Anatomy week 3 Brachial plexuses

Question 1

Where does brachial plexus orginate from

Answer 1

• The anterior(ventral) rami of cranial nerves ( C5-C8) AND T1

Question 2

Where does the brachial plexus pass between

Answer 2

• Anterior and middle scalene muscles

Question 3

Where does the brachial plexus travel behind

Answer 3

• Behind the clavicle

Question 4

Where does the brachial plexus descend into

Answer 4

Axillary region

Question 5

Name the 2 parts that the brachial plexus can be divided into

Answer 5

• Supraclavicular part
  -Infraclavicular part

Question 6

Name the nerves in the anterior division to the anterior compartment

Answer 6

• Musculocutaneous nerve
  -Median nerve
  -Ulnar nerve

Question 7

Name the nerves from the posterior division to the posterior compartment

Answer 7

• Axillary nerve
  -Radial nerve

Question 8

What does these musculocutaneous nerve supply

Answer 8

Arm flexors

Question 9

What does the Median nerve supply

Answer 9

• Supplies the anterior forearm muscles and lateral palm

Question 10

What does the ulnar nerve supply

Answer 10

• Anteromedial forearm and medial hand

Question 11

What does the Axillary nerve supply

Answer 11

Deltoid and teres minor

Question 12

What does the radial nerve supply

Answer 12

• Posterior compatment of the limb

Question 13

What is Klumpke Palsy caused by

Answer 13

Injury to the inferior trunk

Question 14

What are the sympotoms of klumpke Palsy

Answer 14

• Weakness in intrinsic hand muscles
  -Grip weakness
  Sensory loss in ulnar aspect of hand and forearm

Question 15

Where does the radial nerve originate from

Answer 15

• C5 - T1 , posterior cord

Question 16

What is the largest branch of brachial plexus

Answer 16

• Radial nerve

Question 17

What does the radial nerve pass out / through and supply

Answer 17

• Triangular interval
  -Supply triceps brachii

Question 18

What does the radial nerve travel down

Answer 18

Radial groove

Question 19

What does the radial nerve divide into

Answer 19

• Superifical (sensory) branch
  -Deep (Motor) branch

Question 20

Name the movements in relation to the radial nerve

Answer 20

• Extension of elbow,wrist and fingers
  -Forearm supination
  -Thumb abduction

Question 21

Name the injury of the radial nerve

Answer 21

Radial nerve palsy

Question 22

Give symptoms of radial nerve palsy

Answer 22

• Wrist drop
  -Weak grip
  -Radial sensory loss

Question 23

Name the differnet injuries radial nerve palsy

Answer 23

• Saturday night palsy
  -Crutch palsy
  -Humeral fracture
  -Radial head fracture

Question 24

Where does the Axillary nerve originate from

Answer 24

• C5-C6 , from posterior crod

Question 25

Where does the axillary nerve exit through

Answer 25

Quadrangular space

Question 26

What does the radial nerve innervate

Answer 26

Arm and forearm

Question 27

What does the Axillary nerve innervate

Answer 27

- Deltoid and teres minor

Question 28

How can the axillary nerve be injured

Answer 28

- From shoulder dislocation or surgical neck fracture , which wasuses deltoid weakness

Question 29

What does the musculocutaneous nerve originate from

Answer 29

C5- C7, lateral cord

Question 30

What does the musculocutaneous nerve innervate

Answer 30

- Biceps brachii, coracobrachialis and brachialis muscles -Anterolateral skin of the forearm

Question 31

Give an example how the musculocutaneous nerve is likely to be damaged

Answer 31

- Due to a stab wound

Question 32

What does an injury to the musculocutenaous nerve cause

Answer 32

-Weak elbow flexion and supination -Sensory loss on lateral forearm

Question 33

Name the 2 places the median nerve originates from

Answer 33

-Later root from lateral cord C6. C7 - Medial rot from medial cord C8,T1

Question 34

Explain how the Median nevres passes in the arm

Answer 34

- Descends down the arm and passes through the pronator teres heads -Then travels through carpel tunnel

Question 35

What does the median nerve innervate

Answer 35

- All anterior forearm flexors except : -Flexor Carpri ulnaris -Ulnar half of Flexor digitorum profundus + The LOAF hand muscles

Question 36

Name the motor functiosn that the medial nerve allows

Answer 36

- Thumb flexion and opposition -Flexion of digits 2 + 3 -Wrist flexion and abduction -Forearm pronation

Question 37

Name injuries associated with the medial nerve

Answer 37

- Honeymoonrs palsy -Fractures of humerus or distal radius -Carpal tunnel syndrome

Question 38

Where does the ulnar nerve originatge form

Answer 38

C8- T1 , terminal branch of the MEDIAL CORD

Question 39

Explain the course / how the Brachial plexus travels

Answer 39

1 Passes between the anterior and middle scalene muscles 2 Travels behind the clavicle 3 Descends into the Axillary region

Question 40

Explain how the Radial nerve travels / course

Answer 40

- Passes throught the triangular intervals and supplies the triceps brachii - Travels in radial groove humerus - Wraps anteriorly over lateral epicondyle

Question 41

Explain the course /pathways of the axillary nerve

Answer 41

Exits throught the quadrangular space , winds around surgical neck of humerus

Question 42

Explain the course of the Ulnar nerve

Answer 42

-Runs medially down the arm, behind the medial epicondyle → enters anterior forearm via cubital tunnel. Continues medially in the forearm, enters hand via Guyon’s canal

Question 43

What is entrapment

Answer 43

When the nerve becomes compressed

Question 44

In the Cubital tunnel syndrome where is the entrapment site

Answer 44

- Resting elbows on hard surfaces

Question 45

In Guyons Canal syndrome when does entarpment take place

Answer 45

- Prolongued leaning forward while cycling

Question 46

What does the ulnar nerve innervate ( motor)

Answer 46

Forearm: -Flexor carpris ulnaris -Medial half of flexor digitorum profundus Hand: - Most intrinisc muscles excpet LOAF hand muscles

Question 47

What does the ulnar nerve innervate in relation with sensory

Answer 47

- Medial palmar skin -Medial aspect of Dorsum of hand

Question 48

What does damage to the Ulnar nerve lead to

Answer 48

Weak: -wrist flexion and adduction -Finger adduction/abduction -Flexion 4 and 5 th digits

Question 49

Give examples the Long thoracic nerve can be injured

Answer 49

- Knife qounds , mastectomy

Question 50

What muscle is affected when the long Thoracic nerve is damaged

Answer 50

Serratus anterior

Question 50

What is a sign of damage to the long thoracic nerve + serratus anterior

Answer 50

- Winged scapula

Question 50

Where does the Thoracodorsal nerve originate from

Answer 50

- C6-C8 , posterior cord

Question 51

What does the thoracodorsal nerve supply

Answer 51

- Latissimus dorsi

Question 54

What are clinical signs of injury to the median nerve

Answer 54

Ape hand