Joints of the auditory ossicles (incudomalleolar and incudostapedial)

Study entry

Classification

Two synovial joints between the ossicles of the middle ear: the incudomalleolar (saddle, with a small meniscus) and the incudostapedial (ball-and-socket).

Surfaces

Head of the malleus with the body of the incus, in the epitympanic recess (incudomalleolar); lenticular process, at the tip of the long limb of the incus, with the head of the stapes (incudostapedial). The base of the stapes is attached to the margins of the oval window.

Capsule

The short limb of the incus is attached by a ligament to the posterior wall of the tympanic cavity.

Movements

The chain of ossicles carries the vibration of the tympanic membrane to the oval window: it increases the force about tenfold and decreases the amplitude.

Blood supply

[CHECK: Moore does not describe it in the passages consulted (look in another source).]

Innervation

[CHECK: Moore does not describe it in the passages consulted (look in another source).]

Source: cap. 8, «Huesecillos del oído» (fig. 8-116)

Other structures in this region

• Stylohyoid ligament
• Pterygospinous ligament
• Thyrohyoid membrane (median and lateral thyrohyoid ligaments)
• Median cricothyroid ligament
• Cricothyroid joint
• Cricoarytenoid joint
• Gomphosis (dentoalveolar syndesmosis)
• Temporomandibular joint (TMJ)