What are other Names for this Condition? (Also Known As/Synonyms)

• Muscle Twitch
• Myoclonus

What is General Myoclonus? (Definition/Background Information)

• General Myoclonus, or simply Myoclonus, refers to the random involuntary jerking of a muscle or group of muscles. This can occur in any muscle in the body and may be due to a muscle contraction or relaxation. It does not appear at any specific age and can be seen in both children and adults
• Myoclonus is caused by a sudden and involuntary electric pulse/signal coming from the brain to the body. The risk factors for Myoclonus are not well understood, but all have to do with nerve damage or disruption of signaling between the nervous system and muscles
• There are several forms of Myoclonus, and some only affect certain areas of the body. These may be classified in various ways and can include:
  • Essential Myoclonus
  • Physiologic Myoclonus
  • Progressive Myoclonus Epilepsy (PME)
  • Sleep Myoclonus
  • Symptomatic (Secondary) Myoclonus
• The characteristic signs and symptoms of General Myoclonus are sudden jerks, spasms, or erratic movements. A diagnosis of Myoclonus can include a variety of tests to measure brain activity and other bodily functions
• The complications associated with Myoclonus are typically due to the disorder or disruption that cause the spasms and generally not as a result of the muscle twitches. Hence, the treatment for General Myoclonus focuses on improving the signs and symptoms and addressing the underlying cause. This may involve the use of medications and surgical procedures, if necessary
• The prognosis for an individual with General Myoclonus is typically good, unless the condition is caused by a more severe disease (underlying condition). Since Myoclonus may develop from multiple causes and sometimes sporadically, it may be difficult to prevent the same

Who gets General Myoclonus? (Age and Sex Distribution)

• In general, Myoclonus can occur in any individual   of any age group. Individuals belonging to certain age groups may be more susceptible to some forms of Myoclonus
• However, it is not considered a health issue if Myoclonus is infrequent, for example when it manifest as a hiccups or a random eye twitch
• The condition occurs in males and females equally and does not affect any specific racial or ethnic group, meaning all are at equal risk

What are the Risk Factors for General Myoclonus? (Predisposing Factors)

The risk factors for Myoclonus involve issues with damaged nerves or irregular signaling pathways between the brain and body. Having any one or more of the following can lead to some forms of Myoclonus:

• Head or spinal neck injury such as from vehicle accidents or participation in sports
• Brain tumors
• Kidney or liver failure
• Excessive drug or chemical exposure

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others. 

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of General Myoclonus? (Etiology)

General Myoclonus is caused by a random signal in the form of an electrical impulse coming from the brain to the body. This leads to the involuntary muscle spasm or jerking motion that characterizes this condition. It may develop from a variety of factors.

What are the Signs and Symptoms of General Myoclonus?

In general, the signs and symptoms of Myoclonus may include:

• Random jerking or spasm-like movements
• Sudden loss of strength due to muscles relaxing

These events have to occur regularly and be involuntary in order to be classified as Myoclonus. The signs and symptoms of any underlying causative condition may be additionally noted. Also, these may depend on the specific type of Myoclonus diagnosed in the individual.

How is General Myoclonus Diagnosed?

• In order to diagnose Myoclonus a healthcare professional may perform a physical examination and check the individual’s medical history
• After the initial exams, a series of scans and tests to measure brain activity may be undertaken. These include:
  • Electroencephalography (EEG), in order to measure brain activity through the scalp
  • Magnetic resonance imaging (MRI) scan of the brain to look for tumors or areas of damage inside the brain
• Tests, such as electromyography, to check the activity levels of the individual muscles may be performed
• If these tests are inconclusive, the healthcare provider may recommend more specific tests to check the condition of other body organs such as the kidneys, liver, and immune system

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications with General Myoclonus?

The complications with General Myoclonus are mainly due to the underlying factors that result in the condition. The complications may include:

• A head injury may lead to memory loss or other developmental issues if the injury is severe enough
• Spinal cord injuries have the possibility of causing paralysis
• Kidney failure, which can lead to the requirement of a transplant, and accompanying poor quality of life
• Liver failure, which may require surgery to remove a part of the liver
• Brain tumors may cause several neurological complications that can be life-threatening

How is General Myoclonus Treated?

• The treatment for Myoclonus is focused on managing the underlying cause and treating the signs and symptoms
• Anticonvulsants, sedatives, and tranquilizers may be used to decrease severity of the myoclonic jerks

Targeting the underlying cause of Myoclonus (if the cause is treatable) may involve the use of medications, surgery, and rehabilitation, as needed.

How is General Myoclonus Prevented?

• There is no clear prevention strategy for Myoclonus since the condition can be caused by a variety of issues
• Avoiding head injuries (through use of protective head gear or helmets) caused by accidents or sports
• Avoid exposure to toxic chemicals
• Check with a healthcare professional if there is any family history of kidney or liver condition (failure), or other neurological disorders

What is the Prognosis for General Myoclonus? (Outcomes/Resolutions)

• The prognosis for General Myoclonus is typically good, since the condition by itself is not life-threatening
• However, the overall outcomes are mainly dependent on the underlying cause of neurological dysfunction and its severity

Additional and Relevant Useful Information for General Myoclonus:

Some of the types of Myoclonus that affect individuals in specific manners include:

• Action Myoclonus - jerks and spasms only occur when trying to make voluntary actions or the thought of trying to move
• Essential Myoclonus - when the myoclonic jerks are the only issue an individual has, and the condition does not worsen over time
• Sleep Myoclonus - the myoclonic jerks only happen just before an individual falls asleep