A 3-month-old boy is brought to the office for follow-up due to a unilateral cleft lip and palate. The patient has been doing well feeding with specialized bottle nipples and is gaining weight. As part of his multidisciplinary care, the parents are told that he will need to be monitored for ear infections and hearing loss. This is because the patient most likely has dysfunction of which of the following muscles?

Question

A 3-month-old boy is brought to the office for follow-up due to a unilateral cleft lip and palate.  The patient has been doing well feeding with specialized bottle nipples and is gaining weight.  As part of his multidisciplinary care, the parents are told that he will need to be monitored for ear infections and hearing loss.  This is because the patient most likely has dysfunction of which of the following muscles?

Quizplus · Accepted Answer

11ec160b_356a_1acf_9249_bd35cba8b68f_MD0001_00 This patient has a cleft lip and palate, which can lead to problems with feeding, speech, and orthognathic (ie, jaw) development. Children with cleft palate often have recurrent otitis media due to eustachian tube dysfunction. The muscles primarily responsible for opening the eustachian tube include the tensor veli palatini and the levator veli palatini. The levator veli palatini arises from the petrous portion of the temporal bone and medial part of the eustachian tube. Its fibers insert into the superior portion of the palatine aponeurosis (soft palate) and interdigitate in the midline with the contralateral muscle fibers. It elevates the soft palate during swallowing to prevent food from refluxing into the nasopharynx; contraction also opens the eustachian tube. With cleft palate, levator veli palatini insertion is no longer stable, so contraction does not lead to force on the eustachian tube. (Choice A) The lateral pterygoid muscles depress the mandible (ie, open the jaw). They are not impacted in cleft lip or palate. (Choice C) The orbicularis oris encircles the mouth, acting as a sphincter to close the mouth and pucker the lips. In cleft lip, it does not form a complete circle, but inserts into the base of the nose on either side of the cleft; however, it does not impact the function of the eustachian tube. (Choice D) The stapedius muscle is innervated by the facial nerve (CN VII). It arises from the wall of the tympanic cavity and inserts on the neck of the stapes bone. It functions to stabilize the stapes. Contraction causes dampening of sound transmission in response to loud noises. It does not open the eustachian tube. (Choice E) The superior pharyngeal constrictor forms portions of the posterior and lateral oropharyngeal walls. Contraction propels food and liquid inferiorly into the esophagus during swallowing. Together with the levator veli palatini, it elevates the palate to seal the nasal cavity during swallowing. Although both functions are impaired in cleft palate, the superior pharyngeal constrictor does not play a direct role in opening the eustachian tube. Educational objective: Patients with cleft palate are at increased risk of chronic or recurrent acute otitis media, partly because of dysfunction of the muscles (eg, levator veli palatini) that contract against the soft palate to open the eustachian tube.

A 3-Month-Old Boy Is Brought to the Office for Follow-Up