Neurovasculature of the upper limb

Question 1

What is the axilla?

Answer 1

Gateway and transition zone between the neck and arm- it is protected by adduction of the upper limb, and formed by the clavicle, scapula, thoracic wall, humerus and associated muscles.

Question 2

What is the axilla made up of?

Answer 2

4 walls, inlet (apex) and floor (base)
Apex- Rib 1, Scapula and clavicle: gives rise to cervicoaxillary canal (pass. between neck and axilla, where aa,vv, ll and nn traverse opening)
Ant. wall- Pec major/minor, subclavius
Med. wall- Thor. wall (R1-4), Serr. ant
Post.wall- subscapularis, ter. maj, lat.dorsi
Lat. wall- intertubercular groove of humerus
Base- skin/fascia

Question 3

Arterial supply of axilla

Answer 3

Subclavian- VITCD
Vertebral, Internal thoracic, Thoracic trunk, Costocervical trunk, Dorsal scapular
Axillary, Brachial, Radial, Ulnar, Superficial/deep palmar arches
Aortic arch- brachiocephalic trunk, left common carotid, left subclavian artery

Question 4

Role and divisions of the axillary artery

Answer 4

Supplies walls of axilla and related regions- continuous w subclavian/brachial AA’s

1. Lateral aspect R1 > medial aspect pec.minor
2. Medial aspect pec. minor > lateral aspect pec. minor
3. Lateral aspect pec minor > inf. border teres major

Branches of each part
1. Superior thoracic
2. Thoracoacromial, Lateral thoracic
3. Subscapular, Ant. circumflex humeral, Post. circumflex humeral
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Question 5

Role of brachial artery

Answer 5

Continuation of axillary artery- main bloody supply for arm

- Gives rise to Profunda Brachii (deep artery) immediately (travels in radial groove of humerus)

Question 6

Venous drainage of the arm

Answer 6

Blood from hand, forearm + arm > heart through superficial and deep veins
Superficial
- Cephalic v
- Basilic v
- Median cubital v

Deep

• Radial vv
• Ulnar vv
• Brachial vv

Question 7

Lymphatic drainage

Answer 7

-Upper limb, most of breast and cutaneous vessels of trunk above level of umbilicus drain to axillary nodes
5 groups- drain to jugular-subclavian venous confluence
1. Lateral (humeral)
2. Anterior (pectoral)
3. Posterior (subscapular)
4. Cervical
5. Apical

Question 8

Nervous supply

Answer 8

BRACHIAL PLEXUS
-formed by union of ANTERIOR rami of C5-C8 and T1 nerves
-Originates from neck, passing laterally + inferiorly over rib 1 and entering axilla
- Roots, Trunks, Divisions, Cords, Branches
All major nerves in UL originate from BP- mainly cords