Molecular Any injury sustained from blunt force, which may be related to MVAs, or mishaps, falls or jumps, blows or crush injuries from animals, blunt objects or unarmed assailants. Cf Penetrating trauma. A wound in which the surface of the skin remains intact, caused by impact or collision with a blunt object, e.g., an automobile fender.
Mastoiditis occurs when ear infections cause infection in the mastoid bone. The mastoid bone can be found directly behind the ear. Mastoiditis causes the area behind the ear to swell and protrude out of the skin. The bump behind ear is accompanied with fever, ear pain, hearing loss and ear redness.
Middle ear. Also known as the tympanic cavity, the middle ear is an air-filled, membrane-lined space located between the ear canal and the Eustachian tube, cochlea, and auditory nerve. The eardrum separates this space from the ear canal. The area is pressurized. The eardrum acts as a natural boundary between the middle ear and the ear canal. Pressure in the middle ear is maintained through the Eustachian tubes, which are closed when not in use. Each time a person swallows, the Eustachian tubes open and allow fresh air to enter into the tympanic cavity.