Brachial plexus

Question 1

What is the brachial plexus?

Answer 1

The network of nerves and vessels to the arm.

Question 2

What vertebraes supply the arm?

Answer 2

C5, C6, C7, C8 and T1.

5 nerve routes supply the arms muscle and sensation

Question 3

What order are the nerves in?

Answer 3

Roots - Trunks - Divisions - Cords - Branches

Randy - Travis - Drinks - Cold - Beer

Question 4

Name the parts of the trunk?

Answer 4

Superior, middle, inferior

Question 5

Name the different divisions?

Answer 5

Anterior and posterior (divisions of the trunk)

Question 6

Name the parts of the cords?

Answer 6

Lateral, posterior, medial

Question 7

Name the parts of the branches?

Answer 7

Peripheral nerves -> radial, median, ulnar, axillary, musculocutaneous

Question 8

Can you draw the nerve root to the muscles?

Answer 8

Give it a go!!

Question 9

Where does the long thoracic nerve emerge from?

What does it do?

Answer 9

C5 - C7 (5, 6, 7, wings to heaven)

Function = Abducts the scapula. (serratus anterior)
Injury = winged scapula

Question 10

Where does musculocutaneous nerve emerge from?

What does it do?

Answer 10

C5, 6 and 7!!
Enters anterior arm, exits lateral forearm.

Function = shoulder flexion, supination, elbow flexion
(biceps, brachialis)

Question 11

Where does the axillary nerve emerge from?

What does it do?

Answer 11

C5 and C6!!
Posterior to neck of humerus.

Function = shoulder flexion and abduction, weak external rotation. Sensation is lateral upper arm.
(deltoid, teres minor, triceps)
Injury = flat shoulder

Question 12

Where does the median nerve emerge from?

Functions?

Answer 12

C6, C7, C8 and T1!!
Anterior to elbow, between pronator teres.

Function = sensory in palmar thumb, 2nd, 3rd and half of 4th. Dorsal is tips of thumb, 2nd and 3rd.
Injury = carpal tunnel syndrome.

Question 13

Where does the radial nerve emerge?

Function?

Answer 13

C5, C6, C7, C8 and T1!!
Radial groove in humerus.

Function = sensory in back of lateral part of hand but not the tips, also, back or arm and forearm.
Injury = nerve compression in armpit, no extension of wrist.

Question 14

Where does the ulnar nerve emerge?

Function?

Answer 14

C8 and T1!!
Posterior to medial epicondyle (knobbly elbow bit), superficial to FR of wrist.

Function = Medial flexors of wrist, 3rd and 4th lumbricals, muscles of hypothenar eminence. Sensation in little finger and half of 4th (both sides).

Injury = paralyzed muscles, claw hand.

Question 15

How can an OT help?

Answer 15

Always think of impact on function!!

And thus the impact on the clients life skills and occupations.

Question 16

Key movements of each nerve?

Answer 16

Musculo - flexion of elbow

Axillary - gleno-humeral joint movement

Radial - extension of elbow, wrist, fingers, thumb

Median - pronation of forearm, flexion of wrist

Ulnar - Fine movements of fingers

Question 17

How can BP be damaged?

Answer 17

• Fracture of first rib
• Fracture of clavicle
• Fraction injury to neck
• Dislocation of shoulder
• Trauma at birth

Question 18

What happens in nerves damaged at birth?

Answer 18

Erb’s palsy!!

Altered sensation, altered muscle action, altered posture.
Myotomes - muscle groups controlled singularly, e.g. C5 is abduction of the arm.
Dermatomes are same but sensory regions, e.g. C6 is pad of the thumb.