Muscles

Question 1

Origin:

• Medial Crest of sacrum (Via broad tendon)
• Lateral Crests of Sacrum
• Dorsal SI and Sacrotuberous Ligament
• Posterior part of Medial Lip of Iliac Crest
• T11-L5 SP’s
• Supraspinous Ligament

Insertion:

• Inferior border of angles of lower 6 or 7 ribs

FD:

Mostly vertical but somewhat lateral

Action:

• Extension of the vertebral column
• Side bending
• Rotation

R:

• Sacrum stuck in a flexed position will affect Iliocostalis lumborum
• Pulls on Sacrotuberous ligament which then pulls on biceps femoris

Answer 1

Iliocostalis Lumborum

Question 2

Longissimus Thoracis

Answer 2

Origin:

• Iliocostalis Lumborum
• TP’s T11-L5
• TLF

Insertion: (2 tendons)

• Thoracic TPs T12-T2
• Lower 9 or 10 Ribs (between tubercles and angles)

Action:

• Extension and SB

Question 2

Semispinalis Capitis

Answer 2

Origin:

• Upper 6 or 7 Thoracic TP’s
• C7 TP
• Cervical Articular Processes C4-6

Insertion:

• Between superior and inferior nuchal lines of occipital bone

R:

Much larger in comparison to semispinalis cervicis If a muscle attaches into the processes it helps with joint position sense 2-3x larger than SCM is CSA (Cross sectional area)

Nerve: Greater occipital artery + nerve

Question 2

Origin:

• C7-T11 TP

Insertion:

• Rib below respective TP

Action:

• rotation of vertebrae
• lateral flexion of vertebrae
• elevates the ribs (aids in respiration)
• Stabilizes the rib

FD:

Inferior and lateral

Nerve:

Innervation is from lateral branches of the dorsal rami of the corresponding thoracic spinal nerves

D:

• 12 pairs -on internal aspect of thoracic cage
• The lower 4 muscle pairs may have an additional attachment to the second rib below their origin

Answer 2

Levator Costarum

Question 3

Rectus Abdominus

Answer 3

Origin:

• Symphysis Pubis
• Pubic Crest

Insertion:

• Anterior Surface of Xiphoid Process
• Anterior Surface of Costal Cartilages 5-7

Action:

• flexes pelvis and vertebral column
• compresses abdomen
• supports viscera

Nerve:

ventral rami of T7-11

Role:

The role of the transverse lines between the abs is to prevent compression of the abdominal organs during flexion

divided by 3 horizontal lines of connective tissue which divide RA and tighten it down to increase mechanical advantage

One large strap muscle would lead to increased force production over a greater range of motion

The sectioned RA limits bulking upon shortening, but also leads to a bead effect, facilitating torso flexion and extension as the visceral contents change volume

Question 4

Levator Costarum

Answer 4

Origin:

• C7-T11 TP

Insertion:

• Rib below respective TP

Action:

• rotation of vertebrae
• lateral flexion of vertebrae
• elevates the ribs (aids in respiration)
• Stabilizes the rib

FD:

Inferior and lateral

Nerve:

Innervation is from lateral branches of the dorsal rami of the corresponding thoracic spinal nerves

D:

• 12 pairs
• on internal aspect of thoracic cage
• The lower 4 muscle pairs may have an additional attachemtn to the second rib below their origin

Question 5

Quadratus Lumborum

Answer 5

Origin:

• Iliolumbar Ligament (Superior/Posterior aspect)
• Posterior aspect Iliac Crest
• TLF

Insertion:

• Lower border of 12th Rib
• L1-4 TP’s

Action:

• depresses 12th rib in respiration
• aids in extension of the trunk
• unilaterally side bends the trunk
• closely related with psoas

Nerve:

dorsal rami of the spinal segment (T12-L3)

R:

• Merges with the diaphram and thus assits in breathing
• if it goes into spasm affecting the thoracic diaphram something else needs to compensate and help us breathe properly

– which is usually are neck muscle (Scalenenes) which increase in tone to lift up the first and second ribs more. Person could come in with TOS but real cause is QL disfunction.

