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Incus
The ''incus'' (plural incudes) or anvil is a bone in the middle ear. The anvil-shaped small bone is one of three ossicles in the middle ear. The ''incus'' receives vibrations from the ''malleus'', to which it is connected laterally, and transmits these to the ''stapes'' medially. The ''incus'' is so-called because of its resemblance to an anvil ( la, Incus). Structure The incus is the second of the ossicles, three bones in the middle ear which act to transmit sound. It is shaped like an anvil, and has a long and short crus extending from the body, which articulates with the malleus. The short crus attaches to the posterior ligament of the incus. The long crus articulates with the stirrup at the lenticular process. The superior ligament of the incus attaches at the body of the incus to the roof of the tympanic cavity. Function Vibrations in the middle ear are received via the tympanic membrane. The malleus, resting on the membrane, conveys vibrations to the incus. This in tu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ossicles
The ossicles (also called auditory ossicles) are three bones in either middle ear that are among the smallest bones in the human body. They serve to transmit sounds from the air to the fluid-filled labyrinth (cochlea). The absence of the auditory ossicles would constitute a moderate-to-severe hearing loss. The term "ossicle" literally means "tiny bone". Though the term may refer to any small bone throughout the body, it typically refers to the malleus, incus, and stapes (hammer, anvil, and stirrup) of the middle ear. Structure The ossicles are, in order from the eardrum to the inner ear (from superficial to deep): the malleus, incus, and stapes, terms that in Latin are translated as "the hammer, anvil, and stirrup". * The malleus ( la, "hammer") articulates with the incus through the incudomalleolar joint and is attached to the tympanic membrane ( eardrum), from which vibrational sound pressure motion is passed. * The incus ( la, "anvil") is connected to both the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Ear
The middle ear is the portion of the ear medial to the eardrum, and distal to the oval window of the cochlea (of the inner ear). The mammalian middle ear contains three ossicles, which transfer the vibrations of the eardrum into waves in the fluid and membranes of the inner ear. The hollow space of the middle ear is also known as the tympanic cavity and is surrounded by the tympanic part of the temporal bone. The auditory tube (also known as the Eustachian tube or the pharyngotympanic tube) joins the tympanic cavity with the nasal cavity (nasopharynx), allowing pressure to equalize between the middle ear and throat. The primary function of the middle ear is to efficiently transfer acoustic energy from compression waves in air to fluid–membrane waves within the cochlea. Structure Ossicles The middle ear contains three tiny bones known as the ossicles: '' malleus'', '' incus'', and ''stapes''. The ossicles were given their Latin names for their distinctive shapes; they ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Ear
The middle ear is the portion of the ear medial to the eardrum, and distal to the oval window of the cochlea (of the inner ear). The mammalian middle ear contains three ossicles, which transfer the vibrations of the eardrum into waves in the fluid and membranes of the inner ear. The hollow space of the middle ear is also known as the tympanic cavity and is surrounded by the tympanic part of the temporal bone. The auditory tube (also known as the Eustachian tube or the pharyngotympanic tube) joins the tympanic cavity with the nasal cavity (nasopharynx), allowing pressure to equalize between the middle ear and throat. The primary function of the middle ear is to efficiently transfer acoustic energy from compression waves in air to fluid–membrane waves within the cochlea. Structure Ossicles The middle ear contains three tiny bones known as the ossicles: '' malleus'', '' incus'', and ''stapes''. The ossicles were given their Latin names for their distinctive shapes; they ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malleus
The malleus, or hammer, is a hammer-shaped small bone or ossicle of the middle ear. It connects with the incus, and is attached to the inner surface of the eardrum. The word is Latin for 'hammer' or 'mallet'. It transmits the sound vibrations from the eardrum to the '' incus'' (anvil). Structure The malleus is a bone situated in the middle ear. It is the first of the three ossicles, and attached to the tympanic membrane. The head of the malleus is the large protruding section, which attaches to the incus. The head connects to the neck of malleus. The bone continues as the handle (or manubrium) of malleus, which connects to the tympanic membrane. Between the neck and handle of the malleus, lateral and anterior processes emerge from the bone. The bone is oriented so that the head is superior and the handle is inferior. Development Embryologically, the malleus is derived from the first pharyngeal arch along with the '' incus''. It grows from Meckel's cartilage. Function The m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Posterior Ligament Of The Incus
The posterior ligament of the incus is a fibrous band that connects the tip of the short crus of the incus to the fossa incudis, running to the mastoid (posterior wall of the middle ear chamber). The posterior incudal ligament plays an important role in the vibration of the middle ear bones: together with the anterior ligament of the malleus The ligaments of malleus are three ligaments that attach the malleus in the middle ear. They are the anterior, lateral and superior ligaments. The anterior ligament of the malleus also known as Casserio's ligament is a fibrous band that extends ..., it forms a pivotal axis around which the ossicles rotate. This rotation conveys vibrations from the tympanum to the oval window on the bony labyrinth (where they can be transduced into electrical signals transmitted to the nervous system). Human head and neck Ligaments {{ligament-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incudostapedial Joint
