Muscles Flashcards
Which nerve are the muscles of Facial Expression innervated by?
Facial nerve (CN VII)
Occipitofrontalis - facts
- 2 bellies: occipital and frontal
joined via the epicranial aponeurosis
Occipitofrontalis - Origin/Insertion
Origin:
Frontal belly - epicranial aponeurosis
Occipital belly - lateral 2/3 of superior nuchal line
Insertion:
Frontal belly - skin and subcutaneous tissue of eyebrows and forehead
Occipital belly - epicranial aponeurosis
Occipitofrontalis - Action
elevates eyebrows, wrinkles skin on forehead, retracts scalp
Orbicularis Oculi - facts
Sphincter shaped muscle
two parts - palpebral par (inner), orbital part (outer)
Orbicularis Oculi - Origin/Insertion
Origin:
medial orbital margin, medial palpebral ligament, lacrimal bone
Insertion:
skin around margin of orbit, superior and inferior tarsal plates in eyelids
Orbicularis Oculi - Action
closes eyelids
palpebral part: gently
orbital part: tightly
Buccinator - Origin/Insertion
Origin:
alveolar processes of maxilla and mandible
Insertion:
angle of mouth and orbicularis oris
Buccinator - Action
presses cheek against molar teeth, resists distension of cheeks when blowing
Orbicularis Oris - facts
Sphincter of mouth
Orbicularis Oris - Origin/Insertion
Origin:
maxilla and mandible bones, angles of mouth
Insertion:
mucous membranes of lips
Orbicularis Oris - Action
holds lips closes, compresses and protrudes lips
Platysma - facts
contained within the subcutaneous tissue of the neck
Platysma - Origin/Insertion
Origin:
subcutaneous fascia of the supra and infraclavicular regions
Insertion:
mandible, skin of cheek and lower lip
Platysma - Action
depresses mandible, tenses skin of inferior face and neck
Temporalis - PA & DA
PA:
floor of temporal fossa, up to the inferior temporal line, deep surface temporal fascia
DA:
coronoid process of the mandible, anterior ramus
Temporalis - N/S & Action
N/S:
CN V3 mandibular br. of trigeminal nerve
Action:
elevates mandible, posterior fibre retract the mandible
Masseter - PA & DA
PA:
Zygomatic bone and zygomatic arch
DA:
angle and lateral side of ramus of the mandible
Masseter - N/S & Action
N/S:
CN V3 mandibular br. of trigeminal nerve
Action:
elevated mandible, assists in protusion
Lateral Pterygoid - PA & DA
PA:
greater wing of sphenoid, lateral surface of lateral pterygoid plate
DA:
Neck of mandibular br. of trigeminal nerve
Lateral Pterygoid - N/S & Action
N/S:
CN V3 mandibular br. of trigeminal nerve
Action:
bilat - protrudes mandible, depress chin
unilat - moves jaw to contralateral side
Medial Pterygoid - PA & DA
PA:
medial surface of lateral pterygoid plate, palatine & maxillary bone
DA:
medial surface of the mandibular ramus
Medial Pterygoid - N/S & Action
N/S:
CN V3 mandibular br. of trigeminal nerve
Action:
elevates mandible and assists in protrusion
unilat - produces grinding movements
Sternocleidomastoid - IA & SA
IA:
Sternal head - manubrium
Clavicular head - medial 1/3 of the clavicle
SA:
Mastoid process of the temporal bone
Sternocleidomastoid - N/S & Action
N/S:
Accessory nerve: CN XI (motor) and spinal nerves C2/3 (pain and proprioception
Action:
Bilat - anterior translation of the head
unilat - ipsilateral sidebending, contralateral rotation
Trapezius - PA & DA
PA:
medial 1/3 sup nuchal line, EOP, nuchal ligament, SPs of C7-T12 vertebrae
DA:
Lat 1/3 of clavicle, acromion and spine of the scapula
Trapezius - N/S & Action
N/S:
Spinal accessory nerve CN XI (motor)
C3/4 spinal nerves (sensory, pain and proprioception
Action
Sup: Elevates scap.
Mid: Retracts scap
Low: Depresses Scap
Which muscles are included in the Suprahyoid muscles?
Mylohyoid, Geniohyoid, Stylohyoid, Digastric
Which muscles are included in the Infrahyoid muscles?