What has a great PSCA QL or glute med? QL

Trendelenburg is both a glute med and QL test

Question 5

Transverse Abdominus

Answer 5

Origin:

• Lower 6 CC (Inner Surface)
• Middle layer of Fascia
• Anterior 2/3 of inner lip of Iliac Crest -

Lateral 1/3 of Inguinal Ligament

Insertion:

• Linea Alba
• Pubic crest
• Pectineal line

Action:

force attenuation

Stabilization

Protection of organs

Nerve:

T7-12, L1 iliohypogastric and ilioinguinal ligament

R:

A weakness of the internal obliques permits a bulging of the anterior abdominal wall, which indirectly tends to increase lordosis. It also helps to stabilize the linea alba, permitting better action by the anterolateral trunk muscles

Question 6

Iliocostalis Lumborum

Answer 6

Origin:

• Medial Crest of sacrum (Via broad tendon)
• Lateral Crests of Sacrum
• Dorsal SI and Sacrotuberous Ligament
• Posterior part of Medial Lip of Iliac Crest
• T11-L5 SP’s
• Supraspinous Ligament

Insertion:

• Inferior border of angles of lower 6 or 7 ribs

FD:

Mostly vertical but somewhat lateral

Action:

• Extension of the vertebral column
• Side bending
• Rotation

R:

• Sacrum stuck in a flexed position will affect Iliocostalis lumborum
• Pulls on Sacrotuberous ligament which then pulls on biceps femoris

Question 7

Origin:

• Lower 6-10 Thoracic TP’s

Insertion:

• Upper 4-8 Thoracic SP’s
• Lower 2 Cervical SP’s

FD:

Vertical, slightly oblique

Action:

Aids in proprioception and segmental stabilization, A little extension, A little side bending, Some rotation

R:

Part of the transversospinalis group Acts as static postural muscles of the vertebral column affects OA joint

Answer 7

Semispinalis Thoracis

Question 7

Origin:

• 3-6 Thoracic SP

Insertion:

• Posterior Tubercles of Upper 2 or 3 Cervical TP’s

Action:

side bends and rotates upper thoracic, cervical and OA joints

Relationship: Deeper

Answer 7

Splenius Cervicis

Question 8

Spinalis Thoracis

Answer 8

Origin:

• T11-L2 SP’s

Insertion:

• Upper 4-8 Transverse SP’s

Question 9

Longissimus Capitus

Answer 9

Origin:

• Upper 4 or 5 Thoracic TPs
• Lower 3 or 4 Cervical Articular Processes

Insertion:

• Mastoid Process

Action:

• Extension, lateral flexion and rotation of the cervical spine; turning the head to face toward the same side
• Extension of the the neck and head, rotation and a little side bending of neck and head

Question 11

Spinalis Capitis

Answer 11

Origin:

• Upper 6 or 7 Thoracic TP’s
• C7 TP
• 4th-6th Cervical Articular Processes

Insertion:

• Area between Superior/Inferior Nuchal Lines

Relationship:

• inseparably connected with semispinalis capitis

Question 12

Splenius Capitis

Answer 12

Origin:

• Lower ½ of Ligamentum Nuchae
• C7 SP - Upper 3 or 4 Thoracic SP

Insertion:

• Mastoid Process
• Occipital Bone inferior to lateral 1/3 of Superior Nuchal Line

FD:

ascend laterally

**Action: **

• extension, lateral flexion and rot’n

Role:

more superficial

Question 13

Spinalis Cervicis

Answer 13

Origin:

• Lower 1/2 Ligamentum Nuchae
• C7 SP

Insertion:

• SP of Axis (C2)
• Occasionally into SP’s of C3 + C4

Relationships:

Extension of supraspinous ligament

50% of your rotation occurs at C2

Question 13

Origin/Insertion:

• Between SP’s
• Cervical = 6 pairs
• Thoracic = 2 or 3 pairs
• Lumbar = 4 pairs

Function/Role:

