Introduction:
Mild movement during sleep is normal. It is common for individuals to shift and move to every side after going to bed. Usually, these movements slow down after settling into a comfortable position and falling asleep. However, in individuals with sleep-related movement disorders, the frequency of these movements increases as compared to the normal individual. These abnormal movements hamper the sleep quality of individuals suffering from these disorders and as a result, they can not get sufficient rest. This condition leads to daytime fatigue and a lack of concentration at school or work.
What Are Sleep-Related Movement Disorders?
International classification of sleep disorders (ICSD-3) defines sleep-related movement disorders as a subtype of sleep disorder in which repetitive movements interfere with sleep. These repetitive movements include jerky and twitching movements. However, they are completely different from movements like sleepwalking and night terrors. One such sleep-related movement disorder is benign neonatal sleep myoclonus. This disorder is seen in infants and is characterized by jerky and twitching movements only during sleep.
What Is Benign Neonatal Sleep Myoclonus?
Parents often find it fascinating to see their newborn babies sleeping. However, it can be disturbing if newborn babies show repetitive abnormal movements like twitching during sleep. This condition is called benign neonatal sleep myoclonus, a sleep-related movement disorder.
Benign neonatal sleep myoclonus appears in very young infants. The specific feature of benign neonatal sleep myoclonus is the appearance of abnormal jerky movements in infants starting from the first day of life to the age of three months. These rapid and repetitive jerks of infants' arms, legs, and torso muscles occur during sleep. These jerks are not goal-directed, unlike sleepwalking or other sleep disorders. In addition, these jerks or movements are uncontrollable and short, commonly referred to as 'myoclonus' in medical language. Another example of myoclonus is hiccups and hypnic jerks.
In benign neonatal sleep myoclonus, these jerky movements appear several times when the infant sleeps. Although it seems disturbing to the parents, this condition is usually not harmful to babies. However, without measuring brain waves, many times, it can be mistaken for epilepsy.
The important thing to notice in this sleep disorder is the disappearance of this abnormal movement after the newborn is awakened.
Since this disorder is thought to resolve without further complications within three months, treatment is typically not indicated. However, a 2010 study found that in one-third of infants, benign neonatal sleep myoclonus did not go away by the time they were three months old. Therefore, more research is needed on this disorder.
What Are the Causes of Benign Neonatal Sleep Myoclonus?
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The cause of benign newborn sleep myoclonus is unknown. Researchers believe the abnormal motions occur when the protective sheath around a baby's spinal cord is not fully grown. This circumstance may cause the body to carry out impulses that might otherwise be blocked or resisted.
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Benign newborn sleep myoclonus may tend to run in families. Myoclonic jerks in babies can be induced by repetitive noises or rocking.
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Although most cases of benign neonatal sleep myoclonus occur in newborns born to women who do not use drugs, the disorder is common among babies born to moms who are addicted to opioids. Therefore, the use of opioids can be considered a risk factor for this disorder.
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The development of this condition could be influenced by transient serotonin imbalance and hereditary factors.
What Are the Symptoms of Benign Neonatal Sleep Myoclonus?
According to the international classification of sleep disorders, revised: diagnostic and coding manual (ICSD-2, ICSD-3), the symptoms of benign neonatal sleep myoclonus are as follows:
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Repetitive myoclonic jerks involve the whole body, hands, legs, or trunk (the body part to which the head, arms, and legs attach. It consists of the buttocks, back, lower abdomen, shoulders, and chest).
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Movements arise in early infancy, generally from birth up to six months.
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Movements that arise only during sleep (when a newborn is sleeping).
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Movements that stop suddenly and consistently when the child is awakened.
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A disorder with no other explanation for the movements, such as drug usage, a neurological problem, or a sleep issue.
In addition, researchers examined brain and muscle activity in newborns with benign neonatal sleep myoclonus using electroencephalography (EEG) and electromyography (EMG). The results suggest that even though muscles show twitches resembling those seen during seizures, brain waves in benign neonatal sleep myoclonus do not resemble seizures.
What Are the Differential Diagnosis of Benign Neonatal Sleep Myoclonus?
Differential diagnosis means conditions that exhibit similar symptoms as benign neonatal sleep myoclonus. Benign neonatal sleep myoclonus can be confused with the following conditions:
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Neonatal seizures.
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Benign non-epileptic infantile spasms.
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Drug withdrawal
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Periodic limb movement disorder (PLMD).
What Is the Treatment of Benign Neonatal Sleep Myoclonus?
There is no need for treatment because benign newborn sleep myoclonus events or attacks and the disorder itself typically cure on its own. However, controlling the baby's limbs or administering anticonvulsant medications may aggravate symptoms. On the other hand, parents or caregivers may want to safeguard the area surrounding the baby, so they do not injure themselves with their abnormal, involuntary movements.
What Is the Prognosis of Benign Neonatal Sleep Myoclonus?
The prognosis of benign neonatal sleep myoclonus is excellent because this condition is considered self-limiting and usually resolves in two to seven months.
Conclusion:
Neonatal sleep myoclonus is a harmless syndrome identified by myoclonic jerks that occur only during sleep and manifest themselves soon after birth or in the first month of life. There are no connections with abnormal growth, mental abnormalities, or seizures.
The electroencephalogram (EEG) comes normal for these babies, and there is no link between it and the myoclonic jerks. Myoclonus occurs in all sleep stages. However, its frequency varies by state and is highest during peaceful sleep. As previously thought, it is not related to an arousal response.
The development of this condition may be influenced by transient serotonin imbalance and hereditary factors. In addition, involuntary movements can be triggered by the noise or rocking of the baby. This is a self-limiting condition that resolves on its own with no treatment requirement.
