Muscles Flashcards
Occipitofrontalis
Location: Anterior and posterior bellies joined by epicranial aponeurosis
NS: CN VII
A: Elevates eyebrows, retracts scalp
Depressor supercilii
Location: Superficial eyebrow muscle
NS: CN VII
A: Pulls eyebrow downward
Corrugator supercilii
Location: Deep eyebrow muscle
NS: CN VII
A: Pulls eyebrows together
Orbicularis oculi
Location: Palpebral and orbital parts
NS: CN VII
A: Palpebral part: gently closes eyes
Orbital part: tightly closes eyes
Procerus
Location: Most superior nasal muscle
NS: CN VII
A: Pulls eyebrows downward; produces transverse nose wrinkles
Nasalis
Location: Transverse and alar parts
NS: CN VII
A: Transverse part: compresses nares
Alar part: opens nares
Depressor septi nasi
Location: Beneath nose inbetween alar nasalis
NS: CN VII
A: Pulls nose inferiorly opening nares
Superior mouth muscles
- Levator labii superioris alaque nasi
- Levator labii superioris
- Levator anguli oris
- Zygomaticus minor
- Zygomaticus major
Location: Medial to lateral superior mouth muscles
NS: CN VII
A: Smiling muscles
Orbicularis oris
Location: Sphincter of the mouth
NS: CN VII
A: Purses lips; holds lips closed
Risorius
Location: Lateral mouth muscles
NS: CN VII
A: Grimacing; pulls corners of mouth laterally
Buccinator
Location: Cheek muscle
NS: CN VII
A: Presses cheek against molars; resists distension of cheeks when blowing
Inferior mouth muscles
- Mentalis
- Depressor labii inferioris
- Depressor anguli oris
Location: Medial to lateral inferior mouth muscles
NS: CN VII
A: Mouth depressors
Platysma
Location: Flat, broad anterior neck muscle
NS: CN VII
A: Depresses mandible; tenses skin on anterior face and neck
Superior rectus (eye)
O: Common tendinous ring in the optic canal and medial part of superior orbital fissure
I: Sclera, just posterior to the cornea
NS: CN III
A: Elevates, adducts and medially rotates eye
Inferior rectus (eye)
O: Common tendinous ring in the optic canal and medial part of superior orbital fissure
I: Sclera, just posterior to the cornea
NS: CN III
A: Depresses, adducts and laterally rotates eye
Medial rectus (eye)
O: Common tendinous ring in the optic canal and medial part of superior orbital fissure
I: Sclera, just posterior to the cornea
NS: CN III
A: Adducts the eye
Lateral rectus (eye)
O: Common tendinous ring in the optic canal and medial part of superior orbital fissure
I: Sclera, just posterior to the cornea
NS: CN VI
A: Abducts the eye
Superior oblique (eye)
O: Body of sphenoid
I: Sclera, deep to superior rectus
NS: CN IV
A: Abducts, depresses and medially rotates eye
Inferior oblique (eye)
O: Anterior floor of orbit
I: Sclera, deep to lateral rectus
NS: CN III
A: Abducts, elevates and laterally rotates eye
Temporalis
O: Temporal fossa
I: Coronoid process (mandible)
NS: CN V3
A: Elevates and retracts mandible
Masseter
O: Zygomatic arch
I: Ramus of mandible
NS: CN V3
A: Elevates mandible
Medial pterygoid
O: Maxilla (sup) and lateral pterygoid plate (deep)
I: Ramus of mandible
NS: CN V3
A: Bilaterally: protraction/retraction
Unilaterally: ipsilateral movement of jaw
Lateral pterygoid
O: Greater wing (sup) and lateral pterygoid plate (inf.) of sphenoid
I: Neck of mandible (Disc attaches to this)
NS: CN V3
A: Bilaterally: protracts mandible
Unilaterally: ipsilateral movement of jaw
Sternocleidomastoid
O: Mastoid process and superior nuchal line
I: Sternal head: manubrium and sternum
Clavicular head: medial third clavicle
NS: CN XI (Accessory nerve); C2-C3 (pain and proprioception)
A: Unilateral: rotates head contralaterally and laterally tilts head
Bilateral: extends OA; flexes Cx; forward head
Trapezius
O: Superior nuchal line; inion; nuchal ligament; SPs C7-T12
I: Clavicle; acromion; spine of scapula
NS: CN XI (Accessory nerve); C2-C3 (pain and proprioception)
A: Superior: elevate scapulae
Middle: retract scapulae
Inferior: depress scapulae
Levator scapulae
O: Posterior tubercles of C2-C6 TPs
I: Superior angle of scapula
NS: Dorsal scapula nerve (C5); Cx spinal nerves C3- C4
A: Anterior rotation of scapula; tilts glenoid fossa inferiorly
Mylohyoid
O: Mylohyoid line of mandible
I: Body of hyoid
NS: Nerve to mylohyoid (from inferior alveolar nerve - from CN V3)
A: Elevates hyoid, floor of mouth, and tongue during swallowing and speaking
Geniohyoid
O: Inferior mental spine of mandible
I: Body of hyoid
NS: C1 via CN XII (Hypoglossal nerve)
A: Pulls hyoid anterosuperiorly; shortens floor of mouth; widens pharynx
Stylohyoid
O: Styloid process of temporal bone
I: Body of hyoid
NS: Stylohyoid branch of CN VII (Facial nerve)
A: Elevates and retracts hyoid; elongates floor of mouth
Digastric
O: Anterior: digastric fossa of mandible