Incudostapedial joint is a small, synovial ball-and-socket joint between the '' incus'' (anvil) and the ''stapes'' (stirrup). The joint's function is to transfer vibrations between the two ossicles. The incudostapedial joint lies between the long leg of the incus (long crus, or ''crus longum incudis'') and the head of the ''stapes'' (''caput stapedis''). The long leg moves with the rest of the ''incus'' and a small knob, the lenticular process, articulates with the head of the ''stapes''. Biophysics Although the joint is synovial, it nonetheless allows only for a very limited, linear range of motion. All of the ossicles move almost as a single unit. As the transfer of kinetic energy from the incident sound waves to the perilymph of the inner ear involves a loss of energy, the ossicular system functions to compensate for the loss by decreasing the lever A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or '' fulcrum''. A lever is a rig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Superior Ligament Of The Incus
The superior ligament of the incus is a fibrous band that crosses from the body of the incus to the roof of the tympanic cavity just posterior to the superior ligament of the malleus The malleus, or hammer, is a hammer-shaped small bone or ossicle of the middle ear. It connects with the incus, and is attached to the inner surface of the eardrum. The word is Latin for 'hammer' or 'mallet'. It transmits the sound vibrations f .... Ear Ligaments {{ligament-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Incudomalleolar Joint
The incudomalleolar joint (more correctly called incudomallear joint) or articulatio incudomallearis is a small synovial joint between the malleus (hammer) and the incus (anvil). The joint's function is to transfer vibrations between the ossicles in the middle ear, which is perceived as sound. Contrary to other synovial joints the movement is very limited. All of the ossicles move more or less as a unit, at least at low frequencies. When the eardrum is moved inward due to sound vibrations, transferred through the outer ear The outer ear, external ear, or auris externa is the external part of the ear, which consists of the auricle (also pinna) and the ear canal. It gathers sound energy and focuses it on the eardrum (tympanic membrane). Structure Auricle Th ..., it transmits to the handle or manubrium of the malleus which is connected to the ear drum. The head of the malleus (caput mallei) moves with it and transfers energy/movement to the corpus of the incus (corpu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stapes
The ''stapes'' or stirrup is a bone in the middle ear of humans and other animals which is involved in the conduction of sound vibrations to the inner ear. This bone is connected to the oval window by its annular ligament, which allows the footplate to transmit sound energy through the oval window into the inner ear. The ''stapes'' is the smallest and lightest bone in the human body, and is so-called because of its resemblance to a stirrup ( la, Stapes). Structure The ''stapes'' is the third bone of the three ossicles in the middle ear and the smallest in the human body. It measures roughly , greater along the head-base span. It rests on the oval window, to which it is connected by an annular ligament and articulates with the '' incus'', or anvil through the incudostapedial joint. They are connected by anterior and posterior limbs ( la, crura). Development The ''stapes'' develops from the second pharyngeal arch during the sixth to eighth week of embryological life. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alessandro Achillini
Alessandro Achillini (''Latin'' Alexander Achillinus; 20 or 29 October 1463 (or possibly 1461)2 August 1512) was an Italian philosopher and physician. He is known for the anatomic studies that he was able to publish, made possible by a 13th-century edict putatively by Emperor Frederick II allowing for dissection of human cadavers, and which previously had stimulated the anatomist Mondino de Luzzi (c. 1270 – 1326) at Bologna. Biography Achillini was born in Bologna and lived the majority of his life there. He was the son of Claudio Achillini, member of an old family of Bologna. He was celebrated as a lecturer both in medicine and in philosophy at Bologna and Padua, and was styled the second Aristotle. He was of a very simplistic nature. He was unskilled in the arts of adulation and double-dealing to such a degree that his most witty and imprudent students often regarded him as an object of ridicule, even though they honored him as a teacher. He also possessed quite a lively ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tympanic Cavity
The tympanic cavity is a small cavity surrounding the bones of the middle ear. Within it sit the ossicles, three small bones that transmit vibrations used in the detection of sound. Structure On its lateral surface, it abuts the external auditory meatus ear canal from which it is separated by the tympanic membrane (eardrum). Walls The tympanic cavity is bounded by: * Facing the inner ear, the medial wall (or ''labyrinthic wall'', ''labyrinthine wall'') is vertical, and has the oval window and round window, the promontory, and the prominence of the facial canal. * Facing the outer ear, the lateral wall (or ''membranous wall''), is formed mainly by the tympanic membrane, partly by the ring of bone into which this membrane is inserted. This ring of bone is incomplete at its upper part, forming a notch (notch of Rivinus), close to which are three small apertures: the "iter chordæ posterius", the petrotympanic fissure, and the "iter chordæ anterius". The iter chordæ posterius ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auditory System
The auditory system is the sensory system for the sense of hearing. It includes both the sensory organs (the ears) and the auditory parts of the sensory system. System overview The outer ear funnels sound vibrations to the eardrum, increasing the sound pressure in the middle frequency range. The middle-ear ossicles further amplify the vibration pressure roughly 20 times. The base of the stapes couples vibrations into the cochlea via the oval window, which vibrates the perilymph liquid (present throughout the inner ear) and causes the round window to bulb out as the oval window bulges in. Vestibular and tympanic ducts are filled with perilymph, and the smaller cochlear duct between them is filled with endolymph, a fluid with a very different ion concentration and voltage. Vestibular duct perilymph vibrations bend organ of Corti outer cells (4 lines) causing prestin to be released in cell tips. This causes the cells to be chemically elongated and shrunk ( somatic motor), and h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
