Primer 22 - The Brachial Plexus Flashcards
Which are the muscles in the posterior wall of the axilla?
Subscapularis muscle, theres major, latissimus dorsi.
Serratus anterior, 1st-4th ribs and the associated intercostal muscles belong to
Medial wall of the axilla
What part of the humerus forms the lateral wall of the axilla?
Interrupter ulnar groove of the humerus
Which are the parts of the anterior wall of the axilla?
Pectoralis major, pectoralis minor
What is the cervicoaxillary canal?
Border by the first rib, the clavicle and the superior border of the scapula, it’s filled by the nerves and blood vessels running from between the neck and the upper extremity.
Which structure have to cross the subclavian artery and vein to change its name to Axillary artery?
They have to cross the inferior border of the First Rib.
What is the name of the Axillary artery after cross the inferior border of the Teres major muscle?
Brachial artery.
Which is the muscle it’s crossed by the Axillary artery when this one is divided?
Pectoralis minor.
Which is located the first branch from the axilla artery ?
The Superior Thoracic Artery is between the Inferior border of the first rib and the medial border of the pectoralis minor, minor contribution to supply the breast.
Which are the branches from thoracoacromial artery?
Clavicular, Acromial, Deltoid and Pectoral branches.
Which are the branches of the Axillary artery that is originated from the deep part of the pectoralis minor muscle?
1)Thoracoacromial artery. 2)Lateral thoracic artery.
Which structures are supplied by Lateral thoracic artery?
Supply blood to the serratos anterior to the pectoral muscles on the anterior wall of the axilla and the subscapularis on the posterior wall of the axilla, also supplies another part of the breast.
Which branch of the Thoracoacromial artery supplies the pectoralis muscles and the breast?
Pectoral branch.
Which branch of the Thoracoacromial artery supplies the deltoid and the anastomoses network over the Acromion?
Acromial branch.
Which branch of the Thoracoacromial artery supplies the esternoclavicular joint and the subclavian muscle?
Clavicular branch.
Which branch of the Thoracoacromial artery supplies the pectoral muscles and the deltoid ?
Deltoid Branch.
Where is the third part of the Axillary artery?
It is between the lateral border of the pectoralis minor and the inferior border of the Teres major.
Which are the 3 branches that comes from the third part of the Axillary artery?
1)Anterior circumflex humeral artery. 2)Posterior circumflex humeral artery. 3) Subscapular artery.
Which are the branches comes from Subscapular artery ?
It descent thru the axilla and bifurcate in to the circumflex scapular artery and the thoracodorsal artery.
What is the pathway follows the circumflex scapular artery?
It travels posteriorly and join to anastomotic networks surrounding the scapula
What is the pathway follows the thoracodorsal artery?
It continues inferiorly and supplies the Subscapularis, the serratus anterior, and some intercostal muscles.
Which arteries conform the anastomotic ring around the surgical neck of the humerus?
Anterior circumflex humeral artery and Posterior circumflex humeral artery.
Which muscles are supplied by the branches of the anastomotic ring around the surgical neck of the humerus?
Deltoid. Teres major and minor. Triceps brachial
Which are the branches from the subclavian artery?
1)Dorsal scapular artery.
2)Suprascapular artery.
They form an anastomotic around the scapula with the circumflex scapular artery.
What will happen If the Axillary artery is ligated distal to the Subscapular artery?
The blood will be unavailable to reach brachial artery and the arm will be come ischemic
Which is the first place of metastasis that you wait in a patient with breast cancer?
Axillary nodes
What is the Sentinal lymph node biopsy?
Injection of Blue dye into the tissue nearly the tumor, at a moment, when you opened the axilla, you look for a blue dye and whatever lymph first shows evidence of the dye we called the node as a sentinel node, you have to take off that node and send to the pathologist and look for evidence of cancer.
What happen in a patient with breast cancer who her sentinel node is not cancer?
You assume that is no cancer in any of the Axillary nodes, so you don’t have to remove anymore nodes.
What happen in a patient with breast cancer who her sentinel node shows cancer?
You have to remove all of the Axillary nodes and look for cancer.
What is lymphedema?
When the lymphatic drain of the arm is obstructive, it is the collection lymph in the subcutaneous tissue, nonpitting edema.
What is the common side effect that can occur after removing the Axillary lymph nods?
