This is patient AM, 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 co-morbidities. 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?
The following muscles are affected by Bell’s palsy:
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Frontalis
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Actions: Elevates the eyebrows and wrinkles the forehead.
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Orbicularis oris
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Actions: Closes, protrudes, and compresses the lips.
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Orbicularis oculi
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Actions: Closes the eyelids.
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Buccinator
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Actions: Compresses cheek into the teeth for chewing.
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Platysma muscles
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Actions: Depresses and wrinkles skin of lower face and mouth
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The sudden muscle weakness observed from the patient is due to a condition called Bell’s palsy, wherein the nerve that controls the movement of the muscles in the face has been damaged.
The most probable mechanism of Bell's palsy is an inflammatory process of the facial nerve leading to its compression along this narrow segment of the fallopian canal. This inflammation initially causes a temporary loss of sensory or motor function, but can lead to permanent nerve degeneration later (Ali et al., 2014).
Other symptoms of this condition include the following:
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Difficulty speaking, eating or drinking
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Drooling
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Dry eyes
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Facial or ear pain
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Headache
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Loss of taste
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Ringing in ears (tinnitus)
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Sensitivity to sounds
REFERENCES:
Ali, Irfan et al. “The neurologist's dilemma: A comprehensive clinical review of Bell's palsy, with emphasis on current management trends.” NCBI, 20 January 2014, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3907546/.
“Bell's Palsy: Symptoms, Diagnosis & Treatment.” Cleveland Clinic, 29 May 2020, https://my.clevelandclinic.org/health/diseases/5457-bells-palsy.