Axial Skeletal Muscles Flashcards
Pectorals Major
O: clavicular head- medial 1/2 clavicle
Sternal head- sternum and costal cartilages #1-7
I: lateral lip of bicipital groove
A: FLEXION, adduction & medial rotation of the arm @ GH jt
Horizontal adduction of arm @ GH jt
N: medial & lateral pictorial nerves
A: thoraco-acromial artery (branch of axillary)
Trapezius
O: upper- external occipital protuberance, medial 1/3 nuchal ligament, spinous process C7.
Middle- spinous process of T1-T5.
Lower- spinous process of T6- T12
I: Upper-acromion & lateral clavicle.
Middle- acromion and spine of scapula
Lower: root of spine of scapula
A: all 3 fibers retract the scapula at the scapulacostal jt.
Upper- elevate the scapula @ scapulacostal jt
Middle- retract the scapula @ scapulacostal jt
Lower- depress the scapula @ scapulacostal jt
N: spinal accessory nerve (cranial nerve 11)
A: transverse cervical & dorsal scapular artery
Pectoralis Minor
O: ribs #3-5
I: coracoid process of scapula
A: protraction & depression of scapula @ the scapulocostal jt
Elevates ribs #3-5 @ sternocostal & costal spinal jts
N: medial & lateral pictorial nerves
A: thoraco-acromial artery (branch of the axillary)
Serratus Anterior
O: anterior portion of ribs #1-9
I: anterior surface of the medial border of the scapula
A: prostration and upwards rotation of the scapula @ scapulacostal jt
N: long thoracic nerve
A: dorsal scapular (subclavian) & lateral thoracic artery (axillary)
Subclavius
O: 1st rib
I: middle of inferior surface of clavicle
A: depresses clavicle @ sternoclavicular jt.
Elevates 1st rib @ sternocostal and costalspinal jts
N: brachial plexus (subclavian C5 & C6)
A: suprascapular & branch from axillary
External Intercostals
O: inferior border of ribs# 1-11
I: superior surface of rib below origin.
(From anterior rib all the way around to vertebrae)
A: elevatin of ribs #2-12 @ sternocostal & costalspinal jts, (during inspiration)
N: intercostal nerves
A: anterior & posterior intercostal nerves
Internal Intercostals
O: superior border of ribs 2-12
I: inferior surface of rib above origin point.
A: depresses ribs #1-11 @ sternocostal & costalspinal jts. (During expiration)
N: intercostal nerves
A: anterior & posterior intercostal arteries.
Innermost Intercostals
O: interior of superior surface of rib below insertion
I: interior of inferior surface of rib above origin
A: depresses ribs #1-11 @ sternocostal & costalspinal jts (during expiration)
N: intercostal nerves
A: anterior & posterior intercostal arteries
Transversus Thoracis
Sternocostalis
O: internal surface of sternum, xiphoid process & costal cartilages
I: internal surfaces of costal cartilages #2-5
A: depresses ribs #2-5 @ sternocostal & costalspinal jts (during expiration)
N: intercostal nerves
External Obliques
O: pubic bone (crest & tubercle), anterior iliac crest & abdominal aponeurosis
I: inferior border of ribs #5-12
A: Flexion, lateral Flexion & contralateral rotation of the trunk @ spinal jts.
Posterior pelvic tilt
N: intercostal nerves (ventral rami T7-T12)
A: posterior intercostal, sub costal, inferior epigastric & deep circumflex iliac arteries
Internal Obliques
O: inguinial ligament, pelvic crest, thoraco lumbar (TL) fascia
I: ribs #10-12, abdominal aponeurosis
A: Flexion, lateral Flexion & ipsilateral rotation of the trunk @ spinal jts
Posterior pelvicl tilt
N: intercostal nerve (ventral rami T7-T12)
A: posterior intercostal, us costal, inferior epigastric & deep circumflex iliac arteries
Rectus Abdominus
O: pubis (symphysis & crest)
I: xiphoid process, costal cartilage of ribs #5-7
A: Flexion of the trunk @ spinal jts
Posterior pelvic tilt
N: Intercostal nerves (ventral rami T5-T12)
A: superior & inferior epigastric, posterior Intercostals
Transverse Abdominus (Corsette or cumberbun muscle)
O: inguinal ligaments, iliac crest, TL fascia, costal cartilage
I: abdominal aponeurosis
A: compresses the abdominopelvic cavity
N: intercostal nerves (ventral rami T7-L1)
A: posterior intercostal, us costal, inferior epigastric, deep circumflex iliac
Pyramidalis
20% of people do not have this muscle
O: Anterior portion of pubic crest
I: distal 1/3 of line of alba
A: tenses the line of alba during Flexion of the trunk @ spinal jts.
