Question

multiple choice 2 points

the incus articulates with which bone(s)?

• stapes
• malleus
• malleus and stapes
• malleus, stapes, and tympanic
• malleus, stapes, and temporal

Explanation:

Identify the anatomical structure

The question asks about the articulations of the incus (anvil), which is the middle bone of the three auditory ossicles located in the tympanic cavity of the middle ear.

Analyze the connections of the incus

The auditory ossicles form a chain that transmits sound vibrations from the tympanic membrane to the oval window.

• The malleus (hammer) is attached to the tympanic membrane and articulates with the incus.
• The incus (anvil) articulates with both the malleus laterally and the stapes medially.
• The stapes (stirrup) articulates with the incus and its base fits into the oval window of the inner ear.

Evaluate the joint classifications

Using our understanding of Joint Classification and Structural Joints, we know that these connections (the incudomalleolar and incudostapedial joints) are synovial joints. The incus does not directly articulate with the temporal bone or the tympanic bone; it is suspended in the middle ear cavity by ligaments and connected only to the other two ossicles.

Determine the correct option

Since the incus articulates directly with both the malleus and the stapes, the correct choice is "Malleus and stapes".

Answer:

• Stapes
• Malleus
• Malleus and stapes (Correct answer)
• Malleus, stapes, and tympanic
• Malleus, stapes, and temporal