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Question 1

Describe the vertebral column

Answer 1

-Part of the axial skeleton (which also includes the skull, ribs, and sternum)
-Consists of vertebrae and intervertebral (IV) discs
-Total of 33 vertebrae (24 mobile; 9 fused)
o 7 cervical vertebrae
o 12 thoracic vertebrae (associated with ribs)
o 5 lumbar vertebrae
o 5 sacral vertebrae (fused to form sacrum)
o 4 coccygeal vertebrae (fused to form coccyx)

Question 2

What is the Functions of the vertebral column?

Answer 2

-protect spinal cord and spinal nerves
-posture and locomotion
• supports and transmits weight of body
• provides a relatively flexible axis for torso and head
• movements include: extension/flexion, lateral flexion, rotation

Question 3

What are the curvatures of the vertebral column?

Answer 3

1) Primary curvatures or kyphoses (thoracic and sacral)
2) Secondary curvatures or lordoses (cervical and lumbar)
3) Abnormal curvatures

Question 4

Describe the Primary curvatures

Answer 4

Concave anteriorly and develop early in ontogeny, during the fetal period (when the entire vertebral column is concave anteriorly)

Question 5

Describe the Secondary curvatures

Answer 5

-Concave posteriorly and develop during infancy

1) Cervical curvature develops in response to infant learning to hold head upright
2) Lumbar curvature develops in response to infant learning to sit upright and walk

Question 6

Describe the Abnormal curvatures

Answer 6

1) Excessive Thoracic Kyphosis is an exaggerated thoracic curvature; “humpback” deformity
2) Excessive Lumbar Lordosis is an exaggerated lumbar curvature; “swayback” deformity
3) Scoliosis is a lateral deviation coupled with a rotational component

Question 7

Describe the Features of the vertebrae

Answer 7

1) vertebral body
2) vertebral (neural) arch
3) spinous process
4) transverse processes
5) articular processes
6) vertebral foramen
7) vertebral canal
8) vertebral notches
9) intervertebral foramen

Question 8

Describe the vertebral body

Answer 8

• located anteriorly
• articulates with intervertebral discs
• supports body weight (thus, gradually increase in size from the cervical region to the superior sacral region; the weight is then transferred through the SI joints to the pelvis and lower extremities, so the vertebral bodies gradually decrease in size from the mid sacral to the coccygeal region)

Question 9

Describe the vertebral (neural) arch

Answer 9

• located posterior to the vertebral body
• 2 pedicles (attached to vertebral body)
• 2 laminae (attached to pedicles)

Question 10

Describe the spinous process

Answer 10

-posterior projection that forms where the laminae fuse

Question 11

Describe the transverse processes

Answer 11

-lateral projections at the junction of pedicle and lamina

Question 12

Describe the articular processes

Answer 12

• superior and inferior projections at the junction of pedicle and lamina
• 2 superior and 2 inferior articular processes per vertebra
• superior processes articulate with inferior processes of the vertebra above
• inferior processes articulate with superior processes of the vertebra below
• smooth articular surface = facet (which form facet joints or zygapophysial joints)

Question 13

Describe the vertebral foramen

Answer 13

-formed by the vertebral arch and the posterior surface of the vertebral body

Question 14

Describe the vertebral canal

Answer 14

• bony canal formed by adjacent vertebral foramina

- contains the spinal cord and associated structures

Question 15

Describe the vertebral notches

Answer 15

• 2 superior and 2 inferior vertebral notches per vertebra
• located on the superior, or inferior, aspect of the pedicles
• adjacent superior and inferior notches help form an intervertebral foramen

Question 16

Describe the intervertebral foramen

Answer 16

-blood vessels and nerves traverse this foramen

Question 17

What are the Regional differences of the Cervical vertebrae (n=7)?

