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 five muscles that are affected by Bell’s palsy are the frontalis, orbicularis oculi, orbicularis oris, buccinator, and the platysma muscles. The frontalis includes the actions of elevating eyebrows, wrinkling skin of forehead, and retracting scalp. The orbicularis oculi, allows the closing of the eyelids. The orbicularis oris allows the lips to move, either close, to pucker or purse. The buccinator allows us to compress the cheeks for various purposes. The platysma muscles allow us to do facial expressions through the attachments in the different parts of the face and lip, by either tensing or depressing. The one mechanism of Bell’s palsy is unknown, but the most common belief is that it is the inflammation of the nerve that is responsible for controlling the muscles on the side of the face (cranial nerve VII), which is caused by viral means. Other than the apparent visual symptoms, other symptoms may also include drooling, headaches, loss of taste, as well as pain experienced around the affected side.