Lymphedema of the arm
Which are the roots of the brachial plexus ?
C5, C6, C7, C8 and T1
What are the branches of the brachial plexus?
[Real Texans Drink Cold Beer] Roots(5)-Trunks(3)-Divisions(6)-Cords(3)-Terminal branches(5).
From where comes from the Ulnar’s fibers?
They come from C8 and T1
Which roots form superior trunk?
C5 and C6
Which roots form middle trunk?
Only C7
Which roots form inferior trunk?
C8 and T1
What is the pathway that long thoracic nerve follows?
Travels inferiorly with the lateral thoracic artery at the lateral thoracic wall and innervates the anteriors muscles.
Which nerves are originated from the roots ?
Dorsal scapular nerve(C5). Long thoracic nerve(C5,C6 and C7). To scalene muscles and longus colli (C5,C6,C7 and C8).
Which nerves are originated from the Trunks?
Only two, Nerve to subclavius muscle and Suprascapular nerve.
What it is form when the divisions pass from the neck to the axilla?
Cords (lateral, posterior and medial).
Which divisions form the lateral cord?
The anterior divisions of the upper and middle trunks form the Lateral cord of the brachial plexus.
Which divisions form the medial cord?
The anterior divisions of the inferior trunk form the medial cord
Which divisions form the posterior cord?
The posterior divisions from the upper, medial and inferior trunks combined to form the posterior cord of the brachial plexus.
What is the Axillary sheath?
Which is an extension of the fascia of the neck.
Where are the cords and branches anatomically?
Inferclavicular portion of the brachial plexus
Where are the cords?
Relative to the Axillary artery, around like is the Lateral cord is lateral to the Axillary artery, the medial cord is medial to the Axillary artery and the posterior cord is posterior to the Axillary artery.
Which fibers belong to musculo cutaneous and lateral pectoral nerve ?
They carry fibers from C5, C6 and C7.
Lateral cord and medial cord come from ?
Medial nerve
Which nerves are originated from medial cord?
Medial pectoral nerve. Medial brachial cutaneous nerve. Medial antebrachial cutaneous nerve
What spinal nerves does the Ulnar nerve carry?
Carries fiber from C7,C8 and T1.
What are the branches for the posterior cord?
[ULTRA] (Upper and Lower subscapular nerve, Thoracodorsal nerve, Radio nerve, Axillary nerve).
Which cords form the Radial nerve?
Lateral and medial cords.
Which are the 5 terminal branches from the brachial plexus?
[MARMU] Musculocutaneous, Axillary, Radio, Median and Ulnar.
What type of palsy is caused by an injury to the superior part of the brachial plexus, and what is the associated clinical picture?
Erb-Duchenne Palsy, most common during delivery the baby, shoulder dystocia and the result is injury to the C5 to the C6 spinal nerves. Clinical: weakens in the deltoids muscles the biceps. Clinical picture: shoulder-adduction. Arm-medially rotated. Elbow-extension.
What type of palsy is cause by injury into the inferior part of the brachial plexus and what is the associated clinical picture?
Klumpke palsy, affected C8-T1, median and ulnar nerve that their function is flex the Lumbricals. Clinical picture: claw hand extension of the metacarpophalanges joints and flexion of the interphalages joints
What are the 6 branches of the Axillary artery?
1)Superior thoracic artery. 2)Thoracoacromial artery. 3)Lateral thoracic artery. 4)Anterior circumflex humeral artery. 5)Posterior circumflex humeral artery. 6)Subscapular artery.
What are the branches of the Subscapular artery?
1)circumflex scapular artery. 2)Thoracodorsal artery.
What are the 3 branches of the lateral cord of the brachial plexus?
1)Lateral pectoral nerve. 2)Musculocutaneous nerve. 3)Median nerve.
What are the 5 branches of the medial cord of the brachial plexus?
1)Median nerve. 2)Ulnar nerve. 3)Medial pectoral nerve. 4)Medial brachial cutaneous nerve. 5)Medial antebrachial cutaneous nerve.
What are the 5 branches of the posterior cord of the brachial plexus?
1)Upper Subscapular nerve. 2)Lower Subscapular nerve. 3)Thoracodorsal nerve(C6-C8). 4)Radial nerve. 5)Axillary nerve.
