Axial Skeletal Muscles

Question 0

Pectorals Major

Answer 0

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)

Question 1

Trapezius

Answer 1

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

Question 2

Pectoralis Minor

Answer 2

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)

Question 3

Serratus Anterior

Answer 3

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)

Question 4

Subclavius

Answer 4

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

Question 5

External Intercostals

Answer 5

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

Question 6

Internal Intercostals

Answer 6

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.

Question 7

Innermost Intercostals

Answer 7

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

Question 8

Transversus Thoracis

Sternocostalis

Answer 8

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

Question 9

External Obliques

Answer 9

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

Question 10

Internal Obliques

Answer 10

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

Question 11

Rectus Abdominus

Answer 11

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

Question 12

Transverse Abdominus 
(Corsette or cumberbun muscle)

Answer 12

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

Question 13

Pyramidalis

20% of people do not have this muscle

Answer 13

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

Question 14

Diaphragm

Answer 14

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

Question 15

Psoas Major

Answer 15

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

Question 16

Psoas minor

Missing in 40% of people

Answer 16

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

Question 17

Iliacus

Answer 17

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.

Question 18

Splenius Capitis

Answer 18

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

Question 19

Splenius Cervicis

Answer 19

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

Question 20

Suboccipitals - Rectus Capitis Posterior Minor

Answer 20

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)

Question 21

Suboccipitals- Rectus Capitis Posterior Major

Answer 21

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)

Question 22

Suboccipitals- Obliquus Capitus Inferior

Answer 22

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)

Question 23

Suboccipitals- Obliquus Capitus Superior

Answer 23

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)

Question 24

Platysma

Answer 24

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

Question 25

Sternocleidomastoid

Answer 25

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.

Question 26

Anterior Scalenes

Answer 26

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

Question 27

Middle Scalenes

Answer 27

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)

Question 28

Posterior Scalenes

Answer 28

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)

Question 29

Rectus Capitis anterior

Answer 29

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

Question 30

Rectus Capitis lateralis

Answer 30

``` 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 ```

Question 31

Longus colli (prevertebral)

Answer 31

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

Question 32

Longus Capitus (prevertebral)

Answer 32

``` 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 ```

Question 33

Mylohyoid

Answer 33

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

Question 34

Geniohyoid - deep to mylohyoid

Answer 34

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

Question 35

Digastric

Answer 35

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

Question 36

Stylohyoid

Answer 36

``` O- Styloid process of the temporal bone I- hyoid A- elevates the hyoid N- facial nerve (CN7) A- occipital, posterior auricular & facial arteries ```

Question 37

Thyrohyoid

Answer 37

``` O- thyroid cartilage I- hyoid A- depresses the hyoid, Flexion of the head & neck @ spinal jts N- hypoglossal nerve (CN12) A- superior thyroid artery ```

Question 38

Omohyoid

Answer 38

``` 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) ```

Question 39

Sternohyoid

Answer 39

``` 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 ```

Question 40

Sternothyroid

Answer 40

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

Question 41

Latissimus Dorsi | "Swimmer's Muscle"

Answer 41

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

Question 42

Rhomboid Major

Answer 42

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

Question 43

Rhomboid Minor

Answer 43

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

Question 44

Levator Scapula

Answer 44

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

Question 45

Serratus posterior superior

Answer 45

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

Question 46

Serratus posterior inferior

Answer 46

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

Question 47

Iliocostalis The most lateral of the erector Spinae"

Answer 47

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

Question 48

Longissimus Intermediate of the erector spinae

Answer 48

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

Question 49

Spinalis The most medial of the erector spinae

Answer 49

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

Question 50

Semispinalis Transverso-Spinalis Group

Answer 50

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

Question 51

Multifidus Transverso-Spinalis Group

Answer 51

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

Question 52

Rotatores Transverso-Spinalis Group

Answer 52

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

Question 53

Interspinalis | Found at every level except the thoracic

Answer 53

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

Question 54

Levator Costarum

Answer 54

``` O: transverse process of C7-T11 I: ribs #1-12 @ tubercle. (C7-r1, T1-r2...) A: elevates ribs N: spinal nerves A: posterior intercostal ```

Question 55

Quadratus Lumborum

Answer 55

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

Question 56

Subcostales

Answer 56

``` 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 ```