Special Populations/Nerve Injuries

Question 1

Peripheral Neural Structures include:

Answer 1

Muscle spindles
Golgi tendon organs
Motor endings in muscle
Axons

Question 2

Dorsal rami

Ventral rami

Answer 2

Innervates posterior

Innervates anterior and lateral

Question 3

Rami communicantes connect with….

Answer 3

Sympathetic ganglia

Question 4

Layers of peripheral nerve

superficial to deep

Answer 4

Mesoneurium
External epineurium
Internal epineurium
Perioneurium
Endoneurium
Axon

Question 5

Large/Medium myelinated axon examples:

Answer 5

Efferent: Extrafusal/Intrafusal muscle fibers
Afferent: Spindles, Golgi tendon organs, pressure receptors

Question 6

Small myelinated axon examples:

Answer 6

Efferent: presynaptic autonomic
Afferent: pain, temperature, visceral receptors

Question 7

Unmyelinated axons examples:

Answer 7

Efferent: postsynaptic autonomic
Afferent: pain, temperature, visceral receptors

Question 8

Fastest conduction

Answer 8

Large myelinated > Medium myelinated > Small myelinated > Unmyelinated

Question 9

Mechanisms for nerve injury

Answer 9

1. Compression
2. Laceration
3. Stretch
4. Radiation
5. Electricity

Question 10

Seddon’s Classification for Nerve Injuries

Answer 10

1. Neurapraxia
2. Axonotmesis
3. Neurotmesis

Question 11

Neurapraxia

Answer 11

Typically leads to full recovery
Intact structural nerve
Commonly results from compression or ischemia

Question 12

Axonotmesis

Answer 12

May result in recovery of sensory/motor ability (if neuronal tubules are maintained)
Axon disruption, myelin sheath intact
commonly results from compression injury

Question 13

Neurotmesis

Answer 13

None or difficult to full recovery

Damage to nerve trunk (epineurium)

Question 14

Compression of spine leads to….which can cause damage to….

Answer 14

Narrowed Intervertebral foramen…….nerve roots

Question 15

Upper limb syndromes that cause nerve injuries:

1. Brachial plexus
2. Ulnar nerve
3. Radial nerve
4. Medial nerve

Answer 15

1. Thoracic Outlet Syndrome
2. Cubital Tunnel Syndrome, Compression of Guyon’s Tunnel
3. Radial Nerve Compression
4. Carpal Tunnel Syndrome

Question 16

Lower limb syndromes that cause nerve injuries

1. Sciatic nerve
2. Peroneal nerve
3. Tibial nerve

Answer 16

1. Piriformis Syndrome
2. Peroneal Nerve Compression
3. Tarsal Tunnel Syndrome

Question 17

Upper brachial plexus injury s/s

Answer 17

C5, C6
Loss of abduction, ER
Weakness in flexion, supination

Question 18

Lower brachial plexus injury s/s

Answer 18

C8 T1

Paralysis of intrinsic hand muscles

Question 19

Axillary nerve s/s

Answer 19

C5, C6
Deltoid muscle atrophy > square shoulder
Abduction, ER weakness
Sensory: lateral deltoid

Question 20

Musculocutaneous nerve s/s

Answer 20

C5, C6, C7
Atrophy of arm flexors
Elbow flexion w/ supination weakness
Sensory: radial side of forearm

Question 21

Median nerve s/s

Answer 21

C6-C8, T1