The Spine (1+2)

Question 1

What is a lamina?

Answer 1

A lamina is the part of the neural arch that is between the spinous and transverse processes.

Question 2

What is a pedicle?

Answer 2

A pedicle is the part of the neural arch that is between the transverse process and the body.

Question 3

Describe the normal adult curvature of the spine.

Answer 3

Cervical lordosis (concave curvature of the neck). Thoracic kyphosis (convex curvature of the upper back). Lumbar lordosis (concave curvature of lower back). Sacral kyphosis (convex curvature of spinal base).

Question 4

What is curvature of the spine in the coronal plane called?

Answer 4

Scoliosis

Question 5

List 3 unique features of a typical cervical vertebra and state their functions.

Answer 5

(C3-C6) Transverse foramina allow passage of vertebral arteries and veins. Bifid spinous process has a forked appearance allowing for attachment of muscles and ligaments (especially the nuchal ligament). Their superior articular processes are posterolaterally angled while the inferior articular processes are anteromedially angled, but these facets have a relatively gentle incline.

Question 6

List 3 unique features of a typical thoracic vertebra.

Answer 6

Costal facets (demifacets) articulate with the heads and tubercles of ribs. Long, inferiorly angled spinous processes. Their superior articular processes are posterolaterally angled while the inferior articular processes are anteromedially angled, but these facets have a relatively sharp incline.

Question 7

List 3 unique features of a typical lumbar vertebrae.

Answer 7

No transverse foramina or costal facets. Superior articular facets face posteromedially. Has a hatchet shaped spine.

Question 8

Which cervical vertebrae are considered atypical?

Answer 8

C1,2 and 7

Question 9

Why is C1 atypical?

Answer 9

C1 (atlas) has no vertebral body or spinous process. The concave shape of the superior articular facet suits the occipital bone to form the atlanto-occipital joint. It allows for cervical flexion, extension and rotation.

Question 10

Why is C2 atypical?

Answer 10

C2 (axis) features the odontoid process (dens), it is a superior protrusion.

Question 11

Why is C7 atypical?

Answer 11

C7 (vertebra prominens) features a long, non-bifid spinous process. Enlarged transverse foramina.

Question 12

Which thoracic vertebrae are considered atypical?

Answer 12

T1,10,11,12. (sometimes T9)

Question 13

Why is T1 atypical?

Answer 13

T1 has a full costal facet on its superior aspect for the 1st rib and demifacets on its lateral aspect for the 2nd rib. Resembles a cervical vertebra.

Question 14

Why are T10,11,12 atypical?

Answer 14

Facet orientations are more similar to L vertebrae, making it more mobile. T10 only has one complete costal facet instead of the regular 2 demifacets. T11,12 has a single costal facet for articulation with the head of the rib. T11,12 have floating ribs and do not attach to sternum nor cartilage so they don’t have facets on their transverse processes.

Question 15

State the boundaries of the intervertebral foramen.

Answer 15

Superior-inferior vertebral notch
Inferior-superior vertebral notch
Anterior-posterolateral margins of the vertebral bodies and the intervertebral disc
Posterior-facet joint

Question 16

Label the CS of this typical C vertebra.

Answer 16

A=pia mater
B=arachnoid
C=dura mater (spinal dural sheath)
D=spinal meninges
E=bone of vertebra
F=dorsal root ganglion
G=body of vertebra
H=subarachnoid space
I=subdural space
J=epidural space

Question 17

Label this typical T vertebra.

Answer 17

A=spinous process
B=lamina
C=pedicle
D=body
E=vertebral foramen
F=transverse process
G=superior articular facet
H=neural arch

Question 18

Where does the greater occipital nerve originate?

Answer 18

From the dorsal rami of C2

Question 19

What makes the spinous process of T3 palpable?

Answer 19

It is in line with the spine of the scapula.

Question 20

What makes the spinous process of T12 palpable?

Answer 20

It articulates with the lowest floating rib, this is also palpable.

Question 21

What makes the spinous process of L4 palpable?

Answer 21

It is in line with the iliac crest.

Question 22

At what level is a lumbar puncture carried out and for what cause?

Answer 22

L3,4,5 to draw out spinal fluid, which is used for analysis or releasing intercranial pressure.

Question 23

How many back muscles are there? Classify them.

Answer 23

24. Superior, intermediate and deep (superficial, intermediate, deep, deep minor)

Question 24

What are the superficial (extrinsic) back muscles?

Answer 24

Trapezius, latissimus dorsi, rhomboid major/minor and levator scapulae.

Question 25

What are the intermediate (extrinsic) back muscles?

Answer 25

serratus posterior superior/inferior

Question 26

What are the deep (intrinsic) back muscles?

Answer 26

Deep superficial: splenius capitis/cervicis Deep intermediate (erector spinae): iliocostalis (lumborum, thoracis, servicis, it is most lateral), longissimus (intermediate), spinalis (both thoracis, servicis, capitis, it is most medial) Deep deep (transversospinal): semispinalis (thoracis, servicis, capitis), multifidus, rotatores (longus, brevis). Deep minor: interspinales, intertransversarii, levatores costarum

Question 27

State the classification, origins, insertions, actions and nerve supply of serratus posterior superior.