Answer 17

• small vertebral bodies
• posteriorly projecting spinous processes
• vertebra C7 is called vertebra prominens because it has the most prominent cervical spinous process
• transverse foramina (holes in the transverse processes for the passage of the vertebral arteries and veins)
• uncinate processes (elevated superolateral margin of body)

-atlas (C1)
◊ lacks a vertebral body and spinous process; ring-shaped (with posterior & anterior vertebral arches)
◊ superior articular facets for articulation with the occipital condyles of the cranium
◊ inferior articular facets for articulation with the superior articular facets of the axis (C2)

-axis (C2)
◊ dens process is the portion of the C1 vertebral body that is incorporated into the C2 vertebra during development
◊ large superior articular facets for articulation with the inferior articular facets of the atlas (C1)

Question 18

What are the Regional differences of the Thoracic vertebrae (n=12)

Answer 18

• spinous processes are long and slender and slant inferiorly to the level of vertebral body below
• costal facets on vertebral bodies and transverse processes, for articulation with ribs

Question 19

What are the Regional differences of the Lumbar vertebrae (n=5)

Answer 19

• large vertebral bodies
• robust spinous processes
• the posteriorly projecting spinous processes facilitate the ability to perform a lumbar puncture (spinal tap), as there are gaps between adjacent lumbar spinous processes, especially when the vertebral column is flexed

Question 20

What is the Lumbosacral angle?

Answer 20

marks the junction of the L5 vertebra and sacrum

Question 21

What are the Regional differences of the Sacrum

Answer 21

• 5 sacral vertebrae fuse into one triangular-shaped bone
• vertebral canal continues as sacral canal, which ends at the sacral hiatus (bounded by sacral cornua)
• 4 pairs of anterior and 4 pairs of posterior sacral foramina (for the transmission of ventral and dorsal rami of sacral spinal nerves)
• The fused spinous process of the sacral vertebrae form the median crest
• The sacral hiatus is an opening that can be used for administering epidural anesthesia

Question 22

What are the Regional differences of the Coccyx

Answer 22

• 4 coccygeal vertebrae fuse into one triangular-shaped bone

- focal point for muscle (e.g., coccygeus) and ligament (e.g., sacrospinous ligament) attachment

Question 23

What are some General Comments of Intervertebral (IV) Discs?

Answer 23

• Functions: distribute force and weight; provide flexibility to vertebral column (especially in cervical and lumbar regions)
• IV discs are named according to the two vertebrae with which they articulate (for example, the IV disc between vertebrae L4 and L5 is identified as the L4/L5 IV disc)
• thoracic IV discs are relatively thin and uniform in shape
• cervical and lumbar IV discs are thicker anteriorly (contributing to the secondary curvatures of the vertebral column and making these regions more susceptible to herniation)

Question 24

What are the Components of an IV disc?

Answer 24

• anulus fibrosus: Outer fibrocartilaginous ring
• nucleus pulposus: Gelatinous central mass. high water content that decreases during the day and with aging. shock absorption: absorbs and evenly distributes forces

Question 25

What are the different Joints of the Vertebral Column?

Answer 25

1) Cartilaginous (symphyses) joints, consisting of IV discs & ligaments 2) Uncovertebral joints (of Luschka) 3) Facet (zygapophysial) joints 4) Atlanto-occipital joints 5) Atlanto-axial joints

Question 26

Describe the Uncovertebral joints (of Luschka)

Answer 26

- located between uncinate processes of cervical vertebrae and body of adjacent vertebrae - site of bone spur formation, causing neck pain

Question 27

Describe the Facet (zygapophysial) joints

Answer 27

- synovial joints between articular processes of adjacent vertebrae - orientation of facet joints helps determine mobility of region, permitting gliding movements between vertebrae - Cervical articular facets face superiorly and inferiorly, permit flexion/extension, lateral flexion, and rotation - Thoracic articular facets face anteriorly and posteriorly, permit rotation and restrict flexion/extension and lateral flexion; note: the inferiorly directed spinous processes also limit extension while the attachments to the ribs also limit flexion/extension and lateral flexion - Lumbar articular facets face medially and laterally, permit flexion/extension and lateral flexion and restrict rotation

Question 28

Describe the Atlanto-occipital joints

Answer 28

- synovial joints between the superior articulating processes of the atlas (C1) and the occipital condyles of cranium - primary motion is flexion/extension of the head (nodding the head as in indicating “yes”)

Question 29

Describe the Atlanto-axial joints

Answer 29

- synovial joints between atlas (C1) and axis (C2) - primary motion is rotation of the head (as in indicating “no”) - two lateral atlanto-axial joints (facet joints) - median atlanto-axial joint (synovial joint between the anterior arch of the atlas, the dens process, and the transverse ligament of the atlas)

