The Spine (1+2) Flashcards
What is a lamina?
A lamina is the part of the neural arch that is between the spinous and transverse processes.
What is a pedicle?
A pedicle is the part of the neural arch that is between the transverse process and the body.
Describe the normal adult curvature of the spine.
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).
What is curvature of the spine in the coronal plane called?
Scoliosis
List 3 unique features of a typical cervical vertebra and state their functions.
(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.
List 3 unique features of a typical thoracic vertebra.
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.
List 3 unique features of a typical lumbar vertebrae.
No transverse foramina or costal facets. Superior articular facets face posteromedially. Has a hatchet shaped spine.
Which cervical vertebrae are considered atypical?
C1,2 and 7
Why is C1 atypical?
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.
Why is C2 atypical?
C2 (axis) features the odontoid process (dens), it is a superior protrusion.
Why is C7 atypical?
C7 (vertebra prominens) features a long, non-bifid spinous process. Enlarged transverse foramina.
Which thoracic vertebrae are considered atypical?
T1,10,11,12. (sometimes T9)
Why is T1 atypical?
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.
Why are T10,11,12 atypical?
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.
State the boundaries of the intervertebral foramen.
Superior-inferior vertebral notch
Inferior-superior vertebral notch
Anterior-posterolateral margins of the vertebral bodies and the intervertebral disc
Posterior-facet joint
Label the CS of this typical C vertebra.
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
Label this typical T vertebra.
A=spinous process
B=lamina
C=pedicle
D=body
E=vertebral foramen
F=transverse process
G=superior articular facet
H=neural arch
Where does the greater occipital nerve originate?
From the dorsal rami of C2
What makes the spinous process of T3 palpable?
It is in line with the spine of the scapula.
What makes the spinous process of T12 palpable?
It articulates with the lowest floating rib, this is also palpable.
What makes the spinous process of L4 palpable?
It is in line with the iliac crest.
At what level is a lumbar puncture carried out and for what cause?
L3,4,5 to draw out spinal fluid, which is used for analysis or releasing intercranial pressure.
How many back muscles are there? Classify them.
- Superior, intermediate and deep (superficial, intermediate, deep, deep minor)
What are the superficial (extrinsic) back muscles?
Trapezius, latissimus dorsi, rhomboid major/minor and levator scapulae.
What are the intermediate (extrinsic) back muscles?
serratus posterior superior/inferior
What are the deep (intrinsic) back muscles?
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
State the classification, origins, insertions, actions and nerve supply of serratus posterior superior.
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.
State the classification, origins, insertions, actions and nerve supply of serratus posterior inferior.
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
Label the muscles shown.
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
State the classification, origins, insertions, actions and nerve supply of splenius capitis.
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)
State the classification, origins, insertions, actions and nerve supply of splenius cervicis.
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)
State the classification, origins, insertions, actions and nerve supply of rotatores.
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
State the classification, origins, insertions, actions and nerve supply of multifidus.
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
State the classification, origins, insertions, actions and nerve supply of semispinalis.
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
Where does the ligamentum flavum attach?
The ligamentum flavum attaches to the posterior surface of the lamina below and the anterior surface of the lamina above.
What is spondylosis?
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.
Which deep transversospinal group muscle is most well-developed in the thoracic region?
Multifidus
What is the root value of the nerve supplying the skin on the back of the head, inferior to the vertex?
Greater occipital nerve (C2)
Which erector spinae group muscles have a herringbone appearance?
Iliocostalis
What posterior abdominal wall muscle is both a trunk and hip flexor?
Iliopsoas
State the boundaries of the sub-occipital triangle.
Superior: inferior rectus capitis posterior major
Lateral: obliquus capitis superior
Medial: obliquus capitis inferior
State the contents of the sub-occipital triangle from lateral to medial.
Suboccipital nerve (C1), vertebral artery, posterior arch of atlas (C1)
Which ligament prevents hyperextension of the vertebral column?
The anterior longitudinal ligament
What is the cauda equina?
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.