Posterior pelvic tilt
N: sub costal nerve
A: superior, inferior gastric & posterior intercostal
Diaphragm
O: Lumbar spine (L1-L3), ribs #7-12 (internal surface) & their costal cartilages, sternum (xiphoid process)
I: central tendon of diaphragm
A: increases the volume of the thoracic cavity via abdominal breathing. (During inspiration)
N: phrenic nerve
A: branches of the aorta & internal thoracic artery
Psoas Major
O: vertebral bodies, transverse processes & discs from T12-L5
I: lesser trochanter of femur (merges with iliacus)
A: flexion & lateral rotation of the thigh @ the hip jt. Flexion & lateral flexion, of the trunk @ the spinal jts. Anterior pelvic tilt.
N: lumbar plexus
A: lumbar arteries
Psoas minor
Missing in 40% of people
O: bodies, discs & transverse processes of T12-L1
I: pubis (pectineal line)
A: Flexion of the trunk @ the spinal jts, posterior pelvic tilt
N: L1 spinal nerve
A: lumbar arteries, common iliac arteries
Iliacus
O: anterior surface of the internal ilium (upper 2/3 iliac fossa, AIIS & sacral ala)
I: lesser trochanter of femur (merges with Psoas major)
A: flexion & lateral rotation of the thigh @ the hip jt. Anteriorelvic tilt.
Splenius Capitis
O: inferior part of nuchal ligament & spinous processes of C7-T4
I: mastoid process & lateral 1/3 of superior nuchal line of occiput.
A: extention, lateral Flexion & ipsilateral rotation of the head @ neck and spinal jts.
N: cervical spine
A:
occipital artery
Splenius Cervicis
O: spinous process of T3-T6 I: transverse process of C1-C3 A: extension, lateral flexion & ipsilateral rotation of neck @ spinal jts. N: cervical spinal A: occipital artery
Suboccipitals - Rectus Capitis Posterior Minor
O: posterior tubercle of C1 (atlas)
I: medial 1/2 of inferior nuchal line of occiput
A: extention & protraction of the head @ CO/C1 jt (occiput and c1)
N: suboccipital nerve
A: occipital artery (& vertebral)
Suboccipitals- Rectus Capitis Posterior Major
O: spinous process of C2 (axis) I: lateral 1/2 of inferior nuchal line of occiput A: extension of head @ CO/C1 jt N: suboccipital nerve A: occipital artery (& vertebral)
Suboccipitals- Obliquus Capitus Inferior
O: spinous process of C2 (axis) I: transverse process of C1 (atlas) A: ipsilateral rotation of the atlas @ C1/C2 jt N: suboccipital nerve A: occipital artery (& vertebral)
Suboccipitals- Obliquus Capitus Superior
O: transverse process of C1 (atlas)
I: occiput between superior & inferior nuchal lines
A: protraction & contralateral rotation of the head @ CO/C1 jt
N: suboccipital nerve
A: occipital artery (&vertebral)
Platysma
O- subcutaneous fascia of pectoralis & deltoid.
I- mandible & subcutaneous fascia of lower face
A- draws the skin of the superior chest and neck up. Creates the ridges of the neck.
N- facial nerve
A- facial artery
Sternocleidomastoid
O- 2 heads: Sternal head- manubrium
Clavicular head- medial 1/3 of clavicle
I- mastoid process of temporal bone & lateral 1/3 of superior nuchal line of occiput.
A- Flexion of the lower neck @ spinal jts. Extention of the head & upper neck @ spinal jts. Lateral Flexion & contralateral rotation of head & neck @ spinal jts.
N- spinal accessory nerve (CN11). Same as traps!
A- occipital & auricular arteries.
Anterior Scalenes
O- transverse processes of C3- C6 (anterior tubercle)
I- rib#1
A- Flexion & lateral Flexion of the neck @ spinal jts. Elevation of rib#1 @ sternocostal & costalspinal jts
N- cervical spinal nerves (ventral rami)
A- cervical artery
Middle Scalenes
O- transverse processes of C2-C7 (posterior tubercle)
I- rib #1
A- Flexion and lateral Flexion of the neck @ spinal jts. Elevation of rib #1 @ costalspinal & sternocostal jts.
N- cervical spinal nerves (ventral rami)
A- cervical artery (ascending)
Posterior Scalenes
O- transverse processes of C5-C7 (posterior tubercle)
I- rib#2
A- lateral Flexion of the neck @ spinal jts. Elevation of rib #2 @ costalspinal & sternocostal jts.
