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?
Affected muscles and their actions
Buccinator (Cheek muscles) – Maintains the tightness of cheeks | Compresses the cheeks against the teeth to aid chewing
Frontalis (Muscles on the scalp) – Raises the eyebrows | Creases the forehead to show emotion
Orbicularis oculi (Eyelid muscles) – Opening and closing of the eyes | Involved in the production of tears
Orbicularis oris (Upper lip muscles) – Contributes to the shape of the lips during speech | Opening and closing of the mouth
Platysma (Muscles of the neck) – Pulling down of the mandible that results in the opening of the mouth | Contribution to various facial expressions such as sadness, surprise, and horror
Mechanism of muscle weakness
A person with Bell’s palsy experiences a sudden weakness in the muscles on one side of the face, resulting in facial drooping on one side. This condition is also known as acute peripheral facial palsy of unknown cause, as experts and specialists are yet to find the reason for why certain facial muscles are suddenly weakening. Observations implicate that swelling and inflammation of facial muscle nerves are a possible cause of the condition, others also believe that the body's adverse reaction to viral infections can also be a precursor to the condition.
Other symptoms
Drooling | Headaches | Difficulty in speech | Increased sensitivity to sound in the affected side | Pain around the jaw | Dry eye or excessive tearing in the other eye | Loss of taste