Muscles Practical: HEAD, NECK ,THORAX, ABDOMEN

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Buccinator

Location: deep flesh of the cheek

Origin: alveolar process and Mandible

Insertion: Orbicularis oris

Action: Compresses the cheek against the teeth; assists in chewing.

Innervation: cranial nerve VII

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Mentalis

Origin: mandible below the incisors

Insertion: skin of the chin

Action: Wrinkles the chin (protrudes the lower lip)

Innervation: facial nerve (CN VII)

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Orbicularis Oris

Origin: Maxilla and Mandible; Fibers blend with Fibers of other facial muscles

Insertion: Skin around the mouth

Action: Closes Lips

Innervation: facial nerve

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Risorius

Origin: Fascia overlying the parotid gland, the masseter muscle, and/or the platysma muscle.

Insertion: modiolus

Action: Pulls the angle of the mouth laterally and slightly superiorly (smile)

Innervation: Facial Nerve

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Zygomatic Major

Origin: zygomatic bone

Insertion: skin of the corner of the mouth

Action: Raises the lateral corners of the mouth (smile)

Innervation: Facial nerve

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Zygomatic Minor

Origin: zygomatic bone

Insertion: skin of the corner of the mouth

Action: Raises the lateral corners of the mouth (smile)

Innervation: Facial nerve

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Orbicularis Oculi

Origin: Frontal and maxillary bones

Insertion: tissue of the eye

Action: Closes the eyelids and aids in blinking.

Innervation: Facial nerve (cranial nerve VII)

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Occiptiofrontalis

Frontal Belly

Origin: Epicranial aponeurosis

Insertion: Skin of eyebrows & root of nose

Action: Raises eyebrows

Intervation: Facial nerve

Occipital Belly

Origin: Occipital and temporal bones

Insertion: epicranial aponeurosis

Action: pulls scalp posteriorly

Innervation: Facial nerve

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Temporoparietalis

Origin: temporal fascia

Insertion: galea aponeurotica

Action: pulls the scalp upward or laterally

Innervation: Cranial Nerve VII

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Temporalis

Origin: Temporal fossa

Insertion: Coronoid process

Action: Closes Jaw

Innervation: Trigeminal nerve

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Masseter

Origin: zygomatic arch and bone

Insertion: angle and ramus of mandible

Action: Prime mover of jaw closure

Innervation: Trigeminal nerve

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Digastric

Origin: lower margin of mandible, and mastoid process

Insertion: hyoid bone

Action: Opens mouth and depress mandible (shallowing)

Innervation: cranial V and VII

Mylohyoid

Geniohyoid

omohyoid (superior belly)

Sternohyoid

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Sternocleidomastoid

origin: Sternal and Clavicular head

Insertion: Mastoid process of the temporal bone and superior nuchal line.

Action: rotates head and flexes neck.

Innervation: Cranial XI and C2 and C3

Sternothyroid

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External Intercostals

origin: inferior border of rib above

insertion: superior border of rib below

action: pulls ribs toward one another

innervation: intercostal nerves

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Internal Intercostals

origin: superior border of rib below

insertion: inferior border of rib above

action: pull ribs together and depress rib cage

innervation: intercostal nerves

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Pectorallis Major

origin: sternal end of clavicle, sternum, ribs, oblique muscle

insertion: fibers converge of the intertubercular sulcus of the humerus

action: adducts and medially rotates arm

Innervation: lateral and medial pectoral nerves ( C5-C8 and T1)

pectoralis minor

serratus anterior

subclavius

External Oblique

internal oblique

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Transverse Abdominus

Origin: inguinal ligament, lumbar fossa, cartilages of ribs, iliac crest

Insertion: Linea Alba, pubic crest

Action: compresses abdomen

Innveration: Intercostal nerves ( T7-12) and L1

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Rectus Adbominus

Origin: pubic crest and symphysis

Insertion: xiphoid process and costal cartilage from ribs 5-7

Action: flex and rotate lumbar region of vertebrae

Innveration: intercostal nerves (T5 or T7-12)