• aids Erector Spinae in extension

-placed in pairs between spinous processes of continuous vertebrae

Answer 13

Interspinales

Question 14

Obliqus Externus

Answer 14

Origin:

• External Surface Lower 8 Ribs

Insertion:

• Anterior ½ Iliac Crest
• Linea Alba
• Inguinal ligament

Action:

• compresses abdomen
• supports viscera
• forced expiration
• first part of trunk flexion

Nerve:

T7-11

Role:

The upper portion merges with seratus anterior

Lower portion merges with the lats

Question 16

Intertransversarii

Answer 16

Origin/Insertion:

• Between TP’s

Action:

side bends vertebral column

Role:

• small muscles placed between Tp’s of continuous vertebrae in cervical, thoracic and lumbar regions
• 4.5 – 7.3 times the muscles spindles than multifidus
• Length transducers

– position sensors

Question 17

Origin:

• Iliocostalis Lumborum
• TP’s T11-L5
• TLF

Insertion: (2 tendons)

• Thoracic TPs T12 - T2
• Lower 9 or 10 Ribs (between tubercles and angles)

Action:

• Extension and SB

Answer 17

Longissimus Thoracis

Question 18

Transverse Thoracus

Answer 18

Origin:

• Xiphoid Process (Inner Surface)
• Sternum up to Rib 3 (Inner Surface)

Insertion:

• Ribs 2-7 + CC (Inner Surface)

Action:

• aids in expiration and depression of ribs 2-7

Nerve:

Innervation is from the corresponding intercostal nerves

Question 19

Origin:

• External Surface Lower 8 Ribs

Insertion:

• Anterior ½ Iliac Crest
• Linea Alba
• Inguinal ligament

Action:

• compresses abdomen
• supports viscera
• forced expiration
• first part of trunk flexion

Nerve: T7-11

Role: The upper portion merges with seratus anterior Lower portion merges with the lats

Answer 19

Obliqus Externus

Question 20

Origin:

• Upper 6 or 7 Thoracic TP’s
• C7 TP
• 4th-6th Cervical Articular Processes

Insertion:

• Area between Superior/Inferior Nuchal Lines

Relationship:

• inseparably connected with semispinalis capitis

Answer 20

Spinalis Capitis

Question 20

Origin:

• Lower Thoracic or Upper Lumbar TP’s

Insertion:

• Brevis = Lamina of vertebrae above
• Longus = 2 above

Action: Side bend, rot, ext

Stress: Flexion will stretch or lengthen Rotatores

Role: - 4.5 – 7.3 times the muscles spindles than multifidus - Length transducers – position sensors

• Brevis spans one segment
• Longus spans up 2 segments above -11 pairs

Answer 20

Rotatores (Third Layer)

Question 21

**Origin:** - Lower ½ of Ligamentum Nuchae - C7 SP - Upper 3 or 4 Thoracic SP **Insertion:** - Mastoid Process - Occipital Bone inferior to lateral 1/3 of Superior Nuchal Line **FD:** ascend laterally **Action:** - extension, lateral flexion and rot’n **Role:** more superficial

Answer 21

Splenius Capitis

Question 22

**Origin:** - Superior borders of angles of lower 6 ribs **Insertion:** - Superior border of angles of upper 6 ribs - C7 TP **Action:** - extension - side bending

Answer 22

Iliocostalis Thoracis

Question 23

**Origin:** - Upper 6 or 7 Thoracic TP's - C7 TP - Cervical Articular Processes C4-6 **Insertion:** - Between superior and inferior nuchal lines of occipital bone **Role:** Much larger in comparison to semispinalis cervicis If a muscle attaches into the processes it helps with joint position sense 2-3x larger than SCM is CSA (Cross sectional area) **Nerve:** Greater occipital artery + nerve

