clonus


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Related to clonus: ankle clonus

clonus

 [klo´nus]
1. alternate involuntary muscular contraction and relaxation in rapid succession.
2. a continuous rhythmic reflex tremor initiated by the spinal cord below an area of spinal cord injury, set in motion by reflex testing.
ankle clonus (foot clonus) a series of abnormal reflex movements of the foot, induced by sudden dorsiflexion, causing alternate contraction and relaxation of the triceps surae muscle.
toe clonus abnormal rhythmic contraction of the great toe, induced by sudden passive extension of its first phalanx.
wrist clonus spasmodic contraction of the hand muscles, induced by forcibly extending the hand at the wrist.

clo·nus

(klō'nŭs),
A form of movement marked by contractions and relaxations of a muscle, occurring in rapid succession seen with, among other conditions, spasticity and some seizure disorders.
See also: contraction.
[G. klonos, a tumult]

clonus

(klō′nəs)
n. pl. clo·nuses
An abnormality in neuromuscular activity characterized by rapidly alternating muscular contraction and relaxation.

clon′ic (klŏn′ĭk, klō′nĭk) adj.
clo·nic′i·ty (klō-nĭs′ĭ-tē, klŏ-), clo′nism (klō′nĭz′əm, klŏn′ĭz′əm) n.

clonus

Neurology
1. A volley of muscle contractions and relaxations, occurring in rapid succession.
2. An abrupt transient muscle contraction.

clo·nus

(klō'nŭs)
A form of movement marked by contractions and relaxations of a muscle, occurring in rapid succession; seen with, among other conditions, spasticity, and some seizure disorders.
See also: contraction
Synonym(s): clonospasm.
[G. klonos, a tumult]

clonus

Repetitive contraction and relaxation of stretched muscles which have been deprived of the smoothing and controlling influence of higher centres in the nervous system, in conditions such as STROKE. A feature of an ‘upper motor neurone lesion’. Clonus is also a feature of GRAND MAL epilepsy.

clo·nus

(klō'nŭs)
A form of movement marked by contractions and relaxations of a muscle, occurring in rapid succession seen with, among other conditions, spasticity and some seizure disorders.
[G. klonos, a tumult]
References in periodicals archive ?
* Recognize the clinical manifestations of serotonin syndrome, which may include agitation, diaphoresis, hyperthermia, hyperreflexia, and clonus.
[1] In a long-term follow-up study of phenol block of the tibial nerve by Petrillo et al, 92 tibial nerve blocks with phenol were performed in 59 patients for treatment of severe spasticity of foot and it was observed that the Achilles tendon reflexes was abolished, ankle clonus eliminated and resistance to passive stretch was reduced following the procedure in all patients.
Within two weeks after starting sertraline, the woman showed numerous signs of serotonin toxicity: hypertension, tachycardia, anxiety, profuse sweating, bilateral ocular clonus, ankle clonus in the lower extremities, rhythmic jaw motions, and stuttering.
Manca et al (9) compared botulinum toxins and phenol nerve blocks to reduce ankle clonus in spastic paresis and concluded that both patient groups showed significant clonus reduction over time with the phenol group effect greater than the botulinum toxins group.
To date, no clinical study of tramadol-induced clonus is available, although there have been similar studies within the field.
Neurologic examination was limited but the patient had normal extremity tone, hyporeflexia was noted in biceps, triceps, knees, and ankles bilaterally, clonus was absent, and normal bilateral Babinski reflexes were noted.
There was hypertonia of both lower limbs and sustained bilateral ankle clonus was elicited.
According to the severity of mice with epileptic seizures, the manifestations were classified into 5 levels: (1) twitching of facial muscle; (2) nodding of head; (3) unilateral forelimb with lifting or clonus; (4) bilateral forelimb with clonus as standing; (5) falling as standing or twisting.
The kindling progression was scored according to the Racine scale: stage 1: facial clonus, wet dog shakes, and mouth; stage 2: facial movement and head nodding; stage 3: forelimb clonus; stage 4: rearing and tonic extension of forelimbs; stage 5: falling and loss of balance [13].
Mice were scored as follows: (0): if there is no seizure response, (1): if there exist immobility, closure of the eye, twitching of the ear, and appearance of facial clonus, (2): if there is nodding of head together with highly severe facial clonus, (3): if there is clonus of one forelimb, (3, 5): if there is bilateral forelimb clonus and no rearing, (4): if there is bilateral forelimb clonus accompanied with rearing, (4, 5): if there is no rearing and animals fall on a side, and righting reflex was lost in addition to generalized tonic-clonic seizures, and (5): if rearing occurred and animals fell on back together with generalized tonic-clonic seizures.
Physical examination revealed negativism, intermittent rigidity, and generalised hyperreflexia, but no clonus, autonomic dysfunction, diaphoresis, or fevers.
During the first several days of inpatient admission, she experienced progressive bilateral extremity clonus, hyperreflexia, and urinary retention.