Monoplegia is a type of paralysis that impacts one limb, most often an arm, but it can also affect one of your legs. Sometimes it can be a temporary condition, but in other cases it can be permanent.

Your body has an extensive system of nerves. One of the functions of your nervous system is to move your body’s muscles. This includes movements that you control (voluntary) and those that you don’t (involuntary).

When a part of the nervous system becomes damaged, it can disrupt the signaling activity to a muscle or muscle group. This can lead to muscle weakness (paresis) or paralysis in the affected area.

Damage to the nervous system can include the brain, spinal cord, or one or more nerves, and affect a limb on either the upper or lower part of the body.

The symptoms of monoplegia can come on suddenly, as in the case of an injury or stroke. The symptoms may also progress gradually over time due to the progression of cerebral palsy or a motor neuron disease.

The main symptom of monoplegia is the inability to move one of your arms or legs.

You may also experience the following symptoms in or around the affected limb:

Monoplegia is often caused by cerebral palsy. It can also be caused by an injury or trauma to the brain, spinal cord, or affected limb.

Other possible, though less common causes, include:

Both monoplegia and hemiplegia are types of paralysis. But how do they differ from each other?

Monoplegia is paralysis that affects a single limb on the upper or lower part of the body. So, for instance if you had monoplegia and couldn’t move your right arm, you would still be able to move your right leg.

Hemiplegia is paralysis that affects one side of the body. Either the right side or the left side of the body can be affected.

If you had hemiplegia on your right side, you wouldn’t be able to move your right arm and right leg. The muscles on the right side of your face might also be affected.

While the two conditions are different, monoplegia and hemiplegia share many of the same potential causes. This can include things like injury, cerebral palsy, and stroke.

There’s currently no cure for paralysis, including monoplegia. Instead, treatment aims to address the symptoms while improving quality of life.

Treating the underlying cause of monoplegia is important.

Some of the potential treatment options for monoplegia include:

  • Physical therapy: PT can be used to help maintain or build strength, flexibility, and mobility in the affected limb. Stretches, exercises, or massage may be used to help stimulate muscles and nerves.
  • Occupational therapy: Occupational therapy teaches different techniques to make it easier to perform everyday tasks like getting dressed, bathing, or cooking.
  • Assistive devices: These devices can make day-to-day activities easier. A few examples include walkers, wheelchairs, specialized grips and handles, and voice-activated devices.
  • Medications: Medications may help reduce some of the symptoms associated with monoplegia. Examples include pain medications to alleviate discomfort and muscle relaxants for muscle stiffness or spasms.
  • Surgery: If monoplegia is due to a tumor or nerve compression, surgery may be needed.

Monoplegia is a type of paralysis that impacts one limb, such as an arm or leg on one side of your body. This happens when damage to a part of the nervous system disrupts nerve signaling to the muscles in the affected limb.

Monoplegia can affect the upper or lower body, either one arm or one leg. Symptoms can appear suddenly or progress gradually over time.

Monoplegia is often caused by cerebral palsy. But it can also be the result of an injury or trauma to the brain, spinal cord, or the affected limb.

Although monoplegia can sometimes improve over time, it may be permanent in some individuals. Treatment options typically focus on alleviating symptoms and improving quality of life.