Answer 27

Classification: intermediate back Origins: spinous processes of C7 to T3, nuchal ligament Insertions: upper border of 2nd to 5th ribs Actions: Elevation of ribs (for inhalation) Nerve supply: intercostal nerves (ventral rami) of T2-5.

Question 28

State the classification, origins, insertions, actions and nerve supply of serratus posterior inferior.

Answer 28

Classification: intermediate back Origins: spinous processes of T11 to L2 Insertions: inferior borders of 9th to 12th ribs Actions: depression of ribs (for exhalation) Nerve supply: intercostal nerves (ventral rami) of T9-12

Question 29

Label the muscles shown.

Answer 29

1=rotatores 2=multifidus 3=semispinalis 4=longissimus 5=iliocostalis 6=posterior layer of thoracolumbar fascia 7=serratus posterior 8=latissimus dorsi 9=trapezius 10=spinalis

Question 30

State the classification, origins, insertions, actions and nerve supply of splenius capitis.

Answer 30

Classification: deep superficial back Origins: nuchal ligament, spinous processes of C7 to T3 Insertions: mastoid process, lateral 3rd of superior nuchal line (occipital bone) Actions: unilateral (head rotation, lateral flexion) and bilateral contraction (head and neck extension) Nerve supply: dorsal rami of C spinal nerves (C3,4)

Question 31

State the classification, origins, insertions, actions and nerve supply of splenius cervicis.

Answer 31

Classification: deep superficial back Origins: spinous process of T3-6 Insertions: transverse process of C1-3 Actions: unilateral (head rotation, lateral flexion) and bilateral contraction (head and neck extension) Nerve supply: dorsal rami of C spinal nerves (C5-8)

Question 32

State the classification, origins, insertions, actions and nerve supply of rotatores.

Answer 32

Classification: deep deep back muscles Origins: transverse processes of T1 to L5 Insertions: spinous process of vertebra directly above (brevis) or 2 above (longus) Actions: unilateral contraction: contralateral rotation of vertebrae. Bilateral contraction: spinal extension and stabilization. Nerve supply: dorsal rami of spinal nerves in respective regions

Question 33

State the classification, origins, insertions, actions and nerve supply of multifidus.

Answer 33

Classification: deep deep back muscles Origins: posterior sacrum, iliac crest, mammillary processes of L vertebrae, transverse processes of T vertebrae, articular processes of C4-7 Insertions: spinous processes of vertebrae that are 2 to 4 above the origin or along the length of the vertebral column Actions: unilateral contraction: contralateral rotation. Bilateral contraction: spinal extension and stabilization. Nerve supply: dorsal rami of spinal nerves

Question 34

State the classification, origins, insertions, actions and nerve supply of semispinalis.

Answer 34

Classification: deep deep back muscles Origins: TRANSVERSE PROCESSES OF C4-T7 (capitis), T1-6 (cervicis), T6-12 (thoracis) Insertions: superior and inferior nuchal lines of the occipital bone (capitis), spinous processes of C2-5 (cervicis), spinous processes of C6 to T4 (thoracis) Actions: contralateral rotation. Bilateral rotation: extension of head and neck (capitis), extension of C and T spine (cervicis and thoracis), stabilization and posture. Nerve supply: dorsal rami of spinal nerves

Question 35

Where does the ligamentum flavum attach?

Answer 35

The ligamentum flavum attaches to the posterior surface of the lamina below and the anterior surface of the lamina above.

Question 36

What is spondylosis?

Answer 36

Spondylosis involves a defect in the pars interarticularis, the part of the vertebra between the superior and inferior articular processes. It typically occurs at L5.

Question 37

Which deep transversospinal group muscle is most well-developed in the thoracic region?

Answer 37

Multifidus

Question 38

What is the root value of the nerve supplying the skin on the back of the head, inferior to the vertex?

Answer 38

Greater occipital nerve (C2)

Question 39

Which erector spinae group muscles have a herringbone appearance?

Answer 39

Iliocostalis

Question 40

What posterior abdominal wall muscle is both a trunk and hip flexor?

Answer 40

Iliopsoas

Question 41

State the boundaries of the sub-occipital triangle.

Answer 41

Superior: inferior rectus capitis posterior major Lateral: obliquus capitis superior Medial: obliquus capitis inferior

Question 42

State the contents of the sub-occipital triangle from lateral to medial.

Answer 42

Suboccipital nerve (C1), vertebral artery, posterior arch of atlas (C1)

Question 43

Which ligament prevents hyperextension of the vertebral column?

Answer 43

The anterior longitudinal ligament

Question 44

What is the cauda equina?

Answer 44

The cauda equina is a bundle of spinal nerves and nerve roots at the level of L1/2. Cauda equina syndrome is symptomized by severe lower bac pain, incontinence and weakness of lower limbs.