Bracial Plexus

Question 1

Name the divisions of the Brachial Plexus

Answer 1

Roots

Trunks

Cords

Divisions

Branches

Question 2

The anterior rami is what section of the brachial plexus?

Answer 2

Roots: C5, C6, C7, C8, & T1

Question 3

Anterior and Posterior Nerve Roots are also called:

1. _________
2. _________

The Posterior contains (a)_______ neurons that carry info TO the CNS?

The Anterior contains (b)______neurons that carry info AWAY from the CNS?

Answer 3

1. Dorsal
2. Ventral

A) Sensory Neurons

B) Motor Neurons

Question 4

WHAT IS THE AXILLA & its contents?

Answer 4

The AXILLA consists of an apex formation with 4 walls and a base.

All of the nerves and vessels of the upper limb pass throught this canal (cervicoaxillary canal)

Question 5

What muscles form the Anterior Wall of the Axilla?

Answer 5

Axilla Anterior Wall

1. Pectoralis Major
2. Pectoralis Minor
3. Subclavius muscle

Question 6

What muscles form the posterior wall of the Apex?

Answer 6

Posterior Wall

1. Subscapularis
2. Teres Major
3. Latissimus Dorsi

Question 7

Subscapularis

O:

I:

A:

N:

Answer 7

Subscapularis (anterior to scapula)

O: Scapular Fossa

I: Lesser Tubercle of Humerus

A: Medial Rotation of GHJ

N: Superior/Inferior Subscapular Nerves

(brachial Plexus: C7; Cords; Posterior [forms radial nerve] )

Question 8

What muscles form the MEDIAL WALL of the Axilla?

Answer 8

Medial Wall-Thoracic Wall

1. Ribs 1-4
2. Serratus Anterior

Question 9

What muscles form the LATERAL WALL of the Axilla?

HINT: Bicipital Groove

Answer 9

Lateral Wall

1. Latissimus Dorsi (attaches to intertubercular groove [Bicipital Groove] )

Question 10

What forms the BASE of the Apex?

Answer 10

Base or Floor of the Apex

1. Skin/facia of the concave axilla (armpit)

Question 11

The AXILLARY ARTERY is divided into what 3 parts by the _______ minor?

Answer 11

AXILLARY ARTERY

Divided into 3 parts by PECTORALIS MINOR

1. Superior Thoracic Artery
2. Two Branches: Thoracoacromial trunk, Lateral Thoracic
3. Three Branches: Subscapular, Anterior Circumfles Humeral, Posterior Circumflex Humeral

Question 12

The Subclavius & Suprascapular Nerves branch off of which trunk?

A) Superior

B) Middle

C) Inferior

Answer 12

Subclavius & Suprascapular Nerves branch off of the

SUPERIOR trunk

(C5/C6 Anterior Rami)

&

Subclavius N. =Subclavius M.

Suprascapular N. = Infraspinatus, Supraspinatus, & GHJ

Question 13

Which division of the Brachial Plexus are FLEXORS, EXTENSORS?

Answer 13

ANTERIOR Division: FLEXORS

POSTERIOR Division: EXTENSORS

Question 14

Brachial Plexus:

What are the 3 divisions of the Cords

Answer 14

Lateral Cord:

Posterior Cord:

Medial Cord:

Question 15

Lateral Cord:

What cervical vertebra do the Lateral Cords originate from?

What Nerve branches directly from the lateral cord?

What Terminal Nerve comes after?

Answer 15

Lateral Cord:

C5/C6/C7 Anterior Rami (flexor & Posterior Extensor);

Lateral Pectoral Nerve branch;

Forms the Musculocutaneous/Median Terminal Branches

Question 16

Posterior Cord:

The Posterior Cord contains what 4 subcords?

Answer 16

Posterior Cord

Superiorly = 1. Axillary N.

Inferiorly = 2. Superior Subscapular N.; Thoracodorsal N.; Inferior Subscapular N.

Question 17

Medial Cord:

The Medial Cord contains what 4 subcords?

Answer 17

Medial Cord:

1. Medial Pectoral
2. Medial Cutaneous (arm)
3. Medial Cutaneous (forearm)