The term neuromuscular disorder is used to describe a wide range of conditions related to nerve cells in the spinal cord, called motor neurons; nerves; the connection between nerve and muscle, called the neuromuscular junction; and muscles themselves. Muscle cells and nerve cells need each other for proper function and health. If a nerve is malfunctioning for a long time, the muscle will also malfunction and eventually wither away, also known as atrophy.
There are dozens of neuromuscular conditions that may cause spasticity (unusual stiffness of the muscles), tingling, numbness, cramps, fatigue, pain, or partial-to-complete paralysis, depending on the disorder.
Neuromuscular disorders can be grouped very broadly into disorders of the motor neurons; disorders of the nerves that connect to muscles; disorders in signaling from the nerve to the muscle; called neurotransmission; and disorders of the muscles. Within each category, there are several separate disorders. Some examples of each are listed here.
Motor neuron disorders
The types of symptoms and how they start depends on the type of neuromuscular disorder and the areas of the body that are affected. Depending on the disorder, symptoms can first appear at any time in a person’s lifetime, including infancy, childhood, and adulthood.
Some symptoms common to neuromuscular disorders include:
Because of the broad range and number of neuromuscular disorders, there are also a large number of proven and suspected causes. These include infections, autoimmune diseases, genetic diseases, toxic exposure, and more.
The first step a doctor will take is to ask many questions about all of the symptoms listed above to find out what symptoms are present for each individual, including things he or she may not have perceived as a problem. Once the symptoms have been identified, the physician will likely ask:
The physician will also perform a physical examination and a neurologic examination. She or he will look at your muscles and test them for strength, flexibility, and stamina. The doctor will observe eye muscles during eye movements, watch tongue and mouth movements, check sensations on the face and elsewhere, test reflexes, and watch a person walk and move their limbs as much as possible.
Many diagnostic tests can be helpful to determine, which—if any—neuromuscular disorder is present, including:
Most neuromuscular disorders are treated with a team approach that includes taking medicine and doing physical and occupational therapy. Some neuromuscular disorders, such as carpal tunnel syndrome, can be treated with surgery. Others, such as myasthenia gravis, are treated with steroids to reduce inflammation and plasma exchange to remove the antibodies causing the problem. New treatments have been developed for a couple of genetic neuromuscular diseases including some forms of muscular dystrophy and spinal muscle atrophy, and many more are being developed.
Living well with a neuromuscular disorder depends very much on the disorder. One of the most important things is to work with the health care team to find a treatment plan that is realistic for each individual, and then stick to that plan. It is helpful to keep regular appointments so that the plan can be adjusted as symptoms change.
Exercise may or may not be helpful depending on the condition. It is important to talk with the health care team about any exercise plans. Physical therapists can help an individual modify exercises so that they can be done safely in ways that support muscle and nerve health.
There is no diet that is proven to improve neuromuscular disorders. Following a diet that is heart-healthy and maintaining a healthy weight both promote the ability to keep moving, which muscles need to stay healthy. Following a diet that prevents or controls diabetes is important for maintaining the health of nerves that connect to muscles.
Healthy sleep is essential for health and recovery. If a person can’t sleep about 7 hours per night, on most or all nights, it is a good idea to talk to the health care team about sleep.
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