Affected Muscles:
- Occipitofrontalis
Action: Draws scalp anteriorly, raise eyebrow, and wrinkles skin in the forehead horizontally as in look of surprise.
- Orbicularis oris
Action: Closes and protrudes lips, as in kissing; compresses lips against teeth; and shapes lips during speech.
- Orbicularis oculi
Action: Closes eye, blinks, & squint.
- Buccinator
Action: Presses cheeks against teeth and lips, as in whistling, blowing, and sucking; draws corner of mouth laterally; and assists in mastication (chewing) by keeping food between the teeth (and not between teeth and cheeks).
- Platysma
Action: Draws outer part of lower lip inferiorly and posteriorly as in pouting; depresses mandible.
Mechanism:
- The muscle weakness in Bell’s Palsy results from the inflammation of the seventh cranial nerve, which connects the brain to the affected muscles controlling expression as well as taste, tears, saliva, and ear sensations (Bell’s Palsy, 2022).
Other symptoms:
- drooling
- difficulty to close eyes
- loss of taste
- facial pain
- excessive tearing on one eye
- pain around the jaw
References:
Mayo Foundation for Medical Education and Research. (2022) Bell’s Palsy. Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/bells-palsy/symptoms-causes/syc-20370028#:~:text=In%20Bell’s%20palsy%2C%20that%20nerve,the%20middle%20of%20the%20ear.
Tortora, G. J., & Derrickson, B. (2016). Chapter 11: The Muscular System. In Principles of Anatomy and Physiology (15th edition). Wiley. Retrieved from https://www.google.com.ph/url?sa=i&rct=j&q=&esrc=s&source=web&cd=&ved=0CAIQw7AJahcKEwi4m_OvkpuBAxUAAAAAHQAAAAAQAg&url=https%3A%2F%2Fhandoutset.com%2Fwp-content%2Fuploads%2F2022%2F05%2FPrinciples-of-anatomy-and-physiology-Wiley-2017-Derrickson-Bryan-H._-Tortora-Gerard-J..pdf&psig=AOvVaw3MGogf51os64NiWCtHEzVc&ust=1694266926809150&opi=89978449.