The anatomical branches of the facial nerve are: posterior auricular, posterior cervical, cervical, mandibular, buccal, temporal, and zygomatic.
The facial nerve (cranial nerve VII) is a complex nerve responsible for various functions, including facial expression, taste sensation from the anterior two-thirds of the tongue, and control of some salivary glands. Understanding its anatomical branches is crucial in diagnosing and treating conditions affecting facial nerve function, such as Bell's palsy.
Key Anatomical Branches
Here's a breakdown of the major branches of the facial nerve and their primary functions:
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Posterior Auricular Nerve: This branch innervates the occipitofrontalis muscle (back part) and the posterior auricular muscle, which are involved in scalp movement and ear movement, respectively.
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Temporal Branch: This branch supplies the frontalis muscle (forehead), orbicularis oculi (muscle around the eye responsible for closing the eyelid), and corrugator supercilii (muscle that draws the eyebrows together). It is critical for forehead movements and eye closure.
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Zygomatic Branch: This branch innervates the orbicularis oculi (lower part) and muscles of the upper cheek, contributing to smiling and other facial expressions.
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Buccal Branch: The buccal branch supplies muscles of the cheek, including the buccinator and orbicularis oris. These muscles are essential for eating, whistling, and other oral movements.
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Mandibular Branch: This branch innervates the depressor anguli oris (depresses the corner of the mouth), depressor labii inferioris (depresses the lower lip), and mentalis muscle (wrinkles the chin). These muscles are vital for lower facial expressions.
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Cervical Branch: The cervical branch innervates the platysma muscle, a broad muscle in the neck that wrinkles the skin and depresses the lower jaw.
The posterior cervical branch mentioned in the provided reference is less frequently cited in standard anatomical texts, and its function may be related to variations in nerve distribution. The seven branches mentioned in the source likely correspond to an anatomical variation observed in the studied subject.
Clinical Significance
Damage to any of these branches can result in specific facial paralysis or weakness, depending on the branch affected. For example, damage to the buccal branch can cause difficulty with smiling and cheek movement, while damage to the temporal branch can lead to an inability to raise the eyebrows or close the eye fully.