Answer 23

Semispinalis Capitis

Question 24

Semispinalis Thoracis

Answer 24

**Origin:** - Lower 6-10 Thoracic TP's **Insertion:** - Upper 4-8 Thoracic SP's - Lower 2 Cervical SP's **FD:** Vertical, slightly oblique **Action:** Aids in proprioception and segmental stabilization, A little extension, A little side bending, Some rotation **Role:** Part of the transversospinalis group Acts as static postural muscles of the vertebral column affects OA joint

Question 25

**Origin:** - T11-L2 SP's **Insertion:** - Upper 4-8 Thoracic SP's

Answer 25

Spinalis Thoracis

Question 26

**Origin:** - Superior Border of Ribs + CC **Insertion:** - Rib + CC above **FD:** - is up and medial (perpendicular to Externi) - Up & lateral on the posterior aspect **Action:** - supports intercostal space (maintains space) - lowers rib in forces expiration **D:** 11 pairs **Role:** From the rib angles, they continue as an aponeurotic layer called the internal intercostal membrane and blend with the superior CT ligament

Answer 26

Intercostales Interni

Question 27

**Origin:** - Angles of Ribs 3-6 **Insertion:** - Posterior Tubercles of TP’s C4-6 **Action:** - extension

Answer 27

Iliocostalis Cervicis

Question 28

**Origin:** - Upper 4 or 5 Thoracic TPs - Lower 3 or 4 Cervical Articular Processes **Insertion:** - Mastoid Process **Action:** - Extension, lateral flexion and rotation of the cervical spine; turning the head to face toward the same side - Extension of the the neck and head, rotation and a little side bending of neck and head

Answer 28

Longissimus Capitus

Question 28

**Origin:** - T11, T12, L1, L2 Sp's - lumbar fascia - Also the supraspinous ligament **Insertion:** - inferior border of lower 4 ribs just beyond their angles **FD:** Oblique and lateral **Action:** -aids respiration & lowers ribs **Nerve:** -9th – 11th intercostal nerve **Role:** lies immediately posterior to erector spinae

Answer 28

Serratus Posterior Inferior

Question 29

**Origin:** - Posterior Surface of Sacrum - Medial Surface of PSIS - Dorsal SI Ligament - L5 - C4 TP's **Insertion:** - SP's above (Spans 2 - 4 segments) **Fibre Direction:** - Superior, Oblique and Medial **Function/Role:** Segemental stability (Large amount) **Relationships:** - If a spinal segment is in disfunction, not neccesarily pain, multifidus will start to atrophy within 24 hours -Some of the fibres will merge with the zygoapopheseal joint capsule - so able to give feedback to the body with regard to where the facets are, side bent, rotated etc. - Fibres arent neccesarily merging \*Majority of the fibres will go from segment to segment

Answer 29

Multifidi

Question 30

Interspinales

Answer 30

**Origin/Insertion:** - Between SP's - Cervical = 6 pairs - Thoracic = 2 or 3 pairs - Lumbar = 4 pairs **Function/Role:** - aids Erector Spinae in extension **Relationship:** placed in pairs between spinous processes of continuous vertebrae

Question 31

**Origin:** - Sp’s of C7, T1, T2, T3 - lower part of ligamentum nuchae - Supraspinous ligament **Insertion:** - upper border of ribs 2-5 - Inserts just lateral to the rib angles on their superior and superfical surfaces **Action:** -aids in respiration & elevates ribs **Nerve:** - 2nd – 4th intercostal nerves

Answer 31

Serratus Posterior Superior

Question 33

Intercostales Externi

Answer 33

**Origin:** - Inferior border of Rib below Tubercle **Insertion:** - Superior border of Rib below **FD:** is down & medial (Ant), down & lat (Post) **Action:** - supports intercostal space (protective) - elevates rib in inspiration **D:** 11 pairs **R: ** Orginates from the tubercles of the rib, blending with the posterior fibres of the CT ligaments

