ankle clonus


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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.

an·kle clo·nus

a rhythmic contraction of the calf muscles following a sudden passive dorsiflexion of the foot, the leg being semiflexed.

ankle clonus

A rhythmical, sustained series of flexion movements at the ankle. This is produced in people with damage to the nerve pathways in the spinal cord or brain (an upper motor neurone lesion), by a deliberate rapid, stretching of the ACHILLES TENDON, by forcibly flexing the foot. The spinal reflex arc is intact but the normal control on it, from above, is defective.
References in periodicals archive ?
Group C: these were patients with acute tramadol poisoning and ankle clonus without a specific underlying disease, who received 2 g magnesium sulfate every 8 h for the prevention of seizures.
13 Knee and ankle clonus 1986 [12] Major and 13f Transient loss of Huizenga sensation below the 1988 [13] waist and inability to move LL after fall on rib hub 5f No 11m No Deguchi 12f Weakness of the LL, et al.
They reported the most sensitive test was an exaggerated patellar tendon reflex (94%), followed by the Hoffmann sign (81%), Babinski sign (53%), and ankle clonus (35%).
Caldwell, "Botulinum toxin in gait dysfunction due to ankle clonus: a case series," NeuroRehabilitation, vol.
On examination, he had brisk tendon reflexes with ankle clonus, spastic quadriparesis, and decreased proprioceptive sensation in the lower limbs with preserved vibration sense.
* Test for ankle clonus. Push up on the ball of the foot and forcibly dorsiflex the ankle.
Physical examination revealed left ankle clonus, positive Babinski sign on the left, and left lower extremity weakness.
Motor examination of the lower limbs showed hypertonia hyperreflexia ankle clonus and bilaterally up going planters.