The brain controls the skeletal muscles, also known as voluntary muscles, by the use of specialised nerves. The phrase “neuromuscular system” refers to the way the nervous system and the musculature of the body work together to allow for movement.
The Neuromuscular System
A signal is sent to a group of neurons (nerve cells) in your brain known as higher motor neurons when you want to move a certain part of your body. Upper motor neurons have longer “tails,” or axons, that travel through the brain and into the spinal cord. These top motor neurons connect with lower motor neurons in the spinal cord. The axons of lower motor neurons in the spinal cord travel directly to the muscles they regulate via nerves in the arms and legs. Lower motor neurons are found in the lower region of the spinal column.
To serve a single muscle fibre in the body, lower motor neurons might number anywhere from 50 to 200 or more. Each lower motor neuron can be divided into a plethora of smaller branches. Each branch’s ultimate end is referred to as a presynaptic terminal. Another name for this link between the nerve and the muscle is the “neuromuscular junction.”
As an electrical signal travels down the nerves from the brain to the presynaptic terminals, acetylcholine is released. This chemical can be detected by specialised sensors known as receptors in muscle tissue. If a sufficient number of receptors are stimulated, acetylcholine can produce muscular contractions in your body.
Neuromuscular disorders encompass a wide range of conditions.
Identifying Neuromuscular Diseases
The symptoms of neuromuscular disease vary depending on the ailment and can range from imperceptible to life-threatening. Some of these signs and symptoms are listed below:
- Weakness in the muscles
- Heavy muscles
- Muscular cramping
- Muscle spasticity, often known as stiffness, which can subsequently lead to abnormalities in the joints or skeleton
- Muscle pain
- Difficulty in taking breaths
- Complications in swallowing
Causes of Neuromuscular Diseases
The following may cause a neuromuscular disease;
- Changes in genetic material
- Infection due to a virus
- Autoimmune disorder
- Hormonal disorder
- Metabolic disorder
- Dietary deficiency
- Certain medications and toxins
Disorders of the Neuromuscular System
The four basic categories used to classify some of the most frequent illnesses affecting the neuromuscular system are as follows:
- Motor neuron disorders cause the lower (and often upper) motor neurons to die gradually and can be inherited. Hereditary motor neuron diseases include infantile progressive spinal muscular atrophy (SMA1), intermediate spinal muscular atrophy (SMA2), juvenile spinal muscular atrophy (SMA3), and adult spinal muscular atrophy. The most common form of motor neuron disease, often known as Lou Gehrig’s disease, amyotrophic lateral sclerosis, or just motor neuron disease, is not inherited and has no known cause. ALS and Lou Gehrig’s disease are two other names for this ailment.
- Neuropathies are conditions in which the peripheral nervous system, which includes all nerves outside of the spinal cord, is damaged. Some of the diseases that might damage the peripheral nerves include Charcot-Marie-Tooth disease, diabetes (if not well controlled), and autoimmune disorders such as chronic inflammatory demyelinating neuropathy (CIDP).
- Neuromuscular junction abnormalities are neuromuscular diseases in which the signal that causes a muscle to move (contract) is unable to bridge the space between the nerve and the muscle. The most prevalent of these diseases is myasthenia gravis, an autoimmune condition in which the immune system produces antibodies that attach to the neuromuscular junction and block nerve impulse transmission to the muscle.
- Myopathies, which include muscular dystrophies, are caused by a range of genetic disorders that prevent muscle tissue from being preserved and repaired. Muscular dystrophies, generally known as “muscle wasting,” manifest themselves in a variety of ways. Some examples include Becker muscular dystrophy, congenital muscular dystrophy, Duchenne muscular dystrophy, and facioscapulohumeral muscular dystrophy. Myopathies, or muscle illnesses, can be caused by a number of reasons, including an autoimmune disorder such as polymyositis or polymyalgia rheumatica, or a hormone disorder such as hypothyroidism. Myopathies can also be an uncommon adverse effect of certain drugs, such as cholesterol-lowering statins.
Neuromuscular Problems, Diagnosis, and Treatment
Blood tests, muscle biopsies, and genetic testing a just a few of the diagnostic procedures that can be performed to detect neuromuscular illnesses. An electromyography (EMG) is used to measure electric activity in response to some nerve stimulation.
Treatment differs widely depending on the condition and its severity. Some neuromuscular disorders are far easier to treat than others.
Want to learn more?
ConsidraCare’s live-in caregivers for seniors are trained to offer professional support to seniors living with chronic conditions, like neuromuscular diseases. Please reach out to us at wecare@considracare.com or call us at 1-855-410-7971 to arrange care for a loved one.
Maryam is a leading writer at ConsidraCare, specializing in senior care. Her well-researched articles are widely recognized for guiding families through the complexities of caring for loved ones, establishing her as a trusted and authoritative voice in the field.