In unilateral hypoglossal nerve palsy, the tongue muscle on the diseased side is paralyzed, and the tongue tip is atrophied on the diseased side when extending the tongue; in bilateral hypoglossal nerve palsy, the tongue muscle is completely paralyzed, and the tongue cannot be extended at the floor of the mouth, and there is difficulty in speech and swallowing. Injury to the hypoglossal nerve (medullary palsy) accompanied by injury to the posterior group of cerebral nerves (the posterior group of cerebral nerves (linguopharyngeal nerve, vagus nerve, paraglossal nerve, hypoglossal nerve) all originate from the medulla oblongata and are closely related to each other, collectively called medullary nerves). When the central hypoglossal nerve injury (nuclear and supranuclear) and the peripheral hypoglossal nerve of the skull base segment are combined with the posterior group of cerebral nerve injury, they are often compounded in the clinical manifestations of the lesions related to the medulla oblongata and appear as medulla oblongata paralysis, which is one of the most common and major types of hypoglossal nerve injury. The nucleus of the hypoglossal nerve is very close to the nucleus of the hypoglossal nerve, so the nuclear lesion of the hypoglossal nerve is often a bilateral damage to the nucleus of the hypoglossal nerve, which can produce ipsilateral orbicularis oris muscle paralysis in addition to lingual muscle paralysis.