Achilles tendon reflex


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Related to Achilles tendon reflex: biceps reflex

A·chil·les re·flex

, Achilles tendon reflex (ă-kil'ēz),
a contraction of the calf muscles when the tendo calcaneus is sharply struck.

Achilles tendon reflex

a deep tendon reflex consisting of plantar flexion of the foot when a sharp tap is given directly to the tendon of the gastrocnemius muscle at the back of the ankle. This reflex is often absent in people with peripheral neuropathies or diabetes. A sluggish return of the flexed foot may occur in patients with hypothyroidism and lower motor neuron diseases. A hyperactive reflex may be caused by hyperthyroidism or by pyramidal tract disease, as well as by any upper motor neuron disease. Also called Achilles jerk, ankle reflex. See also deep tendon reflex.
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Elicitation of the Achilles tendon reflex

ankle reflex

An abrupt plantar jerk of the ankle, evoked by tapping the Achilles tendon with an unrestricted forefoot.

Method
Slightly externally rotate at the hip and gently dorsiflex the foot, tapping the Achilles tendon with a reflex hammer; there should be a reflex contraction of the gastrocnemius muscle (plantar flexion).

A·chil·les re·flex

, Achilles tendon reflex (ă-kil'ēz rē'fleks, ten'dŏn rē'fleks)
A contraction of the calf muscles when the tendo calcaneus is sharply struck.
Synonym(s): ankle reflex, triceps surae reflex.
References in periodicals archive ?
In my experience, a delayed Achilles tendon reflex (ATR) return is the most reliable physical sign of hypothyroidism, and other investigators have made the same observation.