Question

A student had his jaw locked while yawning. Which of the following muscles is attached to the articular disc of the temporomandibular joint?

• A. Lateral pterygoid
• B. Temporalis
• C. Medial pterygoid
• D. Masseter

Answer 1

The Correct Option is A

The temporomandibular joint (TMJ) is a complex structure that allows mandibular movements such as opening and closing the mouth. The muscles associated with the TMJ play distinct roles in these movements. The question asks which muscle is attached to the articular disc of the TMJ. Let's evaluate each option:

• Lateral pterygoid: This muscle is the correct answer. The superior head of the lateral pterygoid muscle directly attaches to the articular disc and the joint capsule of the TMJ. This attachment helps in moving the disc anteriorly during jaw opening and is crucial in coordinating mandibular movements.
• Temporalis: The temporalis muscle is primarily responsible for elevating and retracting the mandible. It originates from the temporal fossa and inserts onto the coronoid process of the mandible but does not attach to the articular disc.
• Medial pterygoid: This muscle assists in elevation and side-to-side movement of the mandible. It does not attach to the articular disc; rather, it primarily connects to the medial surface of the ramus of the mandible.
• Masseter: One of the main muscles responsible for the elevation of the mandible, the masseter attaches from the zygomatic arch to the lateral surface of the mandible but does not connect to the articular disc.

Therefore, the lateral pterygoid muscle is uniquely associated with the articular disc of the TMJ, facilitating jaw movements. This makes it the correct answer to the question.