Peripheral Nerve Injuries

Question 1

What are peripheral nerves involved in?

Answer 1

Signal transmission between the spinal cord and body.

Question 2

Name the three connective tissue coverings of peripheral nerves.

Answer 2

Endoneurium, perineurium, epineurium.

Question 3

What components make up a peripheral nerve?

Answer 3

Nerve fibers, connective tissues, and blood vessels.

Question 4

What characterizes a peripheral nerve fiber?

Answer 4

Axon, neurolemma, endoneural connective tissue.

Question 5

Which cells are crucial in the peripheral nervous system?

Answer 5

Neuronal, glial, stromal cells.

Question 6

What do Schwann cells contribute to?

Answer 6

Myelination and support in peripheral nerves.

Question 7

What is neuropraxia?

Answer 7

Temporary conduction block without axonal damage.

Question 8

How does axonotmesis differ from neuropraxia?

Answer 8

Axonal damage occurs, connective tissue remains intact.

Question 9

What defines neurotmesis?

Answer 9

Complete nerve severance and sheath damage.

Question 10

What is the prognosis for neuropraxia?

Answer 10

Full recovery within days to weeks.

Question 11

What process enables recovery in axonotmesis?

Answer 11

Axonal regeneration, up to one inch per month.

Question 12

What is a traumatic neuroma?

Answer 12

Painful thickening due to nerve regeneration.

Question 13

What are common symptoms of neurotmesis?

Answer 13

Pain, dysesthesias, complete motor/sensory loss.

Question 14

Name three mechanisms of peripheral nerve recovery.

Answer 14

Wallerian degeneration, axonal regeneration, reinnervation.

Question 15

What triggers Wallerian degeneration?

Answer 15

Axonal damage or severance.

Question 16

How does compression injury typically manifest?

Answer 16

As neuropraxia, often short-term.

Question 17

What is ‘double crush syndrome’?

Answer 17

Increased susceptibility to neuropathy from multiple lesions.

Question 18

What is the main role of glial cells in PNS?

Answer 18

Support and protection of neurons.

Question 19

How long does motor unit collateral branching continue post-injury?

Answer 19

3-4 months.

Question 20

What characterizes sensory deficits in peripheral nerve injury?

Answer 20

Poorly localized, non-specific pain.

Question 21

What factors influence axonal regeneration speed?

Answer 21

Distance from the injury site.

Question 22

What type of injury leads to burner/stinger syndrome?

Answer 22

Traction injuries of peripheral nerves.

Question 23

Which nerves are frequently injured in fractures?

Answer 23

Radial, common peroneal, axillary nerves.

Question 24

What is a common site of compression injuries?

Answer 24

Narrow anatomical openings.

Question 25

How does ischemia affect nerve function?

Answer 25

Causes conduction block due to lack of blood supply.

Question 26

Which classification describes the mildest form of nerve injury?

Answer 26

Neuropraxia.

Question 27

What leads to chronic pain in peripheral nerve injuries?

Answer 27

Incomplete recovery and traumatic neuromas.

Question 28

What is the function of motor neurons in peripheral nerves?

Answer 28

Convey signals to muscles for movement.

Question 29

What is the role of sensory neurons?

Answer 29

Transmit sensory information to the brain.

Question 30

What distinguishes autonomic neurons in peripheral nerves?

Answer 30

Regulation of involuntary bodily functions.