sided and recurring incorrect loading due to pressure or traction. This causes corresponding motor, sensory and vegetative disturbances, which can also manifest themselves as intense pain. Total blockage of the nerve, e.g., as a result of transection, results in total paralysis of “its” muscle because the muscle no longer receives motor contraction impulses.
Causes
In addition to accidents that can lead to direct lesions of peripheral nerves, the main causes of nerve blocks are usually repetitive poor posture and strain. This is then a repetitive strain injury (SRI), which can be manifested by a variety of symptoms. The triggering factor can already be highly monotonous, prolonged writing on a computer screen, if the workplace is ergonomically suboptimally set up and at the same time there is also permanent stress via multitasking, which triggers a permanent tone in various muscles and can lead to compression damage to the peripheral nerves. Another typical cause of peripheral nerve blockage can be a herniated disc, in which the disc tissue exerts pressure on the nerve root at the exit opening from the spinal canal. Depending on the impairment of the affected nerve, pain and symptom radiation may occur to the supply areas of the affected nerve. In addition to mechanical contusions and lesions, nerve blocks can also be caused systemically by chemical agents (e.g., fungal, snake, or jellyfish poisoning), some of which can be irreversible and irreparable or even life-threatening.
Symptoms, complaints, and signs
The symptoms of a nerve block depend on its cause. If the condition is due to years of poor posture, discomfort often occurs in the back and shoulder and neck area. These may resemble tension or stiffness, or may manifest as severe pain. These symptoms can also occur in the cervical and thoracic spine if the condition was triggered by poor posture. An equally common sign is a long-lasting headache. Accidents are also one of the known causes of nerve block. If these involve a cervical vertebra syndrome due to wear and tear, discomfort occurs in the shoulder and neck area. In the worse case, paralysis or numbness can occur, which can last for a long time or even be noticed only after a certain period of time. Often a whiplash injury experienced in the past is the cause of these symptoms. If vessels or nerves are pinched, affected persons often observe tingling in the arms and hands, as if these limbs had “fallen asleep”. The underlying condition is called scaleneus syndrome and refers to the nerves that lie between the scapula, clavicle and cervical spine. Another symptom of nerve block is discomfort with breathing. These can be a result of any of the causes mentioned.
Diagnosis and course
The main symptoms of nerve block are permanent pain with concomitant tingling in the limb supplied by the affected nerve and detectable loss of strength in the limb. If a nerve block is suspected, this is followed by an examination of motor function, haptics and pain sensation. Further clinical clarification possibilities lie in the measurement of the nerve conduction velocity and in an electromyography (EMG). The EMG can provide information as to whether an identified weakness of the muscle is due to a disease of the muscle itself or to the reduced functional capacity of the nerve. In severe cases, imaging such as myelography or CT may be used. If nerve blocks are left untreated and the causes of the block do not resolve or any toxicity cannot be cleared by the body, irreversible paralysis, insensitivity to pain, and muscle atrophy will set in because the muscle is no longer being challenged.
Complications
The symptoms and complications of a nerve block depend greatly on the severity of the condition. As a rule, the affected person suffers from severe pain in the process and furthermore also from paralysis and disturbances in sensitivity. These paralyses can also spread to other regions of the body and lead to restrictions in the daily life of the affected person. Furthermore, patients also appear fatigued and powerless and are often unable to move their muscles. In some cases, patients are thus dependent on the help of other people in their daily lives and suffer from significant movement restrictions. The patient’s sensitivity to pain also increases considerably due to the nerve block, and muscle atrophy occurs if the nerve block lasts for a long period of time. The quality of life of the affected person is significantly reduced and limited by the disease. In this case, treatment can take place with the help of various therapies and thus alleviate the symptoms. However, it cannot be universally predicted whether this will be successful. Surgical interventions are also possible in some cases to release the nerve block. It is also possible that the patient’s life expectancy will be reduced because of the nerve block.
When should you see a doctor?
