Spine Trauma, part 2

Question 1

The vertebral column is composed of

Answer 1

33 vertebrae:
7 cervical
12 thoracic
5 lumbar
5 fused sacral
4 (usually fused) coccygeal

Question 2

Overall the most commonly injured region of the spinal column

Answer 2

Cervical spine
due to its inherent flexibility
with most injuries occuring at the C2 level and from C5 to C7

Question 3

2nd most common region of injury of the spinal column

Answer 3

Thoracolumbar transition zone (T11 to L2)

Question 4

The spinal cord gives rise to _____ pairs of spinal nerves

Answer 4

31 pairs of spinal nerves
8 cervical
12 thoracic
5 lumbar
5 sacral
1 coccygeal

Question 5

The lower nerve roots form an array of nerves called

Answer 5

the cauda equina (“horse’s tail”)

Question 6

These zones sustain the greatest amount of stress during motion

Answer 6

The transitional zones
They are the most vulnerable to injury

Question 7

Remarks on thoracic vertebral injury

Answer 7

The presence of a thoracic vertebral injury indicates the patient was subjected to severe traumatic forces and is at high risk for intrathoracic injuries

Moreover, the spinal canal in the thoracic region is also narrower than in other regions. This increases the risk of cord injury, which is often complete when it occurs.

Question 8

Remarks on the thoracolumbar region

Answer 8

Relative to the thoracic spine, the width of the spinal canal in the thoracolumbar region is greater. Therefore, despite a large number of vertebral injuries at the thoracolumbar junction, most do not have neurologic deficits, or if present, they are partial or incomplete

Question 9

Remarks on sacral fractures

Answer 9

Sacral fractures that involve the central sacral canal can produce bowel or bladder dysfunction.

Question 10

Remarks on spinal stability

Answer 10

1. Spinal stability is defined as the ability of the spine to limit patterns of displacement under physiologic loads so as not to damage or irritate the spinal cord or nerve roots
2. A spine injury is considered unstable if at least two columns (i.e., anterior, middle, or posterior elements) of a particular region are involved.
3. Determining spinal stability after an acute injury in the ED is particularly difficult.
   - these injuries often occur in the setting of polytrauma, altered mental status, and severe pain, which may result in suboptimal initial imaging.
   - EDs lack quick access to emergent MRI to evaluate the spinal ligaments
4. Therefore, assume any spine fracture is unstable, and maintain appropriate precautions until expert consultation can be obtained from a spine surgon

Question 11

Remarks on spinal shock

Answer 11

Patients in spinal shock lose all reflex activities below the area of injury, and lesions cannot be deemed truly complete until spinal shock has resolved.

Question 12

Remarks on pain and temperature sensory loss

Answer 12

The pain and temperature sensory loss begins one or two segments below the level of damage

Question 13

Remarks on injury to the dorsal columns

Answer 13

1. Injury to one side of the dorsal columns will result in ipsilateral loss of vibration and position sense.
   - The sensory loss begins at the level of the lesion
2. Light touch is trasmitted through both the spinothalamic tracts and the dorsal columns.
   - Therefore, light touch is not completely lost unless there is damage to both the spinothalamic tracts and the dorsal columns

Question 14

Termination of the spinal cord

Answer 14

The adult spinal cord ends as the conus medullaris at the level of the lower border of the first lumbar vertebra.

Question 15

Remarks on spinal immobilization

Answer 15

1. Prehospital care for spinal injuries traditionally involves immobilization of the entire spine at the scene with a rigid cervical collar (or similar device) plus a long backboard
2. However, there is little evidence that cervical collars and/or long spine boards reduce neurologic injury, spinal instability, or mortality
3. Recommendations still state the use of rigid cervical collars and that the long board should only be used as an extrication device and not during transport.
4. Spinal immobilization is NOT recommended for fully conscious, neurologically intact patients with isolated penetrating neck injury because collars delay resusctation and obscure neck injjuries

Question 16

Remarks on manual in-line stabilization

Answer 16

1. Given the unclear benefit of cervical collars, do not hesitate to substitute manual in-line stabilization if collar is compromising the airway.
2. Maintain manual in-line spinal stabilization while intubating = less cervical motion and better glottis visualization
3. Videolaryngoscopes improve visualization in cervical immobilized patients and may reduce failed intubations, but manual in-line stabilization is still recommended to minimize cervical motion

Question 17

Remarks on bradycardia in a hypotenive trauma patient

Answer 17

Although hypotension and relative bradycardia are classic signs of neurogenic shock, bradycardia can also be associated with intraperitoneal bleeding or prior medication with calcium channel blockers or beta blockers

Question 18

Remarks on cervical collars

Answer 18

1. Hard cervical collars are associated with patient discomfort and pressure sores of the neck. Therefore, promptly clear the cervical spine if possible
2. Do not overtighten the cervical collar on head-injured patients, because jugular venous compression can raise ICP, although **Stifneck® and Miami J® collars may be better than other rigid collars in this regard.
3. Avoid physically fighting with an agitated patient in a forcible attempt to place a cervical collar, as overly aggressive attempts to restrain a patient may possibly cause or exacerbate a cervical injury

Question 19

Symptoms that may indicate a high cervical injury

Answer 19

Symptoms indicating present or impending respiratory compromise
- dyspnea
- palpitations
- abdominal breathing
- anxiety

Question 20

Saddle anesthesia

Answer 20

Sensory deficit in the region of the buttocks, perineum, and inner aspect of the thighs

Question 21

Bulbocavernosus reflex

Answer 21

1. This istested by squeezing the penis to determine whether the anal sphicter simultaneously contracts
2. Sacral sparing or reservation of anogenital reflexes denotes an incomplete spinal cord level, even if the patietn has complete sensory and motor loss

Question 22

Priapism implies

Answer 22

a complete spinal cord injury

Question 23

Mechanisms of injury that result in anterior cord syndrome

Answer 23

1. Direct injury to the anterior spinal cord
2. Flexion of the cervical spine may result in cord contusion or bone injury with secondary cord injury
3. Thrombosis of the anterior spinal artery can cause ischemic injury to the anterior cord

Question 24

The central cord syndrome is usually seen in

Answer 24

older patients with preexisting cervical spondylosis who sustain a hyperextension injury

Question 25

Incomplete spinal cord syndrome with a poor prognosis

Answer 25

Anterior cord syndrome
The overall prognosis for recovery of function is poor.

Question 26

Cauda equina syndrome

Answer 26

1. Cauda equina syndrome is not a true spinal cord syndrome because the cauda equina is composed entirely of lumbar, sacral, and coccygeal nerve roots; therefore, injuries to this region produce peripheral nerve injuries
2. Symptoms and signs may include bowel and/or bladder dysfunction, decreased anal shincter tone, “saddle anesthesia”, variable motor and sensory loss in the lower extremities, decreased lower extremity reflexes, and sciatica.
3. No one symptom or sign has 100% predictive value for this entity, therefore, perform an emergent MRI of the lumbosacral spinal cord if clinicial suspicion warrants.