Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Axilla+Brac.Plexus
Anatomy of the Axilla and the Brachial Plexus
| Question | Answer |
|---|---|
| * Name the basic divisons of the arteries of the arm | subclavian artery->axillary artery->brachial artery->radial and ulnar arteries |
| * Pectoralis Major: nerve, action | medial and lateral pectoral nerve; flexes, adducts, and medially rotates the humerus |
| * Pectoralis Minor: nerve, action | medial and lateral pectoral nerves; draws the SCAPULa downward and forward; stabilizes it |
| What two structures does the clavipectoral fascia enclose? | The subclavius and the pectoralis minor muscle |
| What is the costocoracoid membrane? What three structues pierce it? | The tough mebrane between the subclavius and the pectoralis minor; cephalic vein, lateral pectoral nerve, and the thoracocromial artery |
| What are the boundaries of the deltopectoral triangle? | clavicle, deltoid muscle, and the pectoralis major muscle |
| Subclavius: nerve, action | nerve to the subclavius, depresses the lateral end of the clavicle, pulls shoulder anteriorly, stabilizes the clavicle |
| What are the boundaries of the axilla: Apex | Apex: clavicle anterior, scapula posterior, first rib is medial |
| What are the boundaries of the axilla: Base | Base: fascia of the skin of the armpit |
| What are the boundaries of the axilla: Anterior wall | pec minor and pec major; lateral border of the pec major forms the anterior axillary fold |
| What are the boundaries of the axilla: posterior wall | subscapularis, teres major, the latissimus dorsi muscles; the teres major and the latissimus dorsi muscles form the posterior axillary fold |
| What are the boundaries of the axilla: Medial wall | Ribs 1-5; intercostal muscles, serratus anterior |
| What are the boundaries of the axilla: Lateral wall | intertubercular (bicipital) groove of the humerus |
| What vessels and nerves pass through the axila? What encloses them? | The axillary artery and vein, the brachial plexus (they are enclosed by the axillary sheath) |
| Where does the brachial plexus get its nerves from? | Formed by ventral rami of C5-T1, with contributions from T2 and C4 |
| What are the trunks of the brachial plexus? What nerves make up each? | Superior: C5 and C6; middle: C7; Inferior: C8, T1 |
| * * What are the divisions of the brachial plexus? | anterior division (FLEXOR PART) and the posterior division (EXTENSOR PART) |
| * * What are the cords of the brachial plexus? | Posterior: all three posterior divisions of the three trunks; Lateral: anterior divisions of the superior and middle trunks; medial: anterior division of the inferior trunk |
| * * What are the terminal branches for the lateral, medial, and posterior cords of the brachial plexus? | Lateral: musculocutaneous nerve and lateral root of the median nerve; Medial: ulnar nerve and medial root of the median nerve; Posterior: radial and axillary nerves |
| * * What are the supraclavicular branches of the brachial plexus that come off at the root? | Dorsal scapular nerve (C5)--rhomboids and the levator scapulae muscle; long thoracic nerve (C5, C6, C7): serratus anterior muscle |
| * * What does the dorsal scapular nerve innervate? Where does this nerve come from? | Rhomboids and levator scapulae muscle; comes from C5, branching off from one of the roots of the brachial plexus |
| * * What does the long thoracic nerve innervate? Where does this nerve come from? | From C5, C6, C7; |
| * * Where does the nerve to the subclavius come from? What does it supply? | Supplies subclavius muscle; comes from upper trunk at the root level (from C5 and C6) |
| * * Where does the suprascapular nerve come from? What does it supply? | Supplies the supraspinatous and infraspinatous; comes from C5 and C6 from upper trunk |
| What branches are given off by the lateral cord? | The lateral pectoral nerve, the musculocutaenous, and the lateral root of the median nerve |
| What does the lateral pectoral nerve innervate? | The pectoralis major and minor muscles |
| What does the musculocutaenous nerve supply? | Muscles of the anterior arm compartment; ends as the lateral antebrachial cutaneous nerve |
| What are the branches of the medial cord? | Medial pectoral nerve, medal branchial cutaneous nerve, medial antebrachial cutaneous nerve, ulnar nerve, and medial root of the median nerve |
| What are the branches of the posterior cord? | Upper subscapular nerve, thoracodorsal nerve, lower subscapular nerve, axillary nerve, axillary nerve, radial nerve |
| What does the upper subscapular nerve supply? | The subscapular muscle |
| What does the thoracodorsal nerve supply? | The latissimus dorsi muscle |
| What does the lower subscapular nerve supply? | The subscapularis muscle and the teres major muscle |
| What does the axillary nerve supply? | teres minor and deltoid muscles (ends as the upper lateral brachial cutaneous nerve) |
| What does the radial nerve supply? | It is the great extensor nerve of the upper limb |
| What causes Erb-Duchene palsy? | excessive increase in angle between neck and shoulder-->tearing of the nerve roots C5 and C6 |
| What are the symptoms of Erb-Duchene palsy? | upper limb hangs limply, medially rotated by the unapposed action of the pectoralis major muscle; forearm is pronated due to loss of action of the biceps (supination of forearm); loss of sensation along lateral side of the limb; "waiter's tip position" |
| What nerves are affected in an Erb Duchene palsy? | Suprascapular (to supraspinatus and infraspinatus nerves); nerve to the subclavius (to subclavius); musculocutaneous nerve (biceps brachii, brachialis, coracobrachialis); axillary (deltoid, teres minor) |
| What do you get with a lesion of the lower brachial plexus? How could you injure yourself this way? | Klumpe's palsy; excessive abduction of arm (lifting up arm forcibly) |
| What parts of the brachial plexus are injured in Klumpe's palsy? | Tearing of C8 and T1 roots; results in damage to the ulnar nerve, which supplies small muscles of the hand |
