Upper Limb Nerve Injuries

Question 1

The roots of the brachial plexus comes from which rami?

Answer 1

Ventral Rami C5-T1

Question 2

The roots of the brachial plexus are located where?

Answer 2

Deep to the anterior scalene muscle (ASM)

Question 3

Where do the ventral primary rami unite to for the 3 trunks?

Answer 3

at the lateral border of the ASM

Question 4

The anterior division of the trunks supply what?

Answer 4

Anterior muscles and skin of the upper limb

Question 5

The posterior division of the trunks supply what?

Answer 5

Posterior muscles and skin

Question 6

When entering the axilla, the divisions pass deep to what?

Answer 6

The clavicle

Question 7

Where does the brachial plexus end?

Answer 7

In the axilla as cords give rise to main nerve branches of the upper limb

Question 8

Anterior medial arm/forearm cutaneous innervation

Answer 8

Medial cutaneous nerves of the medial cord

Question 9

Anterior lateral forearm cutaneous innervation

Answer 9

Continuation of the musculocutaneous nerve, which is the lateral ante brachial cutaneous nerve

Question 10

Posterior medial arm cutaneous innervation

Answer 10

Medial brachial cutaneous nerve

Question 11

Posterior medial forearm cutaneous innervation

Answer 11

Medial antebrachial cutaneous (C8, T1)

Question 12

Posterior lateral forearm cutaneous innervation

Answer 12

Continuation of the musculocutaneous nerve, which is the lateral ante brachial cutaneous nerve

Question 13

Anterior lateral arm cutaneous innervation

Answer 13

Axillary near deltoid

Radial - under axillary innervation

Question 14

Posterior lateral arm/forearm cutaneous innervation

Answer 14

Axillary near deltoid

Radial the rest of the way down

Question 15

What is cutaneous innervation?

Answer 15

based on clinical findings in a living person

Question 16

Dermatomes

Answer 16

Based on development
Surface of the skin is divided into specific areas (connective tissue, including dermis)
derived from somites

Question 17

What is segmental innervation?

Answer 17

A dermatome is an area of skin in which sensory nerves derive from a single spinal nerve root

Question 18

Avulsion

Answer 18

most sever type

Nerve is torn from spine (pull the root of the brachial plexus out the neck)

Question 19

Rupture

Answer 19

nerve is torn but not at the spinal attachment (nerve stretched and ruptured in two parts

Question 20

Neuroma

Answer 20

nerve has torn and healed but scar tissue puts pressure on injured nerve and prevents it from conduction signals to muscles

Question 21

Neuropraxia

Answer 21

Stretched

Nerve has been damaged but not torn

Most common type of of brachial plexus injury

Question 22

Most severe brachial plexus injuries are caused by which two events?

Answer 22

Car and motorcycle accidents

these can leave arm paralyzed, with loss of function and sensation

Question 23

For avulsion and rupture injuries, can they be repaired?

Answer 23

there is no potential for recovery unless surgical reconnection is made in a timely manner

Question 24

For neuroma and neuropraxia, can they be repaired?

Answer 24

potential for recovery varies

Most people with neurpraxia injuries recover spontaneously with a 90-100% return of function

Question 25

Stingers/burners

Answer 25

Minor brachial plexus injuries common causes: contact sports Stinger -> compression or over-stretching of nerves

Question 26

Root injury

Answer 26

lateral flexion of neck toward the side of symptoms | - foraminal narrowing (compression), especially in the presence of an underlying disc herniation or osteophyte

Question 27

Plexus injury

Answer 27

neck and upper trunk vulnerable to direct blows or stretching from distraction of neck away from shoulder

Question 28

What are the two nerve roots that are most commonly affected?

Answer 28

C5 and C6

Question 29

Erb's palsy

Answer 29

Paralysis of upper brachial plexus (C5, C6) > Upper trunk damaged

Question 30

What are the most commonly involved nerves of Erb's Palsy?

Answer 30

Suprascapular (C5-C6) - Paralysis of muscles Musculocutaneous (C5-C7) - Paresis of muscles Axillary (C5-C6) - Paralysis of muscles

Question 31

If roots are damaged above the junction of C5 and C6 what results?

Answer 31

paralysis of rhomboids (dorsal scapular n.) and serratus anterior (long thoracic n, C5-C7) is added, producing weakness in retraction and protraction the scapula

Question 32

What is the most common area for the upper brachial plexus to be damaged?

Answer 32

Upper trunk

Question 33

What are the nerves that only contains C5 and C6 nerve fibers?

Answer 33

Axillary nerve Lower subscapular Upper subscapular

Question 34

What is the characteristic sign of Erbs Palsy?

Answer 34

Waiters tip deformity Arm - rotated medially (loss of lateral rotators of the shoulder- rotator cuff muscles) Arm - hangs (lack of abduction - deltoid and supraspinatis Forearm - extended and pronated (weakness of arm flexors and biceps; weak supinator - C5-C6 radial nerve)

Question 35

What is Klumpke's Palsy? and it's symptoms?

Answer 35

Paralysis of the lower brachial plexus (C8, T1) Symptoms: Claw hand, severe pain, loss sensation, dermatome numbness

Question 36

What are the affected nerves in Klumpke's Palsy?

Answer 36

``` medial pectoral nerve Medial brachial cutaneous Medial antebrachial cutaneous Ulnar n. (main nerve affected) Radial n. Median n. ```

Question 37

What is claw hand?

Answer 37

Affected forearm tends to lie flat and the wrist and fibers are tightened Hyperextension of the hand at the metacarpalphalangeal jointed flexion of the hand at the interphalangeal joint

Question 38

What are the muscles paralyzed in Klumpke's palsy?

Answer 38

Flexor carpi ulnaris Medial half of flexor digitorium profundus most intrinsic hand muscles (ulnar) Pecotralis minor (medial pectoral nerve)

Question 39

How do you test for Erb's Palsy

Answer 39

Weakness in supinator Radial nerve affected (C5-T1)

Question 40

How do you test for Klumpke's palsy?

Answer 40

check intrinsic hand muscles Flexors of the wrist and fingers Check lumbrical function Looking to see if ulnar (C8,T1) and median nerve (C5-T1) is ok