Myoclonus refers to quick, and sudden muscle spasms that are involuntary in nature and can’t be stopped or controlled. It may chiefly involve one muscle or a group of muscles and the movements may be sudden jerking, quivering, or twitching occurring in a pattern or just randomly. One common form of myoclonus is sudden jerky movement during ‘Hiccups’ or ‘Sleep starts’ that one may feel just before falling asleep. These forms of myoclonus are natural and usually occur in healthy people and doesn’t show any sign of a problem. But there are other forms that may occur due to an underlying disorder of the nervous system causing conditions like epilepsy, multiple sclerosis, dementia, Parkinson's disease, or sometimes may even occur owing to a reaction to a medication.

Also Read: Incessant Hiccups Could Indicate Serious Health Problems That Need Urgent Attention
Myoclonus

In general, myoclonus can be treated by remedying the underlying condition, but in cases where the myoclonus is idiopathic in nature, i.e., the actual cause remains unknown or can't be specifically treated, then the treatment mainly focuses on reducing the effects of myoclonus on the quality of life.

Causes

Myoclonus may be caused by a variety of underlying problems. It usually happens when the nervous system works in an unusual way triggering the nerve cells to misfire and send the wrong signal to the muscles. Although, doctors may think that several parts of the brain may get involved during this action quite often the exact cause is not known.

Types

Depending upon the underlying condition or the movement or the causative factor behind it, myoclonus can be categorized into the following types:

Action: Triggered by a sudden movement, this type of myoclonus can chiefly affect your arms, legs, face, and voice.

Physiological: This type of myoclonus usually happens in people with no underlying health problems and rarely requires treatment. It includes sudden twitches during hiccups, shaking or spasming when you’re startled or anxious, spasms when you’re just falling asleep or waking up and infant muscle twitching during sleep or after a feeding.

Essential: This is often hereditary and characterized by twitches or jerks. It is usually idiopathic in nature and may often become more severe over time.

Sleep: This type of myoclonus relates to sudden muscle spasm while asleep and mainly affects the lips, eyes, fingers, and toes.

Epileptic: This form is usually noticed in people diagnosed with seizure disorders (epilepsy).

Progressive Myoclonus Epilepsy (PME): A kind of epileptic myoclonus, which is usually noticed to start in children and teens and often tends to get worse over time.

Symptomatic (Secondary): The symptomatic form is caused by another underlying health condition, such as an infection, a stroke, a brain tumor, lack of oxygen, kidney or liver failure, metabolic disorders, lipid storage disease, chemical or drug poisoning or even coronavirus.

Stimulus-Sensitive: A type of sudden jerky movement that is mainly triggered by things in the world around us like lights, noise, or movement.

Brainstem: Hearing a sudden noise or suddenly noticing something, one might have a grimace and this, in turn, can cause your elbows, knees, neck, and other parts of your body to flex.

Palatal: This form causes a tremor in the roof or soft palate of your mouth and may primarily involve the face, tongue, diaphragm, and throat. These muscle twitches are often very fast and random and a person could have as many as 150 in a minute. The Palatal form of movement might happen while a person is sleeping.

Cortical Reflex: Cortical reflex form is often considered as a kind of epilepsy and people who have it are prone to sudden jerk-like movements in their upper limbs and face.

Reticular Reflex: This kind of myoclonus can cause twitching or jerking throughout the body and usually get triggered by movements or something you see or hear.

Risk Factors

Myoclonus is usually diagnosed at equal rates in both males and females. But the risk of myoclonus increases if you have a family history of this condition.

Symptoms

People with myoclonus often describe their signs and symptoms as sudden involuntary jerks, shakes or spasms. The symptoms may vary from mild to severe and generally depends upon the underlying health condition. These movements are usually described as:

  • Sudden
  • Uncontrolled and unpredictable
  • Brief in duration
  • Involuntary
  • Shock-like
  • Varied intensity and frequency
  • Localized to one part of the body or spread all over the body
  • Sometimes severe enough to interfere with normal eating, speaking or walking

Diagnosis And Treatment

If you suddenly notice any of the above-mentioned signs and symptoms, do not delay further and consult a doctor immediately. The doctor usually does a thorough physical check-up, acknowledges the patients past medical history and conducts the following diagnostics:

Electroencephalogram (EEG): This process tracks and records the patterns of electrical activity that happens in the brain to figure out where the myoclonus starts.

Electromyography (EMG): This test checks the health of your muscles and the nerve cells that control them.

Magnetic Resonance Imaging (MRI): This procedure chiefly records the detailed pictures of the brain, spinal cord, and other body parts that might be involved.

Evoked Potential Studies: This diagnostic process measures the electrical activity of the brain, brainstem and spinal cord that is triggered by touch, sound, sight and other stimuli.

Blood Tests: This test looks for conditions like metabolic disorders, autoimmune conditions, diabetes and kidney and liver disease.

Also Read: Diabetes Mellitus: Know Your Fasting, Post-Prandial, HBA1C Numbers

Treatment

The doctor usually focuses on treating the condition by effectively remedying the underlying cause. And cases, where the underlying cause cannot be treated or cured, doctors usually try to subside the underlying symptoms to ease living. This includes:

  • Medications like tranquilizers and anti-convulsant
  • Therapies
  • Surgery
  • Clinical Trial