This is patient AM, a 28-year-old male who came in the ER because of drooping of his left face. He said he woke up and he could not move his left face.
He has no other muscle weakness. He is conscious and coherent although he had a little difficulty speaking because the left side of his lips drooped. He had normal blood pressure and he had no other comorbidities. He was diagnosed to have Bell’s palsy. Name 5 muscles which are affected and list its actions. Describe the mechanism of his muscle weakness. What other symptoms could the patient exhibit as a result of facial muscle weakness?
Muscles Affected by Bell’s Palsy
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Frontalis: raise eyebrows, facial weakness in general, & wrinkle forehead
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Orbicularis oculi: closes the eyelids and assists in pumping the tears from the eye into the nasolacrimal duct system
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Orbicularis oris: closes, protrudes and compresses the lips
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Buccinator: pressing cheeks against teeth & lips and drawing corner of mouth laterally
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Platysma muscles: depresses the mandible and lower lip and tenses the skin of the anterior neck
Mechanism of Muscle Weakness
A disease of the nerve that regulates facial muscle action is known as bell palsy. The facial nerve, often known as the seventh cranial nerve, is this nerve. These muscles become weakened or paralyzed when this nerve is damaged. You are completely unable to utilize your muscles if you are paralyzed. It controls the facial muscles on one side, including those responsible for blinking, shutting, and making facial expressions like a smile.
Other Symptoms
Other signs could be drooping of the mouth, drooling, difficulty closing one eye (resulting in dryness) or excessive tears in one eye. Additionally, people may have facial pain or other unusual sensations, taste changes or loss, and a sensitivity to loud noises.