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 that are affected and list their actions. Describe the mechanism of his muscle weakness. What other symptoms could the patient exhibit as a result of facial muscle weakness?
Five muscles that are affected are the following:
- Frontalis (front belly of occipitofrontalis)
- Action — raises eyebrows and wrinkles; protracts scalp
- Orbicularis oculi
- Action — closes eyelids: palpebral part does so gently; orbital part tightly (winking)
- Orbicularis oris
- Action — tonus closes oral fissure; phasic contraction compresses and protrudes lips (kissing) or resists distension (when blowing)
- Buccinator
- Action — maintains tightness of cheeks; compresses cheeks against molar teeth
- Platysma
- Action — depresses mandible (against resistance); tenses skin of interior face and neck (conveying tension and stress)
According to Zandian et al. (2014), it is probable that the mechanism of Bell’s palsy is the inflammation of the facial nerve, which would lead to its compression along the narrow segment of the fallopian canal. This would cause the compression of the facial nerve at the geniculate ganglion (Warner et al., 2022). The aforementioned inflammation would initially result in a temporary loss of sensory or motor function. However, this can still lead to permanent nerve degeneration later on.
Aside from the facial droop and muscle weakness that the patient has exhibited, the following symptoms could also manifest (Mayo Clinic, 2022):
- Changes in amount of tears and saliva produced
- Difficulty making facial expressions, such as closing your eye or smiling
- Drooling
- Headache
- Increased sensitivity to sound on affected side
- Loss of taste
- Pain around the jaw on affected side
- Pain in or behind ear on affected side
References:
Mayo Clinic. (2022, May 4). Bell’s palsy. Retrieved September 23, 2022, from https://www.mayoclinic.org/diseases-conditions/bells-palsy/symptoms-causes/syc-20370028
Warner, M. J., Hutchison, J., & Varacallo, M. (2022). Bell palsy. In StatPearls [Internet]. StatPearls Publishing.
Zandian, A., Osiro, S., Hudson, R., Ali, I. M., Matusz, P., Tubbs, S. R., & Loukas, M. (2014). The neurologist’s dilemma: A comprehensive clinical review of Bell’s palsy, with emphasis on current management trends. Medical Science Monitor : International Medical Journal of Experimental and Clinical Research, 20, 83-90. https://doi.org/10.12659/MSM.889876