Brachial plexus

Question 1

The brachial plexus is made by the ventral rami of C__ to T__.

Answer 1

C5 to T1

Question 2

What other rami send contributions to the brachial plexus?

Answer 2

C4 and T2

Question 3

The brachial plexus is formed between what two muscles?

Answer 3

anterior and middle scalene

Question 4

The branches of the brachial plexus can be classified into what two groups?

Answer 4

1. Supra-clavicular

2. Infra-clavicular

Question 5

Where do the supra-clavicular branches arise from?

Answer 5

roots, or the trunks of the plexus

Question 6

Where do the infra-clavicular branches arise from?

Answer 6

cords of the plexus

Question 7

In ___% of the normal population the fibres of the brachial plexus can be in the middle scalene.

Answer 7

30

Question 8

any branch coming from a cord is _______.

Answer 8

infraclavicular

Question 9

What is the most important nerve of the arm?

Answer 9

radial

Question 10

What are two examples of injuries where the brachial plexus could be injured, leading to Erb’s palsy?

Answer 10

1. birth
2. falls
   (when angle between head and shoulder is suddenly increased)

Question 11

What trunk is involved in Erbs palsy?

Answer 11

Upper trunk (C5-C6)

Question 12

What movements are lost in Erb’s palsy?

Answer 12

• Most of the movements of the shoulder
• Flexion of elbow
• Extension of wrist joint

Question 13

What trunk does Klumpkes palsy involve?

Answer 13

lower trunk (C8-T1)

Question 14

What muscles are effected by Klumpkes palsy?

Answer 14

• Flexor muscles of wrist and fingers

- Intrinsic muscles of the hand

Question 15

What type of accident commonly causes Klumpkes palsy?

Answer 15

falling accidents when person tries to hang on to something to avoid falling (angle between arm and trunk)

Question 16

When does the subclavian artery turn into the axillary artery?

Answer 16

At the lateral border of the first rib

Question 17

What are the 3 different parts of the axillary artery?

Answer 17

1. Superior
2. Posterior
3. Inferior

Question 18

What artery supplies the pec major and deltoid muscles?

Answer 18

thoracoacromial

Question 19

What muscle does that lateral thoracic artery supply?

Answer 19

serratus anterior

Question 20

What muscle does the upper and lower subscapular nerve supply?

Answer 20

subscapularis

Question 21

What arterie(s) branch off the superior axillary artery?

Answer 21

superior thoracic

Question 22

What arterie(s) branch off the posterior axillary artery?

Answer 22

1. Thoracoacromial

2. Lateral thoracic

Question 23

What arterie(s) branch off the inferior axillary artery?

Answer 23

1. Subscapular
2. Anterior humeral circumflex
3. Posterior humeral circumflex

Question 24

What are the 5 arteries surrounding the scapula?

Answer 24

1. Branch of transverse cervical
2. Suprascapular
3. Thoracodorsal
4. Dorsalscapular
5. Posterior intercostal aa.