Lecture 12 - Brachial Plexus Lesions

Question 1

Provides innervation to anterior arm

Becomes lateral cutaneous nerve of forearm

Answer 1

Musculocutaneous (C5,6,7)

Question 2

Innervates anterior compartment of the forearm-except flexor carpi ulnaris and part of the flexor digitorum profundus (ulnar)
Innervates thenar muscles and lateral two lumbricals in the hand

Answer 2

Median (C6-T1)

Question 3

Innervates some forearm muscles and medial hand

Answer 3

Ulnar (C8-T1)

Question 4

Innervates posterior aspect of upper extremity

Answer 4

Radial (C5-T1)

Question 5

Innervates deltoid, teres minor, long head of triceps

Answer 5

Axillary (C5,6)

Question 6

Nerves that branch off at root level

Answer 6

• Dorsal Scapular nerve (C5)

- Long thoracic nerve (C5, C6, C7)

Question 7

Nerves that branch off at trunk level

Answer 7

-Suprascapular nerve (C5, C6)
to supraspinatus and infraspinatus
-Subclavius (C5)

Question 8

Nerves that branch off at cord level

Answer 8

• Lateral (C5,6,7) and medial (C8,T1) pectoral nerves to pectoralis major; the medial pectoral nerve also supplies pectoralis minor
• Upper subscapular nerve (C5,6) to subscapularis
• Middle subscapular /thoracodorsal nerve (C6,7,8) to latissimus dorsi
• Lower subscapular nerve (C5,6) to subscapularis and teres major

Question 9

Type of nerve lesion:

nerve is torn from the spine

Answer 9

Avulsion

Question 10

Type of nerve lesion:

nerve is torn but not at the spinal attachment

Answer 10

Rupture

Question 11

Type of nerve lesion:
nerve has torn and healed but scar tissue puts pressure on the injured nerve and prevents it from conducting signals to the muscles

Answer 11

Neuroma

Question 12

A stretch, in which the nerve has been damaged but not torn

The most common type of brachial plexus injury

Answer 12

Neuropraxia

Question 13

injuries caused by trauma to the neck and shoulder that result in a burning pain that travels down the arm
often accompanied by numbness and weakness
Either the head and neck are forced toward the shoulder, compressing the nerves that lead from the spinal cord to that arm, or the head and neck are forced away from the shoulder, stretching those nerves
Symptoms are usually short-lived, but severe injuries can last for weeks or months

Answer 13

The “Burner” (AKA: “Stinger”)

Question 14

Paralysis of the UPPER brachial plexus
Caused by stretching at neck & shoulder (as in a fall or commonly during birth)
Chronic micro trauma from heavy backpack can cause deficits
Manifests as adducted shoulder, extended elbow, with medial rotation
Places hand in “waiter’s tip” position
C5-C6

Answer 14

Erb-Duchenne Palsy

Question 15

Paralysis of the LOWER brachial plexus
Occurs when upper limb is pulled superiorly
Intrinsic muscles of the hand are affected
Manifests as “claw hand”
C8-T1

Answer 15

Klumpke Paralysis

Question 16

Deformity do to inability to abduct or opposethe thumb
leaving the thumb resting in adduction, rotated parallel to the plane of the palm
Deformity due to severe median neuropathy
The term clawing refers to the position of the fingers, the term “simian/ape” hand refers to the position of the thumb

Answer 16

“Ape Hand”