Myoclonus is a brief, involuntary, irregular (lacking rhythm) twitching  of a muscle or a group of muscles, different from clonus, which is rhythmic or regular. Myoclonus describes a medical sign and, generally, is not a diagnosis of a disease. These myoclonic twitches, jerks, or seizures are usually caused by sudden muscle contractions (positive myoclonus) or brief lapses of contraction (negative myoclonus). The most common circumstance under which they occur is while falling asleep (hypnic jerk). Myoclonic jerks occur in healthy people and are experienced occasionally by everyone. However, when they appear with more persistence and become more widespread they can be a sign of various neurological disorders. Hiccups are a kind of myoclonic jerk specifically affecting the diaphragm. When a spasm is caused by another person it is known as a provoked spasm. Shuddering attacks in babies fall in this category. Myoclonic jerks may occur alone or in sequence, in a pattern or without pattern. They may occur infrequently or many times each minute. Most often, myoclonus is one of several signs in a wide variety of nervous system disorders such as multiple sclerosis, Parkinsons disease, dystonia, cerebral palsy, Alzheimers disease, Gauchers disease, subacute sclerosing panencephalitis, Creutzfeldt–Jakob disease (CJD), serotonin toxicity, some cases of Huntingtons disease, some forms of epilepsy, and occasionally in intracranial hypotension.
Bites to the face of humans constitute only 10 percent of the total. Two-thirds of bite injuries in humans are suffered by children aged ten and younger.Up to three-fourths of dog bites happen to those younger than 20 years-old. In the United States, the costs associated with dog bites are estimated to be more than $1 billion annually. The age groups that suffer most from dog bites are children 5 to 9 years-old. Often, bites go unreported and no medical treatment given - these bites go unreported. As many as one percent of pediatric emergency room visits are for treatment for animal bites. This is more frequent during the summer months. Up to five percent of children receiving emergency care for dog bites are then admitted to the hospital. Bites typically occur in the late afternoon and early evening. Girls are bitten more frequently by cats than they are by dogs. Boys are bitten by dogs two times more often than girls are bitten by dogs. History
The bites of humans are recorded during the biblical era. Reports of secondary infection occurring after a human bite in children have been noted in the United States since at least 1910. Morbidity and mortality rates improved with the use of antibiotics. See also
Bite force quotient
Wilderness first aid
Dog bite
Dog bite prevention

References


== External links ==