The mastoid branch is a continuation of the lateral neck of the sphenoid bone or the body of the sphenoid bone of the temporal bone. The lateral surface of the mastoid branch is convex. In front, the line corresponding to the posterior edge of the ramus is spaced from the inner surface of the temporalis muscle in the direction of the tubercle, forming an angle of the protruding lower border of the canal. The posterior edge of the mastoid branch has an interosseous notch - the site of contact with the wall of the pyramid of the temporal bone (which is divided by the scapula). On the upper edge between the notch and the ear opening there is a fold of the mucous membrane - the tragus (anulus from the Latin anta - “front part”).
To maintain the drainage of pus from the middle ear, the auditory tube opens into the upper middle ear behind the attachment of the stapes to the horizontal process of the malleus, bypassing the eardrum. Thus, in order to break into the eardrum canal, pus must pass through the stones