Back Osteology

Question 1

The axis (C2) is susceptible to fracture in two places. What are these two spots?

Answer 1

The odontoid process (dens) and vertebral arch

Question 2

What is a Hangman’s fracture?

Answer 2

Fracture of the vertebral arch or odontoid process of the axis (C2)

Question 3

A hangman’s fracture of the vertebral arch occurs as a result of what?

Answer 3

Hyperextension of the head on the neck

Question 4

A hangman’s fracture of the odontoid process occurs after what?

Answer 4

A horizontal blow to the head and since the transverse L is stronger than the odontoid process it breaks

Question 5

What is a type I odontoid fracture?

Answer 5

If the tip of the odontoid process is fractured

Question 6

What is a type II odontoid fracture?

Answer 6

The entire dens is broken off

Question 7

What is a type III odontoid fracture?

Answer 7

Dens + part of the vertebral body is broken off

Question 8

When will an odontoid fracture not heal?

Answer 8

If the odontoid process breaks at its base because the transverse L is holding it away from its blood supply

Question 9

When is the odontoid process much more likely to heal after fracture?

Answer 9

If the odontoid process breaks at the inferior to the base

Question 10

What is a Jefferson or burst fracture?

Answer 10

Fracture of both arches of the atlas due to a blow to the top of the head from a falling object or driving accident

Question 11

Does a Jefferson fracture injure the spinal cord?

Answer 11

Not typically however if the transverse L is ruptured to odontoid process may injure the spinal cord

Question 12

Explain why it takes less force to dislocate cervical vertebra?

Answer 12

Since the articulating facets are most horizontal compared to other vertebra it takes less force to dislocate cervical vertebra
However due to the large vertebral foramen this doesnt usually result in injury to the spinal cord

Question 13

What is spina bifida occulta?

Answer 13

A bony defect that occurs in 24% of the population

A developmental abnormality in which the vertebral lamina fails to fuse and close off the vertebral canal

Question 14

Where does spina bifida occulta commonly occur?

Answer 14

At L5 and S1 where it can go undetected due to the overlying skin
Often a tuft of hair exists over the defect

Question 15

What is spina bifida cystica?

Answer 15

A form of spina bifida that also incorporates neural tissue and meninges

Question 16

What is spondylosis?

Answer 16

A degenerative joint disease which involves calcification of the edges of the vertebral body and can cause localized pain and stiffness

Question 17

What is spondylolysis?

Answer 17

Separation of the vertebral arch from the vertebral body

Question 18

What is spondylolisthesis?

Answer 18

Anterior displacement of the vertebral body on the inferior vertebral segment

Question 19

What can occur secondary to spondylolysis?

Answer 19

Spondylolisthesis

Question 20

What is lumbar spinal stenosis?

Answer 20

Narrowing of the lumbar vertebral foramen

May cause compression of one or more spinal nerve roots

Question 21

What happens when lumbar spine stenosis is further compounded with intervertebral disc bulging?

Answer 21

Arthritic proliferation and ligamentous degeneration of the vertebral canal is considerably more compromised

Question 22

What is a lumbar puncture (spinal tap)?

Answer 22

An important diagnostic procedure for evaluating a variety of CNS disorders

Question 23

Describe how a lumbar puncture is performed

Answer 23

A needle is inserted between either L3/4 or L4/5 at the level of the iliac crests
As the needle passes through the ligamentum flavum it “pops” and passes into the lumbar cistern deep into the spinal dura and arachnoid mater
CSF can then be drawn out and evaluated for CNS disorders

Question 24

Why is a lumbar puncture typically done at the levels of L3/4 or L4/5?

Answer 24

To avoid the needle injuring the spinal cord

Question 25

What is sacrilization of L5 (hemisacrilization)?

Answer 25

The partial or complete incorporation of the L5 vertebral segment into the sacrum

Question 26

What is lumbarization of S1?

Answer 26

The separation of the S1 vertebra from the sacrum

Question 27

What is coccygeal trauma?

Answer 27

May occur due to low falls on the lower back or difficult child birth
Results in bruising, dislocation or fracture of the coccyx
Coccygodynia (pain) can follow trauma
Painful and difficult to treat

Question 28

What are the primary curvatures of the vertebral column?

Answer 28

The thoracic and sacral kyphoses

Question 29

What are the secondary curvatures of the vertebral column?

Answer 29

The cervical and lumbar lordoses as they result from extension from the fetal position

Question 30

What is an exaggerated kyphosis?

Answer 30

Exaggerated curving of the thoracic vertebral column resulting in hump back

Question 31

What is an exaggerated lordosis?

Answer 31

Refers to exaggerated curving of the lumbar vertebral column resulting in sway back

Question 32

What is scoliosis?

Answer 32

Refers to lateral curving of the spine either to the right or left

Question 33

What are features of a typical vertebra?

Answer 33

Lamina, spinous process, transverse process, vertebral arch, vertebral foramen, vertebral body, pedicle, vertebral notch and articulating processes

Question 34

What are some unique features of cervical vertebra?

Answer 34

Bifed spinous process, large triangular vertebral foramen, anterior and posterior tubercles on transverse processes, uncinate processes, transverse foramen and costotransverse bar

Question 35

What are some unique features of thoracic vertebra?

Answer 35

Small round vertebral foramen, well pronounced lamina, heart shaped vertebral body, superior, transverse and inferior costal facets, and strongly inferiorly directed spinous process

Question 36

What are some unique features of lumbar vertebra?

Answer 36

Large oval shaped vertebral foramen, long slender transverse process, large kidney shaped vertebral body, mammillary process, accessory process and short sturdy hatchet shaped spinous process