Question 36

Iliocostalis Cervicis

Answer 36

**Origin:** - Angles of Ribs 3-6 **Insertion:** - Posterior Tubercles of TP’s C4-6 **Action:** - extension

Question 38

Iliocostalis Thoracis

Answer 38

**Origin:** - Superior borders of angles of lower 6 ribs **Insertion:** - Superior border of angles of upper 6 ribs - C7 TP **Action:** - extension - side bending

Question 39

**Origin:** - Xiphoid Process (Inner Surface) - Lower 6 Ribs + CC (Inner Surface) - Anterior Surface L1-L3 - Right/Left Crura - Anterior Longitudinal Ligament - IVD - Medial / Lateral Arcuate Ligaments **Insertion:** - Central Tendon **FD:** The medial tendinous margins of the crura pass anteriorly and medialward, and meet in the middle line to form an arch across the front of the aorta known as the median arcuate ligament; this arch is often poorly defined. The area behind this arch is known as the aortic hiatus. **N:** -innervated by phrenic nerve C3, C4, C5 **R:** At their origins the crura are tendinous in structure, and blend with the anterior longitudinal ligament of the vertebral column. The right crus, larger and longer than the left, arises from the anterior surfaces of the bodies and intervertebral fibrocartilages of the upper three lumbar vertebrae. The left crus arises from the corresponding parts of the upper two lumbar vertebrae only. The medial fibers of the right crus ascend on the left side of the esophageal hiatus, and occasionally a fasciculus of the left crus crosses the aorta and runs obliquely through the fibers of the right crus toward the vena caval foramen. pericardial sac attaches to the diaphragm made up of 3 parts right, which is the largest and corresponds to right lung anterior, corresponding to heart left, which is the smallest and correspond to left lung **Holes of the Diaphragm:** -vena cava -esophageal hiatus (formed by right crus) -aortic hiatus (formed where right and left crura meet superiorly)…aorta sits posterior to diaphragm and anterior to the vertebral column -phrenic nerve

Answer 39

Thoracic Diaphragm

Question 40

**Origin:** - Upper 5 or 6 Thoracic TP's **Insertion:** - C2-C5 SP's

Answer 40

Semispinalis Cervicis

Question 41

**Origin:** - Upper 4 or 5 Thoracic TPs **Insertion:** - Posterior Tubercles of TP's C2-6 **Action:** - Extension and SB

Answer 41

Longissimus Cervicis

Question 42

**Origin:** - Symphysis Pubis - Pubic Crest **Insertion:** - Anterior Surface of Xiphoid Process - Anterior Surface of Costal Cartilages 5-7 **Action:** - flexes pelvis and vertebral column - compresses abdomen - supports viscera **Nerve:** ventral rami of T7-11 **Role:** The role of the transverse lines between the abs is to prevent compression of the abdominal organs during flexion divided by 3 horizontal lines of connective tissue which divide RA and tighten it down to increase mechanical advantage One large strap muscle would lead to increased force production over a greater range of motion The sectioned RA limits bulking upon shortening, but also leads to a bead effect, facilitating torso flexion and extension as the visceral contents change volume

Answer 42

Rectus Abdominus

Question 43

**Origin:** - TLF - Anterior 2/3 of Iliac Crest (middle lip) - Lateral 2/3 of Inguinal Ligament **Insertion:** Lower 3 CC Linea Alba Pubic Crest Pectineal Line **Action:** Force closure of symphasis pubis compresses abdomen aids in expiration supports viscera flex the vertebral column **Nerve:** T9-12, L1 Iliohypogastric and ilioinguinal nerve **Role:** The more inferiorly placed portion of the muscle exerts a pull on the pelvis, a motion that is medially directed, effectively increasing compression of the pubic symphysis. This muscle can exert a powerful forward and elevation movement of the pelvis, a motion that is essential in sprinting