| What are the symptoms of a Klumpe's palsy? | Hand has clawed appearance (pinky and ring finger flex, all knuckles extend back); loss of sensation along medial side of arm of the upper limb |
| What spinal nerves supply the long thoracic nerve? | C5, C6, C7 |
| How can you injure the long thoracic nerve? | May be injured by blows or pressure on the posterior triangle of the neck, stab wounds, during mastectomy surgical procedures, or athletic injuries |
| * What muscle does the long thoracic nerve supply? | The serratus anterior muscle |
| What happens when the serratus anterior muscle is paralyzed? | Medial border of the scapula protrudes-->winging of the scapula; also, since the scapula can no longer be fixed to the posterior chest wall, triceps brachii is seriusly weakened; abduction of the arm is impaired (weak up motion of scapula) |
| What causes thoracic outlet syndrome? | Condition involving compression of the brachial plexus nerves, subclavian vessels, or both because of inadequate passageway just above first rib and behind the clavicle |
| What are the symptoms of thoracic outlet syndrome? | Neck, shoulder, and arm pain, numbness or impaired circulation to the extremeties |
| What are the three passageways where the brachial plexus trunks and subclavian vessels are subject to compression or irritation? | * * Interscalene triangle; costoclavicular triangle; subcoracoid space |
| What are the borders of the interscalene triangle? | Anterior scalene, middle scalene, and medial border of the first rib |
| What are the borders of the costoclavicular triangle? | Middle third of clavicle; first rib; upper border of the scapula |
| What are the borders of the subcoracoid space? | Beneath the coracoid process just deep to the pectorialis muscle |
| Where does the axillary artery run through? | Direct continuation of the subclavian artery; extends from the lateral border of the first rib to the inferior border of the teres major muscle |
| How is the axillary artery divided? What are the parts? | divided into three parts by the pectoralis MINOR muscle; first part: above muscles, second: behind, third: below |
| By convention, medial, lateral, and posterior cords of the brachial plexus are named according to their relationship to the middle segment of the ____. | Axillary artery |
| What are the branches of the axillary artery (first part) | superior thoracic artery (for the first two intercostal spaces and the serratus anterior muscle) |
| What are the branches of the axillary artery (second part) | Thoracoacromial trunk: arises beneath the pectoralis minor muscle and passes above the upper border of the pectoralis minor and pierces the clavipectoral fascia-->acromial, deltoid, pectoral, and clavicular branches |
| What are the branches of the third part of the axillary artery? | The subscapular artery, which passes down and back to give off the circumflex scapular artery and the thoracodorsal artery |
| Describe the path of the circumflex scapular artery | passes around the lateral border of the scapula between the scapula and the teres major muscle in the triangular space |
| Describe the path of the thoracodorsal artery | passes down along axilla and is joined by the thoracodorsal nerve; both supply latissimus dorsi muscle |
| Describe the path of the anterior and posterior circumflex humeral artery | Posterior circumflex is larger; pass around surgical neck of the humerus and anastomose with each other; posterior circumflex runs in the quadrangular space with the axillary nerve |
| Describe the path of the axillary vein | direct continuation of the basilic vein as it crosses the lower border of the teres major |
| What are the tributaries to the axillary vein | Venae comitantes of the brachial artery, cephalic vein, and tributaries corresponding to the branches of the axillary artery |
| * * Nerve and action of the trapezius | N: spinal root of the accessory nerve; A: upper fibers elevate the scapula, middle fibers retract the scapula, lower fibers depress the scapula, superior + inferior upwardly rotate the scapula (for abduction) |
| * * Nerve and action of the latissimus dorsi | thoracodorsal nerve; extends adducts and medially rotates the humerus |
| * * Nerve and action of the levator scapulae | N: dorsal scapular nerve and ventral rami of C3, C4; elevates the scapula, tilt the glenoid cavity downward, helps retract the scapula |
| * * Nerve and action of the rhomboid muscles | N: Dorsal scapular artery; A: retract the scapula, rotate the scapula inferiorly |
| * * Nerve and action of the serratus anterior | long thoracic nerve; protracts the scapula, fixes the scapula, rotates the glenoid cavity upward |
| * * Nerve and action of the deltoid muscle | Axillary nerve; anterior fibers: flex and medially rotate the humerus, middle fibers: abduct the humerus; posterior fibers: external and laterally rotate the humerus |
| * * Nerve and action of the supraspinatus | suprascapular nerve; abducts the humerus |
| * * Nerve and action of the infraspinatous | suprascapular nerve; laterally rotates the humerus |
| * * Nerve and action of the teres minor | axillary nerve; laterally rotates the humerus |
| * * Nerve and action of the teres major | Lower scapular nerve; extends, adducts, and medially rotates the humerus |
| * * Nerve and action of the subscapularis | N: upper and lower subscapular nerves; medially rotates the humerus |
| What are the borders of the quadrangular space? | Superior: teres minor; inferior: teres major; medial: long head of the triceps brachii; lateral surgical neck of the humerus |
| What are the contents of the quadrangular space? | Axillary nerve, posterior circumflex humeral artery |
| What are the borders + contents of the triangular space? | Teres minor, teres major, long head of triceps bracchi; circumflex scapular vessels (or their branches) |
| What are the borders of the triangular interval? | Teres major, long head of the triceps brachii, and shaft of the humerus |
| What are the contents of the triangular interval? | Radial nerve, profundal brachii artery |
Created by:
karkis77
Popular Anatomy sets