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.
- Frontal Belly - draws scalp anteriorly, wrinkles skin of forehead and raises eyebrows.
- Orbicularis Oris - muscle responsible for kissing as it closes and protrudes lips.
- Buccinator - presses cheeks against teeth and lips as in whistling, blowing and sucking. Assists in chewing and keeping food between teeth
- Orbicularis Oculi - draws eyebrow inferiorly and wrinkles skin of forehead vertically as in frowning
- Platysma - draws outer part of lower lip inferiorly and posteriorly as in pouting and it depresses mandible
Describe the mechanism of his muscle weakness.
- Bell's palsy, also known as facial paralysis, is the paralysis of the muscles of facial expression due to damage or disease of the facial (VII) nerve. The paralysis causes the entire side of the face to droop which causes difficulty in swallowing, closing one's eye or difficulty in puckering the lip. Possible causes include inflammation of the facial nerve due to an ear infection or damage to the facial nerve due to ear surgery. Patients can recover from Bell's palsy but it can be permanent for others.
What other symptoms could the patient exhibit as a result of facial muscle weakness?
- Drooling and difficulty in swallowing
- Not being able to wrinkle one's forehead
- Inability to pucker one's lips and close one's eye
- Facial pain
- Inability to express anything through the face
- Pain around the jaw or ear
References:
Bell’s Palsy. (2023). National Institute of Neurological Disorders and Stroke. https://www.ninds.nih.gov/health-information/disorders/bells-palsy
Tortora, G. J., & Derrickson, B. (2017). Principles of anatomy & physiology. Fifteenth edition; Wiley Loose-Leaf Print Companion. Hoboken, New Jersey, John Wiley & Sons, Inc.