Nerves and muscles, working together as the neuromuscular system, make your body move as you want it to. They also make sure you do things you don’t even think about, such as breathe.

How does the neuromuscular system work?

Nerves have cells called neurons. Neurons carry messages from the brain via the spinal cord. The neurons that carry these messages to the muscles are called motor neurons.

Each motor neuron ending sits very close to a muscle fibre. Where they sit together is called a neuromuscular junction. The motor neurons can release a chemical, which is picked up by the muscle fibre. This tells the muscle fibre to contract, which makes the muscles move.

Diseases involving the neuromuscular system

Many different diseases affect the neuromuscular system, and together they are known as neuromuscular diseases.

Some examples of neuromuscular diseases are:

• neuropathies (problems with the nerves), such as Charcot-Marie-Tooth disease or motor neuron disease
• myopathies (problems with the muscles), such as muscular dystrophy
• neuromuscular autoimmune conditions, such as myasthenia gravis or multiple sclerosis.

In some neuromuscular diseases, the nerves are damaged, and don’t carry messages from the brain as they should. In others, the muscles are damaged, and they either can’t receive messages from motor neurons, or they can’t respond as they should.

Either way, the person affected can have problems with tiredness, weakness, muscle pain, wasting and spasms. Often, the symptoms affect the arms and legs more than other parts of the body.

In severe cases, neuromuscular diseases can lead to difficulties in swallowing, speaking and even breathing.

Treatments for neuromuscular disorders generally aim to ease symptoms and improve quality of life, but in many cases there are no effective medications. Unfortunately, most neuromuscular disorders cannot currently be cured.