If tension, pain, or numbness occurs, there may be an underlying nerve block. A medical professional must be consulted if the symptoms do not subside on their own within a few days to weeks or occur quite suddenly. If severe pain or movement restrictions occur, an immediate visit to the doctor is necessary. People who have suffered a herniated disc or a serious accident with bruising and lesions are particularly susceptible to developing a nerve block. People with chronic misalignments and strains also belong to the risk groups and should consult a physician if they have the aforementioned complaints. The physician can quickly identify a nerve block and refer the patient to an appropriate specialist. The condition is treated by an orthopedist or internist, depending on the nature and severity of the complaints. The actual therapy usually also involves physiotherapists or sports physicians. To ensure a speedy recovery, close consultation with a physician must also be maintained during treatment. In severe cases, treatment at a rehabilitation center is necessary.
Treatment and therapy
For clearly diagnosed nerve blocks, the first goal of therapy is to remove the cause of the nerve damage so that the nerve can subsequently regenerate. In many cases, conservative physical therapy and other adjunctive treatments can provide relief. Special deblocking techniques can also be used, which consist of attempting passive or active remobilization of the affected muscle areas. The specially trained therapist applies specific techniques designed to release the muscle blockage. If the nerve has been severed and the distal and proximal ends are too far apart, neurosurgery at a specialized clinic may be indicated. During surgery, the two nerve endings are first identified and then connected using a special technique so that they can regenerate postoperatively.If it is not possible to connect the two nerve ends without tension, a piece of another endogenous nerve can be used as a bridging link. Alternatively, it may be possible to transfer the nerve if this avoids tension that is feared later. Such an operation must be followed by at least 2 weeks of immobilization as a regeneration phase.
Outlook and prognosis
A single nerve block subsides within a few minutes. Any signs of paralysis, numbness, or pain should resolve quickly. The outlook for rapid recovery is positive, provided the patient identifies the cause of the nerve block and consults a physician. The prognosis is less good for recurrent nerve blocks. Nerve blocks represent a great stress factor for the body. Psychological stress is also great, as the timing and intensity of the blocks cannot be predicted. In the long term, this can lead to the development of anxiety disorders and other psychological complaints. Work in physically or mentally demanding occupations is usually no longer possible, as the nerve blocks inevitably lead to absences. An alternative is drug treatment, which, however, is also associated with complications. The exact prognosis depends on whether the nerve blocks can be prevented by conservative treatment. If this is not possible, for example because of a neurodegenerative disease, the prognosis is based on the course of the causative disease. Life expectancy and quality of life also depend on the other symptoms and complaints of the causative disease.
Prevention
Prevention of nerve blocks consists mainly of avoiding recurrent incorrect stress and continuous stress without recovery periods. Regular relaxation exercises, light and regular exercise, and gymnastics, which should mainly include stretching exercises of the muscles, are recommended as active preventive measures.
Aftercare
In most cases, the affected person has very few and usually limited measures of direct aftercare available to him or her in the event of a nerve block. Therefore, the primary focus in this condition is early detection and treatment to prevent the occurrence of further complications and symptoms. Self-cure cannot occur, and the further course depends very much on the type and also on the severity of this disease. Therefore, no general prediction can be made about the further course. In many cases, patients are dependent on the measures of physiotherapy or physiotherapy for the nerve block. In this case, many of the exercises from these therapies can also be performed in the patient’s own home in order to accelerate the healing process. Many of those affected are dependent on the help and support of their own family in their daily lives. Loving conversations have a positive effect on the further course of this disease and can also prevent depression and other psychological upsets. Nerve block usually does not reduce the patient’s life expectancy.
Here’s what you can do yourself
People who suffer from chronic nerve blocks are subject to physical and emotional stress. Medical therapy can effectively treat the health problems associated with nerve block. This is best accomplished when the patient supports the treatment with some self-help measures. First, however, the cause of the nerve blockage must be determined. A complaints diary provides information about possible triggers. The patient can then take specific measures to alleviate the symptoms. Depending on the cause, these can include sports activities, massages or discussions with other sufferers. Particularly in the case of emotionally induced nerve blocks, psychotherapeutic treatment of the causes is important. After an operation, the patient initially needs a lot of rest and relaxation. Afterwards, physical exertion should be avoided for the time being, whereby the doctor’s instructions also play a role. Mild nerve blocks can often be alleviated by moderate exercise. In addition, consultation with the doctor is necessary so that the necessary measures can be taken quickly if the patient’s health deteriorates.The use of the above self-help measures should be with the consent of the physician.