myoclonus


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Related to myoclonus: myoclonus epilepsy

myoclonus

 [mi″o-klo´nus]
shocklike contractions of part of a muscle, an entire muscle, or a group of muscles; usually a manifestation of a convulsive disorder. adj., adj myoclon´ic.
A single myoclonic arm or leg jerk is normal when the person is falling asleep. Myoclonic jerks are severe with grand mal seizures. From Jarvis, 1996.
palatal myoclonus a condition characterized by a rapid rhythmic movement of one or both sides of the palate.

my·oc·lo·nus

(mī-ok'lō-nŭs, mī-ō-klo'nŭs),
One or a series of shocklike contractions of a group of muscles, of variable regularity, synchrony, and symmetry, generally due to a central nervous system lesion.
[myo- + G. klonos, tumult]

myoclonus

/my·oc·lo·nus/ (mi-ok´lo-nus) shocklike contractions of a muscle or a group of muscles.myoclon´ic
essential myoclonus  myoclonus of unknown etiology, involving one or more muscles and elicited by excitement or an attempt at voluntary movement.
intention myoclonus  that occurring when voluntary muscle movement is initiated.
nocturnal myoclonus  nonpathological myoclonic jerks occurring as a person is falling asleep or is asleep.
palatal myoclonus  rapid rhythmic, up-and-down movement of one or both sides of the palate, often with ipsilateral synchronous clonic movements of the face, tongue, pharynx, and diaphragm muscles.

myoclonus

(mī-ŏk′lə-nəs)
n.
A sudden irregular twitching of muscles or parts of muscles, occurring in various brain disorders.

my′o·clon′ic (mī′ə-klŏn′ĭk) adj.

myoclonus

[mī′ōklō′nəs]
Etymology: Gk, mys muscle; + klonos, contraction
a spasm of a muscle or a group of muscles. myoclonic, adj.

myoclonus

Lightning movement Neurology A rapid involuntary nonrhythmic spasm that can occur spontaneously at rest, in response to sensory stimulation, or with voluntary movements; myoclonias are symptoms and not, per se, diseases a sui generis Management Clonazepam, valproic acid. See Baltic myoclonus, Posthypoxic ischemic myoclonus, Sleep-related myoclonus.
Myoclonus types
Essential myoclonus Idiopathic/non-progressive, eg restless legs syndrome
Physiologic myoclonus Associated with sleep jerks and hiccups
Epileptic myoclonus Associated with epilepsy and
Symptomatic myoclonus Associated with encephalopathy, spinocerebellar degeneration, metabolic, toxic, or viral encephalopathy or trauma  

my·oc·lo·nus

(mī'ok'lŏ-nŭs)
One or a series of shocklike contractions of a group of muscles, of variable regularity, synchrony, and symmetry, generally due to a central nervous system lesion.
[myo- + G. klonos, tumult]

myoclonus

A sudden, brief, involuntary muscle contraction usually causing a jerk of a limb. This occurs most commonly as a normal phenomenon in people half asleep but myoclonic contractions are a feature of EPILEPSY and of many other brain diseases.

Myoclonus

Involuntary contractions of a muscle or group of muscles.
Mentioned in: Anoxia

myoclonus

clonic spasm or twitching of a muscle or group of muscles

my·oc·lo·nus

(mī'ok'lŏ-nŭs)
One or a series of shocklike contractions of a group of muscles, of variable regularity, synchrony, and symmetry.
[myo- + G. klonos, tumult]

myoclonus,

n a spasm of muscle or group of muscles.

myoclonus

repetitive, rhythmic contractions of a group of skeletal muscles, persisting in sleep. The result of encephalitis or myelitis caused by distemper virus in dogs. Called also canine chorea, flexor spasm and tremor syndrome.

familial reflex myoclonus
a familial disease seen in young Labrador retriever puppies; myoclonus is followed by a generalized extensor rigidity and opisthotonos.
inherited congenital myoclonus
inherited as a recessive trait in Polled Hereford cattle; at birth affected calves are unable to stand because of myoclonic jerks to skeletal muscles in response to external stimuli; affected calves are not viable. One of the diseases originally classified together as neuraxial edema.
palatal myoclonus
a condition characterized by a rapid rhythmic movement of one or both sides of the palate.
References in periodicals archive ?
Structural myoclonus including tumors that irritate the brain in a direct manner, tumors that release chemicals into the blood (as in abdominal or thoracic neuroblastoma, which causes the opsoclonus-myoclonus-ataxia syndrome), palatal myoclonus (with injury to the Guillain-Mollaret triangle in the brainstem and cerebellum);
Spinal myoclonus is an unusual, self-limiting adverse event during spinal anaesthesia (3).
The myoclonus, ocular flutter, and irritability subsided by day 16, when MRI findings returned to normal.
Neurological examination performed while the patient was under combined pharmacological antimyoclonic therapy showed an alert young man with severe myoclonus at rest.
An example of a mitochondrial disorder is myoclonus epilepsy with ragged red fibers (MERRF), in which the children have myoclonic and generalized tonic clonic seizures, dementia, ataxia, and weakness.
0 = No response to pain, or general myoclonus status.
The actual diagnoses were 26 with Parkinson's disease, 5 with essential tremor, 1 with dystonia, 3 with Parkinson's disease with dementia, 2 with multiple system atrophy, 1 with Parkinson's disease/essential tremor, 1 with corticobasal ganglionic degeneration, 1 with progressive nuclear palsy, and 1 with myoclonus.
Although WNV-associated weakness may occur without other findings suggesting acute WNV disease (14), all but 6 of our patients had meningitis or encephalitis and displayed other WNV-associated neurologic signs, including tremors, myoclonus, and parkinsonism (15-18).
Now my previously healthy 2-year-old son has been diagnosed with myoclonus (a neurological movement disorder characterized by sudden, involuntary contractions of the skeletal muscles).
Myoclonus is one of the early signs of opioid neurotoxicity.
In patients with rapidly progressive dementia, probable CJD may be diagnosed if myoclonus or typical EEG tracings are present, according to Brown et al.
These materials include comprehensive slidesets on Parkinson's disease, dystonia, tremor, Huntington's disease, myoclonus, tics and Tourette syndrome, and spasticity.