N- cervical spinal nerves (ventral rami)
A- cervical artery (transverse)
Rectus Capitis anterior
O- transverse process of C1
I- anterior foramen magnum of the occiput
A- lateral Flexion of head @ C0/C1 jt. (Opposer to the Rectus Capitus posterior min & major)
N- cervical spinal nerves (ventral rami)
A- vertebral artery
Rectus Capitis lateralis
O- transverse process of C1 I- jugular process of the occiput A- lateral Flexion of head @ C0/C1 N- cervical spinal nerve (ventral rami) A- vertebral artery
Longus colli (prevertebral)
3 parts - superior, inferior oblique, vertical
O- vertebral bodies & transverse processes of C3-T3
I- vertebral bodies & transverse processes of C1-C6
A- Flexion of the neck @ spinal jts
N- cervical spinal nerves (ventral rami)
A- vertebral & inferior thyroid artery
Longus Capitus (prevertebral)
O-transverse processes of C3-C5 I- anterior to foramen magnum on the occiput A- Flexion of the neck @ spinal jts N- cervical spinal nerves (ventral rami) A- vertebral & inferior thyroid artery
Mylohyoid
O- inner surface of mandible, myohyoid line
I- hyoid
A- elevates the hyoid, depresses the mandible @ the TMJ, Flexion of the head & neck @ spinal jts
N- trigeminal nerve (CN 5)
A- inferior alveolar nerve
Geniohyoid - deep to mylohyoid
O- inner surface of mandible, inferior mental spine
I- hyoid
A- elevates the hyoid, depressed the mandible @ the TMJ, flexion of the head & neck @ spinal jts
N- hypoglossal nerve (CN12)
A- lingual artery
Digastric
2 bellies
O- posterior: mastoid notch of temporal bone
Anterior: digastric fossa of mandible
I- posterior: hyoid bone via central tendon
Anterior: hyoid bone via central tendon
A- elevates the hyoid , depresses the mandible @ the TMJ, flexion of the head and neck @ spinal jts
N- anterior: trigeminal nerve (CN5)
Posterior: facial nerve (CN7)
A: occipital, posterior auricular & facial arteries
Stylohyoid
O- Styloid process of the temporal bone I- hyoid A- elevates the hyoid N- facial nerve (CN7) A- occipital, posterior auricular & facial arteries
Thyrohyoid
O- thyroid cartilage I- hyoid A- depresses the hyoid, Flexion of the head & neck @ spinal jts N- hypoglossal nerve (CN12) A- superior thyroid artery
Omohyoid
2 bellies O- Inferior: superior border of scapula Superior: clavicle I- inferior: clavicle via central tendon Superior: hyoid bone A- depresses the hyoid, Flexion of the head & neck @ the spinal jts N- cervical plexus (ansa cervicalis) A- superior thyroid & transverse cervical)
Sternohyoid
O- sternum (manubrium & medial clavicle) I- hyoid A- depresses the hyoid, Flexion of the head & neck @ the spinal jts N- cervical plexus (ansa cervicalis) A- superior thyroid artery
Sternothyroid
O- sternum (posterior portion of manubrium & clavicle)
I- thyroid
A- depresses the thyroid cartilage, Flexion of the head and neck @ spinal jts
N- cervical plexus (ansa cervicalis)
A- superior thyroid artery
Latissimus Dorsi
“Swimmer’s Muscle”
O- spinous processes of T7-L5, posterior iliac crest & sacrum, lower 4 ribs and sometimes inferior angle of scapula.
I- medial lip of bicipital groove.
A- extension, medial rotation & adduction of the arm @ GH jt. Minor anterior pelvic tilt
N: thoraco-dorsal nerve
A- thoraco-dorsal & posterior intercostal arteries
Rhomboid Major
O- spinous process of T2-T5
I- inferior portion of medial border of scapula between the root of the spine of the scapula and the inferior angle
A- retract & elevates the scapula @ scapulacostal jt.
N: dorsal scapular nerve
A: dorsal scapular artery
Rhomboid Minor
O- spinous process of C7-T1
I- superior portion of medial border of scapula @ root of the spine of the scapula
A: retracts and elevates the scapula @ scapulacostal jt.
N: dorsal scapular nerve
A- dorsal scapular artery
Levator Scapula
O- transverse processes of C1-C4
I- superior angle & superior portion of medial border of scapula
A- elevates the scapula @ scapulacostal jt, extension & lateral Flexion of the neck @ spinal jt.