Sternohyoid, Omohyoid, Sternothyroid, Thyrohyoid
Mylohyoid - O & I
O: mandible
I: hyoid
Geniohyoid muscles - O & I
O: hyoid
I: back of the chin
Stylohyoid - O & I
O: Styloid process
I: hyoid
Digastric - O & I
O: posterior belly - mastoid process, anterior belly - mandible
I: Hyoid
Sternohyoid - O & I
O: sternum
I: hyoid
Omohyoid - O&I
O: Scapula
I: hyoid
Sternothyroid - O & I
O: Sternum
I: Thyroid cartilage
Thyrohyoid - O & I
O: thyroid cartilage
I: hyoid
Where are the prevertebral muscles located?
lie in the floor of the anterior and posterior triangles, under the prevertebral fascia
Anterior muscles of the neck and main function
Longus colli
Longus capitis
Rectus capitis anterior
Anterior scalene
flexion of the head and neck
Longus colli
long muscle of the neck
Longus capitis
long muscle of the head, fibres are broad and thick superiorly and narrow inferiorly, fibres pass superiomedially
Rectus capitis anterior
straight, attaching to the head, anterior
Lateral muscles of the neck
Rectus capitis lateralis, splenius capitis, middle scalene, posterior scalene, levator scapulae
Middle Scalenes - SA & IA & Action
SA:
Posterior tubercles of TPs of C5-C7
IA:
1st rib, posterior to the subclavian groove
Action:
Sidebending of neck, elevation of 1st rib during forced respiration
Posterior Scalenes - SA, IA & Action
SA:
Posterior tubercles of Tps of C5-7
IA:
External border of 2nd rib
Action:
Sidebending of neck, elevation of 2nd rib during forced respiration
Levator Scapulae - SA, IA & Action
SA:
Posterior tubercles of TPs C1-4 vertebrae
IA:
Medial border of the scapula, superior to the spine of the scapula
Action:
Elevates scapula and downwardly rotates it
Suboccipital Triangle - Contents
suboccipital nerve
vertebral artery
Suboccipital Triangle - Boundaries
Superomedial - rectus capitis posterior major
Superolateral - Obliquus capitis superior
Inferolateral - Obliquus capitis inferior
Suboccipital triangle - roof and floor
Roof - Semispinalis capitis
Floor - Posterior atlanto-occipital membrane and posterior arch of vertebra C1
Which muscles are in the Superficial Group (extrinsic)
Latissimus Dorsi, Rhomboids, Lev Scap, Trapezius
Which muscles are in the intermediate Group (extrinsic)
Serratus posterior superior, serratus posterior inferior
Which muscles are in the deep group (intrinsic) - Superficial
Splenius capitis, splenius cervicis
Which muscles are in the deep group (intrinsic) - Intermediate
Erector Spinae - Iliocostalis, Longissimus, Spinalis
Which muscles are in the deep group (intrinsic) - deep
major: Rotatores, Multifidis, Semispinalis
minor: Interspinalis, Intertransversarii, levator costarum
Latissimus Dorsi - PA & DA
PA: SP’s T7-T12, iliac crest, T/L Fascia
DA: Floor of bicipital groove
Latissimus Dorsi - N/S & A
NS: thoracodorsal n (C6-8)
A: adduct, extend, IR humerus
Rhomboid Major - PA & DA
PA: maj – T2-T5 SP’s; min – C7-T1 SP’s, nucal lig.
I: medial border scapula (minor above spine of scapula/major below spine of scapula)
Rhomboid Major/Minor - N/S & A
NS: dorsal scapula (C4-5)
A: retraction of scapula
Levator Scapulae - PA & DA
PA: C1-C4 TP’s
DA: superior angle of scap.
Levator Scapulae - N/S & A
NS: dorsal scapula (C5)
A: Sup: Elevates scap.
Trapezius - PA &DA
PA: C7-T12 SP’s, nuchal line & lig.
DA: lat 1/3 clavicle, acromion, spine of scap.
Trapezius - N/S & A
NS: M: CN 11 (acc.) + S: C3/4 spinal ns.
A: Sup: Elevates scap.; Mid: Retracts scap.; Low: Depresses Scap
Serratus posterior superior
- deep to rhomboids
- thin
- help with respiration
Serratus posterior inferior
- deep to latissimus dorsi
- helps with respiration
Splenius capitis & cervicis - N/S & A
N/S: posterior rami of spinal nerves
A: extends head & neck (bilat), lat flex & rotation (unilat)
Erector Spinae - PA &DA
PA (common): posterior iliac crest, posterior sacrum, posterior median crest
DA: Spinalis - spinous process; Longissimus - transverse process, mastoid process; Iliocostalis: b/w ribs
Erector Spinae - N/S & A
N/S: posterior rami of spinal nerves
A: extension of Tx/LX, ipsilateral sidebending
Deep Group (intrinsic, major) - IA & SA & N/S & facts
IA: TP’s
SA: SP’s
- running from superficial to deep (rotatores 1-2, multifidis 2-4, semispinalis 4-6)
N/S: posterior rami of spinal nerves
Deep group (intrinsic, minor) - N/S
all posterior rami of spinal nerves
Intertransversarii - anterior and posterior rami of spinal nerves