Answer 43

Obliqus Internus

Question 45

Obliqus Internus

Answer 45

**Origin:** - TLF - Anterior 2/3 of Iliac Crest (middle lip) - Lateral 2/3 of Inguinal Ligament **Insertion:** Lower 3 CC Linea Alba Pubic Crest Pectineal Line **Action:** Force closure of symphasis pubis compresses abdomen aids in expiration supports viscera flex the vertebral column **Nerve:** T9-12, L1 Iliohypogastric and ilioinguinal nerve **R:** The more inferiorly placed portion of the muscle exerts a pull on the pelvis, a motion that is medially directed, effectively increasing compression of the pubic symphysis. This muscle can exert a powerful forward and elevation movement of the pelvis, a motion that is essential in sprinting

Question 46

Longissimus Cervicis

Answer 46

**Origin:** - Upper 4 or 5 Thoracic TPs **Insertion:** - Posterior Tubercles of TP's C2-6 **Action:** - Extension and SB

Question 47

**Origin:** - Xiphoid Process (Inner Surface) - Sternum up to Rib 3 (Inner Surface) **Insertion:** - Ribs 2-7 + CC (Inner Surface) **Action:** - aids in expiration and depression of ribs 2-7 **N:** -Innervation is from the corresponding intercostal nerves

Answer 47

Transverse Thoracus

Question 48

**Origin:** - Lower 1/2 Ligamentum Nuchae - C7 SP **Insertion:** - SP of Axis (C2) - Occasionally into SP's of C3 + C4 **R:** Extension of supraspinous ligament 50% of your rotation occurs at C2

Answer 48

Spinalis Cervicis

Question 49

Splenius Cervicis

Answer 49

**Origin:** - 3-6 Thoracic SP **Insertion:** - Posterior Tubercles of Upper 2 or 3 Cervical TP's **A:** side bends and rotates upper thoracic, cervical and OA joints **R:** Deeper than Splenius Capitus

Question 50

Semispinalis Cervicis

Answer 50

**Origin:** - Upper 5 or 6 Thoracic TP's **Insertion:** - C2-C5 SP's

Question 50

Multifidi

Answer 50

**Origin:** - Posterior Surface of Sacrum - Medial Surface of PSIS - Dorsal SI Ligament - L5 - C4 TP's **Insertion:** - SP's above (Spans 2 - 4 segments) **Fibre Direction:** - Superior, Oblique and Medial **Function/Role:** Segemental stability (Large amount) **Relationships:** - If a spinal segment is in disfunction, not neccesarily pain, multifidus will start to atrophy within 24 hours - Some of the fibres will merge with the zygoapopheseal joint capsule - so able to give feedback to the body with regard to where the facets are, side bent, rotated etc. - Fibres arent neccesarily merging \*Majority of the fibres will go from segment to segment

Question 51

**Origin:** - Inferior border of Rib below Tubercle **Insertion:** - Superior border of Rib below **FD:** is down & medial (Ant), down & lat (Post) **Action:** - supports intercostal space (protective) - elevates rib in inspiration **D:** 11 pairs **R:** Orginates from the tubercles of the rib, blending with the posterior fibres of the CT ligaments

Answer 51

Intercostales Externi

Question 53

**Origin:** - Lower 6 CC (Inner Surface) - Middle layer of Fascia - Anterior 2/3 of inner lip of Iliac Crest - Lateral 1/3 of Inguinal Ligament **Insertion:** - Linea Alba - Pubic crest - Pectineal line **A:** force attenuation Stabilization Protection of organs **Nerve:** T7-12, L1 iliohypogastric and ilioinguinal ligament **Role:** A weakness of the internal obliques permits a bulging of the anterior abdominal wall, which indirectly tends to increase lordosis. It also helps to stabilize the linea alba, permitting better action by the anterolateral trunk muscles

Answer 53

Transverse Abdominus

Question 54

Rotatores

Answer 54

**Origin:** - Lower Thoracic or Upper Lumbar TP's **Insertion:** - Lamina of vertebrae above (Brevis) - Longus = 2 above **A:** Side bend, rot, ext **S:** Flexion will stretch or lengthen Rotatores **R:** - 4.5 – 7.3 times the muscles spindles than multifidus - Length transducers – position sensors - Brevis spans one segment - Longus spans up 2 segments above - 11 pairs

