Extrinsic muscles
Parotido-auricularis
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It is a thin and wide muscle situated on the parotid salivary gland. It is wide below and narrow above.
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Origin: Fascia on the lower part of parotid gland.
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Insertion: Conchal cartilage below the angle of junction of its borders.
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Action: To incline the ear downwards and backwards
Cervico-auricularis
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This muscle is a compound muscle with three parts, namely cervico-auricularis externus, medius and internus, named according to their position at their origin. They are arranged layer by layer.
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Origin: Ligamentum nuchae and cervical fascia.
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Insertion: Medial face of the base of the concha.
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Action: Rotate the ear and draw it backward.
Parieto-auricularis externus
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It is a wide but thin muscle covering the temporalis.
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Origin: Frontal crest, parietal and occipital bones.
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Insertion: Scutiform cartilage and anterior aspect of concha.
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Action: To adduct the concha rotate it forwards to prick the ear
Parieto-auricularis internus
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It is placed partially under the preceding muscle.
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Origin: Parietal bone behind the frontal eminence.
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Insertion: Medial face of the concha.
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Action: To adduct the ear.
Zygomatico-auricularis
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It is made up of two bundles.
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Origin: Zygomatic process of the squamous temporal.
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Insertion: The upper bundle to the scutiform cartilage and the lower one to the front and base of concha.
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Action: To prick the ear.
Temporo- auricularis (Tragicus of horse)
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It is a very thin fasciculus.
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Origin: External auditory process and annular cartilage.
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Insertion: Base of concha.
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Action: To telescope the conchal and annular cartilage and shorten the external acoustic meatus.
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Last modified: Saturday, 15 October 2011, 8:39 AM