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Hyporeflexia

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[Hippo] Hyperreflexia vs. Hyporeflexia

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Hyperreflexia, clonus and positive Hoffman's sign

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Hyporeflexia

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Hoffman's sign and hyperreflexia

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Hyperreflexia without myelopathic symptoms

Hyporeflexia refers to below normal or absent reflexes (areflexia). It can be detected through the use of a reflex hammer. It is the opposite of hyperreflexia. Hyporeflexia is generally associated with a lower motor neuron deficit, whereas hyperreflexia is often attributed to upper motor neuron lesions. The upper motor neurons are thought to inhibit the reflex arc, which is formed by sensory neurons from intrafusal fibers of muscles, lower motor neurons and appurtenant interneurons. Therefore, damage to lower motor neurons will subsequently result in hyporeflexia and/or areflexia.