N- dorsal scapular nerve
A- dorsal scapular artery
Serratus posterior superior
O- spinous process of C7- T3
I- ribs #2-5 (superior borders and external surfaces)
A-elevates ribs #2-5 @ sternocostal and costal spinal jt during breathing.
N: intercostal nerves
A- posterior intercostal arteries
Serratus posterior inferior
O- spinous processes of T11-L2
I- ribs #9-12, inferior borders & external surfaces
A- depresses ribs 9-12 @ sternocostal & costovertebral jt
N- subcostal & intercostal arteries
Iliocostalis
The most lateral of the erector Spinae”
O- (L): medial iliac crest & medial sacral crest (T):ribs #7-12, (C) ribs #3-6
I- (L): ribs #7-12, (T) ribs #1-6 & tvp C7, (C) tvps C4-C6
A- extention, lateral flexion,ipsilateral rotation of neck and trunk @ spinal jts, anteriorly rotates the pelvis.
N- spinal nerves, L,T,C
A- posterior intercostal & lumbar arteries
Longissimus
Intermediate of the erector spinae
O- (T) medial iliac crest, sacrum & transverse processes of L1-L5, (Crv) transverse processes of T1-T5, (Cap) transverse processes of T1-T5 & articular processes of C4-C7
I- (T) transverse process of entire thoracic spine & ribs #3-12, (Crv) transverse processes of C2-C6, (Cap) mastoid process of the occiput
A- extention, lateral flexion, ipsilateral rotation of the head, neck and trunk @ spinal jts, anteriorly rotates the pelvis
N- spinal nerves, C,T,L
A- posterior intercostal & lumbar arteries
Spinalis
The most medial of the erector spinae
O- (T) spinous process of T11-L2, (Crv) inferior nuchal ligament & spinous process of C7
I- (T) spinous process of T4-T8, (Crv) spinous process of C2
Capitus is medial semispinalis Capitus
A- extention and lateral Flexion of the neck & trunk @ spinal jts, anteriorly rotates the pelvis
N- spinal nerves, C,T no L
A- posterior & intercostal lumbar arteries
Semispinalis
Transverso-Spinalis Group
O: T- transverse processes of T6-T10, Cerv- transverse processes of T1-T5, Cap- transverse processes of C7-T6 & articular processes of C4-C6
I: T- spinous processes of C6-T4, Cerv- spinous processes of C2-C5, Cap- between superior & inferior nuchal lines of occiput
A: extention, lateral flexion of head, neck & trunk @ spinal joints. No head rotation.
N: spinal nerves, cervical, thoracic
A: occipital, posterior intercostal & deep cervical arteries
Multifidus
Transverso-Spinalis Group
O: L- mamillory processes of all vertebrae, T- transverse processes of all vertebrae, C- articular process of C4-C7 (runs entire spine from sacrum/ilium & PSIS to C2.
I: spinous processes of vertebrae 2-4 segments above. No head attachment!
A: extention, lateral flexion & contralateral rotation of neck & trunk @ spinal jts. Anterior pelvic rotation.
N: spinal nerves, cervical, thoracic, lumbar
A: occipital, posterior intercostal & lumbar arteries
Rotatores
Transverso-Spinalis Group
O- inferior transverse processes of L5-C2 (runs entire spine C2-L5
I- lamina of vertebrae 1-2 segments above.
A- extention & contralateral rotation of neck & trunk @ spinal jts.
N- spinal nerves, lumbar, thoracic, cervical
A- occipital, posterior intercostal & lumbar arteries
Interspinalis
Found at every level except the thoracic
O: transverse process of lower vertebrae of cervical and lumbar
I: transverse process of higher vertebrae cervical and lumbar.
A: extention of neck and trunk @ spinal jt.
N: spinal nerves
A: posterior intercostal
Levator Costarum
O: transverse process of C7-T11 I: ribs #1-12 @ tubercle. (C7-r1, T1-r2...) A: elevates ribs N: spinal nerves A: posterior intercostal
Quadratus Lumborum
O: posterior iliac crest
I: 12th rib & transverse processes of L1-T4
A: extention & lateral flexion of the trunk @ spinal jts, anteriorly rotates the pelvis, elevates the pelvis at lumbosacral jt
N: lumbar plexus
A: subcostal, lumbar & iliolumbar arteries
Subcostales
O: internal surface of ribs 10-12 I: internal surface of ribs 8-10 A: depresses the ribs 8-10 @ sternocostal & costalspinal jts during forced exhalation. N: intercostal nerves A: posterior intercostal arteries