Question 30

What is the Surface Anatomy of the Back? (Osteological landmarks)

Answer 30

- external occipital protuberance of the occipital bone - mastoid processes of the temporal bones - spinous processes, including vertebra prominens (C7) - inferior angle of the scapula (T7 vertebral level) - iliac crests (L4 vertebral level)

Question 31

Describe nerve and blood supply to the skin of the Back

Answer 31

- segmental nerve supply via dorsal rami (recall that dorsal rami include motor and sensory fibers; e.g., somatic motor fibers, sympathetic fibers, & somatic sensory fibers) - blood supply and drainage via segmental vessels (e.g., branches of intercostal arteries/veins, lumbar arteries/veins)

Question 32

Describe the Nuchal ligament (Ligamentum nuchae)

Answer 32

-cervical thickening of the supraspinous ligament (which runs along the spinous processes along the length of the vertebral column) -attaches superiorly to external occipital protuberance and inferiorly to spinous processes of cervical vertebrae site of muscle attachment

Question 33

Describe the Thoracolumbar fascia

Answer 33

- dense sleeve of fascia in thoracic and lumbar regions - site of muscle attachment (e.g., latissimus dorsi) - surrounds the intrinsic back muscles (see below)

Question 34

Describe innervation to the (Superficial) Muscles of the Back

Answer 34

Innervated by ventral rami (exception: Trapezius is innervated by cranial nerve XI, the spinal accessory nerve)

Question 35

What are the extrinsic muscles acting on the upper extremity?

Answer 35

- Trapezius - Latissimus dorsi - Levator scapulae - Rhomboid minor and Rhomboid major

Question 36

What is the triangle of auscultation?

Answer 36

The triangle of auscultation is a small region, free of overlying superficial muscles, bounded by trapezius, latissimus dorsi, and the scapula. The lack of muscle in this area allows for more efficient use of a stethoscope to listen to sounds in the thoracic cavity.

Question 37

What are the two extrinsic muscles involved in respiration?

Answer 37

- serratus posterior superior - serratus posterior inferior these muscles are located deep to the rhomboids and latissimus dorsi, respectively

Question 38

Describe innervation, functions, and other facts about the Intrinsic (Deep) Muscles of the Back

Answer 38

- Innervated by dorsal rami - Longitudinal columns of muscle, extending from the pelvis to the cranium - Thoracic and lumbar portions are enclosed by the thoracolumbar fascia - Functions: primary function is extension of the vertebral column, with lateral flexion and rotation as secondary functions - Commonly injured

Question 39

What makes up the Superficial layer of the Intrinsic (Deep) Muscles of the Back

Answer 39

Splenius capitis & splenius cervicis -Origin: nuchal ligament, thoracic spinous processes -Insertion: mastoid process, occipital bone (capitis) cervical transverse processes (cervicis) -Actions: extend neck (when contracting bilaterally) lateral flexion & rotation of neck to ipsilateral side (when contracting unilaterally)

Question 40

What makes up the Intermediate layer of the Intrinsic (Deep) Muscles of the Back

Answer 40

Erector spinae 3 columns (from lateral to medial): • Iliocostalis (lumborum, thoracis, and cervicis portions) • Longissimus (thoracis, cervicis, and capitis portions) • Spinalis (thoracis, cervicis, and capitis portions) -Origin: iliac crest, sacrum, lumbar spinous processes -Insertion: Iliocostalis: ribs, transverse processes Longissimus: transverse processes, mastoid process Spinalis: spinous processes, occipital bone -Actions: extend vertebral column (when contracting bilaterally); lateral flexion & rotation of vertebral column to ipsilateral side (when contracting unilaterally)

Question 41

What makes up the Deep layer of the Intrinsic (Deep) Muscles of the Back

Answer 41

Transversospinalis 3 parts (from superficial to deep): • Semispinalis (thoracis, cervicis, and capitis portions; most prominent in cervical region) • Multifidus (lumborum, thoracis, and cervicis portions; most prominent in lumbar region) • Rotatores (lumborum, thoracis, and cervicis portions; most prominent in thoracic region) -Origin/Insertion: Occupy “gutter” between transverse and spinous processes -Actions: extend vertebral column (when contracting bilaterally); stabilize vertebrae; rotation to contralateral side (when contracting unilaterally)