Posterior: mastoid process of temporal bone
I: Intermediate tendon to body and greater horn of hyoid
NS: Nerve to mylohyoid (anterior); digastric branch of CN VII (Facial nerve) (posterior)
A: Depresses mandible; elevates hyoid during swallowing and speaking
Sternohyoid
O: Manubrium of sternum; clavicle
I: Body of hyoid
NS: C1-C3 by branch of ansa cervicalis
A: Depresses hyoid after elevation during swallowing
Omohyoid
O: Superior border of scapula (has intermediate tendon)
I: Hyoid
NS: C1-C3 by branch of ansa cervicalis
A: Depresses, retracts and steadies hyoid
Sternothyroid
O: Manubrium of sternum
I: Oblique line of thyroid cartilage
NS: C2-C3 by branch of ansa cervicalis
A: Depresses hyoid and larynx
Thyrohyoid
O: Oblique line of thyroid cartilage
I: Body and greater horn of hyoid
NS: C1 via CN XII (Hypoglossal nerve)
A: Depresses hyoid and elevates larynx
Longus colli
O: Anterior tubercle C1; C1-C3 bodies; TPs of C3-C6
I: Bodies of C5-T3; TPs of C3-C5
NS: Ventral rami of C2-C6 spinal nerves
A: Flexes neck with rotation to contralateral side (unilaterally)
Longus capitis
O: Basilar part of occipital bone
I: Anterior tubercles of C3-C6 TPs
NS: Ventral rami of C1-C3 spinal nerves
A: Flexes head
Rectus capitis anterior
O: Anterior to occipital condyle
I: Lateral mass C1
NS: Branches from C1-C2 loop
A: Flexes head
Rectus capitis lateralis
O: Jugular process of occipital bone
I: TP C1
NS: Branches from C1-C2 loop
A: Flexes head
Anterior scalene
O: TPs C3-C6
I: 1st rib
NS: C4-C6 spinal nerves
A: Flexes head
Middle scalene
O: Posterior tubercles TPs C2- C7
I: 1st rib
NS: Ventral rami of Cx spinal nerves
A: Lateral flexion; elevation of 1st and 2nd ribs respectively
Posterior scalene
O: Posterior tubercles of C4- C6
I: 2nd rib
NS: Ventral rami of C7-C8 spinal nerves
A: Lateral flexion; elevation of 1st and 2nd ribs respectively
Rectus capitis posterior minor
O: SP C2
I: Inferior nuchal line of occipital bone (medially)
NS: Suboccipital nerve; greater occipital nerve
A: OA extension
Rectus capitis posterior major
O: Posterior tubercle C1
I: Inferior nuchal line of occipital bone (laterally)
NS: Suboccipital nerve; greater occipital nerve
A: Extension and ipsilateral rotation of head
Obliquus capitis inferior
O: SP C2
I: TP C1
NS: Suboccipital nerve; upper cervical spinal nerves
A: Ipsilateral rotation of head
Obliquus capitis superior
O: TP C1
I: Between superior and inferior occipital lines
NS: Suboccipital nerve; upper cervical spinal nerves
A: Postural muscle
Splenius capitis
O: Ligamentum nuchae; SPs C7- T4
I: Mastoid process; superior nuchal line
NS: C4-C6 spinal nerves
A: Ipsilateral rotation of head; extension and lateral flexion
Splenius cervicis
O: Ligamentum nuchae; SPs T3- T6
I: Posterior tubercles of C1- C3 TPs
NS: C6-C8 spinal nerves
A: Ipsilateral rotation of head; extension and lateral flexion
Spinalis
O: Iliac crest; sacrum; SIJ ligaments; supraspinous ligament
I: Thoracis, cervicis, capitis; SPs in upper Tx, Cx and cranium
NS: Dorsal rami of spinal nerves
A: Bilaterally: extends Vx column; eccentrically controls movement during back flexion
Unilaterally: lateral flexion of Vx column
Longissimus
O: Iliac crest; sacrum; SIJ ligaments; supraspinous ligament
I: Thoracis, cervicis, capitis; ribs between tubercles and angles; TPs in Tx, Cx; mastoid process
NS: Dorsal rami of spinal nerves
A: Bilaterally: extends Vx column; eccentrically controls movement during back flexion
Unilaterally: lateral flexion of Vx column
Iliocostalis
O: Iliac crest; sacrum; SIJ ligaments; supraspinous ligament
I: Lumborium, thoracis, cervicis; angles of lower ribs; Cx TPs
NS: Dorsal rami of spinal nerves
A: Bilaterally: extends Vx column; eccentrically controls movement during back flexion
Unilaterally: lateral flexion of Vx column
Semispinalis
O: TPs C4-T12
I: Thoracis, cervicis, capitis; occipital bone; SPs, 4-6 segments above origin
NS: Dorsal rami of spinal nerves
A: Extension; contralateral rotation
Multifidus
O: Iliac crest; sacrum; aponeurosis of erector spinae; SIJ ligaments; mammillary processes; TPs T1-T3; APs C4- C7
I: SPs 2-4 segments above origin
NS: Dorsal rami of spinal nerves
A: Extension; stabilises vertebrae
Rotatores
O: Tx TPs
I: Lamina 2 segments (longus) or 1 segment (brevis) above
NS: Dorsal rami of spinal nerves
A: Extension; stabilises vertebrae; local extension and rotation
Interspinalis
O&I: Between SPs
NS: Dorsal rami of spinal nerves
A: Extension
Intertransversarii
O&I: Between TPs
NS: Ventral and dorsal rami of spinal nerves
A: Lateral flexion; stabilisation
Levator costarium
O: Tips of TPs C7- T11
I: 2 ribs below in- between tubercle and angle
NS: Dorsal rami of C8-T11
A: Elevate ribs; lateral flexion