3.1- Spinal Cord Injury

Question 1

SCI Stats:

1. ____ new cases/year with 200,000 living in US
2. Most likely ages ___ but adults 61+ make up 10% of population (falls)
3. ____% male
4. What is the most common cause?

Answer 1

1. 10,000
2. 16-30
3. 82%
4. MVA 33%, Violence 27%, Falls 21%, Sports 6%

Question 2

Total of ___ pairs of spinal nerves:

\_\_\_ cervical
\_\_\_ thoracic
\_\_\_ lumbar
\_\_\_ sacral
\_\_\_ coccyx

Answer 2

31 pairs: 8 cervical, 12 thoracic, 5 lumbar, 5 sacral, 1 coccyx

Question 3

First cervical spinal nerve has only ____ roots - ____ but no ___ components.
Sensory of face and head is supplied by _____ nerve instead.

Answer 3

ventral roots- motor but no sensory

trigeminal nerve

Question 4

8 cervical spinal nerves- pair 1-7 exit ___ the cervical vertebrae of the same number while C8 exits ______
*All remaining spinal nerves exit ___ their vertebrae to ____

Answer 4

1-7 exit above

C8 exits below C7 and above T1

remaining spinal nerves exit below their vertebrae to T12

Question 5

The SC ends at the ____ disc- after birth the spinal column grows while the cord does not.

Answer 5

L1-L2 disc

Question 6

In the upper cervical region the nerves exit _______.
By the end of the cervical spine the nerve has to drop _____ before it exits.
Thoracic nerve roots must drop ___ level; difference is so great at the lumbar level that it must drop ___ levels.

Answer 6

upper cervical = at the level of the vertebrae

end of cervical spine = drop 1 level

thoracic roots = drop 1 level

lumbar level = must drop 2 levels

Question 7

Naming an injury:

named according to the _______ (as demonstrated by muscle function that remains), not level of bony damage

Answer 7

the last spinal nerve left intact

Question 8

Naming an injury:
Because the nerve root drops before it exits, the person will generally have function ____ than the level that the actual bony injury occurred.

Answer 8

lower

Question 9

Naming an injury:

Damage from _____ generally affects the ______, not the spinal cord

Answer 9

L1 and down generally affects the cauda equina

Question 10

_______ - caudal most segment with intact sensory and motor function

• intact muscle function is determined by having at least a Fair MMT if others above are Good to Normal
• key muscles used for testing are the ones most used functionally

Answer 10

Neurologic level of injury

Question 11

What is determined by testing key myotomes and dermatomes?

Answer 11

Neurologic level of injury

Question 12

Naming an injury:
Because a muscle can be innervated by ______ and neurologic damage is generally _____, some function is likely below the level of damage.

Answer 12

innervated by more than 1 level and neurologic damage is generally not complete

Question 13

What is:
Quadriplegia or Tetraplegia?

Paraplegia?

Cauda Equina lesion?

Answer 13

Quad or Tetra = cervical injury that affects all 4 limbs

Para = thoracic injury involving lower limbs

Cauda Equina lesion = L1 and below

Question 14

The SC is thicker in an area of more _______ function. Why?

Answer 14

motor function b/c of the large number of motor neurons

Question 15

C1, C2; Lots of rotation = _____

C5-C7 make up the ______ a.k.a. the ________

T12-L2 make up the _____ a.k.a. the ________

Answer 15

C1, C2 = instability

C5-C7 = Brachial plexus, a.k.a. the cervical enlargement

T12-L2 = lumbar plexus, aka the lumbar enlargement

Question 16

Why are enlarged (cervical enlargement and lumbar enlargement) areas more vulnerable to injury?

Answer 16

b/c the cells take up so much room that it can’t move out of the way and tend to be more mobile making them less stable

Question 17

What are 4 common spinal cord injuries?

Answer 17

1. cervical flexion and rotation injuries
2. compression injury
3. hyperextension
4. hyperflexion injury

Question 18

What are 3 facts about cervical flexion and rotation injuries?

Answer 18

1. occurs with MVA when struck from rear
2. posterior spinal ligament ruptures and the upper vertebrae can displace on the lower transecting the SC
3. disc can also rupture damaging the SC

Question 19

What are 2 facts about compression injuries?

Answer 19

1. occurs with downward compressive force such as diving, falls from high surfaces, severe osteoporosis
2. fracture of the vertebral body producing bone fragments that get displaced into SC- or body is completely crushed putting pressure on the SC

Question 20

What are 2 facts about hyperextension injuries?

Answer 20

1. common in falls of the elderly when chin strikes a stationary object
2. anterior longitudinal ligament ruptures, disc can rupture and SC is compressed

Question 21

What are 2 facts about hyperflexion injuries?

Answer 21

1. caused by head on collision or blow to back of head

2. anterior compression fracture of vertebral body causing disc tearing and damage to the anterior spinal artery

Question 22

What type of SCI?

1. posterior spinal ligament ruptures
2. damage to the anterior spinal artery
3. anterior longitudinal ligament ruptures
4. fracture of vertebral body

Answer 22

1. cervical flexion and rotation injuries
2. hyperflexion injury
3. hyperextension
4. compression injury

Question 23

What happens immediately have SCI?
1.
2.
3.

Answer 23

1. hemorrhage into gray matter of SC causing necrosis
2. edema develops putting pressure on tracts interrupting signals from both sensory and motor
3. spinal shock

Question 24

What causes spinal shock and how long does it normally last?

What are some symptoms?

Answer 24

due to interruption of autonomic pathways, normally lasts 24-48 hours, but may go on weeks

flaccid, areflexia, loss of bowel and bladder function, decreased BP, and poor temp regulation below the level of injury

Question 25

What happens 6-12 hours after SCI?

What happens 1 week after SCI?

Answer 25

6-12 hours = immune cells respond and attempt to clean up tissue - results in destruction of more tissue

1 week = fibers begin to loose myelin affecting ability to conduct