Question 55

**Origin:** - Iliolumbar Ligament (Superior/Posterior aspect) - Posterior aspect Iliac Crest - TLF **Insertion:** - Lower border of 12th Rib - L1-4 TP's **Action:** - depresses 12th rib in respiration - aids in extension of the trunk - unilaterally side bends the trunk - closely related with psoas **Nerve:** dorsal rami of the spinal segment (T12-L3) **Role:** Merges with the diaphram and thus assits in breathing - if it goes into spaasm affecting the thoracic diaphram something else needs to compensate and help us breathe properly – which is usually are neck muscle (Scalenenes) which increase in tone to lift up the first and second ribs more. Person could come in with TOS but real cause is QL disfunction. What has a great PSCA QL or glute med? QL Trendelenburg is both a glute med and QL test

Answer 55

Quadratus Lumborum

Question 56

Intercostales Interni

Answer 56

**Origin:** - Superior Border of Ribs + CC **Insertion:** - Rib + CC above **FD:** -is up and medial (perpendicular to Externi) (Posterior aspect) **Action:** - supports intercostal space (maintains space) - lowers rib in forces expiration **D:** 11 pairs **R:** From the rib angles, they continue as an aponeurotic layer called the internal intercostal membrane and blend with the superior CT ligament

Question 57

Serratus Posterior Inferior

Answer 57

**Origin:** - T11, T12, L1, L2 Sp's - TLF - Supraspinous ligament **Insertion:** - Inferior border lower 4 ribs (just beyond their angles) **FD:** Oblique and lateral **Action:** -aids respiration & lowers ribs **Nerve:** -9th–11th intercostal nerve **R:** lies immediately posterior to erector spinae

Question 58

Thoracic Diaphragm

Answer 58

**Origin:** - Xiphoid Process (Inner Surface) - Lower 6 Ribs + CC (Inner Surface) - Anterior Surface L1-L3 - Right/Left Crura - Anterior Longitudinal Ligament - Medial / Lateral Arcuate Ligaments **Insertion:** - Central Tendon **FD:** The medial tendinous margins of the crura pass anteriorly and medialward, and meet in the middle line to form an arch across the front of the aorta known as the median arcuate ligament; this arch is often poorly defined. The area behind this arch is known as the aortic hiatus. **N:** innervated by phrenic nerve C3, C4, C5 **R:** At their origins the crura are tendinous in structure, and blend with the anterior longitudinal ligament of the vertebral column. The right crus, larger and longer than the left, arises from the anterior surfaces of the bodies and intervertebral fibrocartilages of the upper three lumbar vertebrae. The left crus arises from the corresponding parts of the upper two lumbar vertebrae only. The medial fibers of the right crus ascend on the left side of the esophageal hiatus, and occasionally a fasciculus of the left crus crosses the aorta and runs obliquely through the fibers of the right crus toward the vena caval foramen. pericardial sac attaches to the diaphragm made up of 3 parts right, which is the largest and corresponds to right lung anterior, corresponding to heart left, which is the smallest and correspond to left lung Holes of the Diaphragm: - vena cava - esophageal hiatus (formed by right crus) - aortic hiatus (formed where right and left crura meet superiorly)…aorta sits posterior to diaphragm and anterior to the vertebral column -phrenic nerve

Question 59

**Origin/Insertion:** - Between TP's **Action:** side bends vertebral column **Role:** - small muscles placed between Tp’s of continuous vertebrae in cervical, thoracic and lumbar regions - 4.5 – 7.3 times the muscles spindles than multifidus - Length transducers – position sensors

Answer 59

Intertransversarii

Question 60

Serratus Posterior Superior

Answer 60

**Origin:** - C7-T3 SP - Lower 1/2 Ligamentum Nuchae - Supraspinous ligament **Insertion:** - upper border of ribs 2-5 - Inserts just lateral to the rib angles on their superior and superfical surfaces **Action:** -aids in respiration & elevates ribs **Nerve:** - 2nd–4th intercostal nerves