This site is targeted at medical and radiology professionals, contains user contributed content, and material that may be confusing to a lay audience. Use of this site implies acceptance of our Terms of Use.

Malleus

Dr Frank Gaillard et al.

The malleus (from latin for hammer) is the lateral most ossicle, located between the tympanic membrane and the incus (from the latin for anvil). It consists of a head, neck, and three processes (manubrium (handle), anterior and lateral processes).

The head is oval in shape, and articulates posteriorly with the incus by a small facet joint. Its appearance on axial CT is that of a ball of ice cream on a cone (the incus). The facet for articulation with the incus is saddle shape, constricted near the middle, and consists of an upper larger and lower smaller part, which form nearly a right angle with each other.

The neck is the narrow contracted part just beneath the head; below it, is a a prominence, to which the various processes are attached.

The manubrium mallei (handle) is connected by its lateral margin with the tympanic membrane. It is directed downward, medialward, and backward; it decreases in size toward its free end, which is curved slightly forward, and flattened transversely. On its medial side, near its upper end, is a slight projection, into which the tendon of the tensor tympani muscle is inserted.

The anterior process is a delicate spicule, which springs from the eminence below the neck and is directed forward to the petrotympanic fissure, to which it is connected by ligamentous fibers.

The lateral process is a slight conical projection, which springs from the root of the manubrium; it is directed laterally, and is attached to the upper part of the tympanic membrane and, by means of the anterior and posterior malleolar folds, to the extremities of the notch of Rivinus.