Axilla And Brachial Plexus Flashcards
What artery/vein are contained in the axilla?
Axillary artery and vein
Subclavian artery becomes axillary artery where?
Axillary artery becomes brachial artery past ___
At the first rib
Teres major
Boundaries of the axilla:
Apex =
Base (inferior) =
Anterior wall=
Posterior wall=
Medial wall =
Apex = borders of clavicle, scapula, and first rib
Base= axillary folds (lower border of pec major and lower border of teres major and lats), thoracic wall
Anterior= pec major/minor and subclavius
Posterior= subscapularis, teres major, lats, scapula
Medial = upper 4-5 ribs, intercostal muscles, serratus anterior
Axillary lymphatics
- Pectoral (anterior) nodes:
- Subscapular (posterior) nodes:
- Humeral (lateral) nodes:
- Lymph vessels from anterior thoracic and abdominal walls, lateral breast
- Lymph vessels from the back
- Lymph vessels from upper limb
- Axillary nerve provides SENSORY innervation for ?
- Radial nerve provides SENSORY innervation for?
- Musculocutaneous nerve provides SENSORY innervation for?
- Median nerve provides SENSORY innervation for?
- Ulnar nerve provides SENSORY innervation for?
- Small area of lateral/proximal arm
- Posterior arm, forearm, and hand
- Lateral forearm
- Lateral hand and fingers (half of ring, middle, pointer, and thumb)
- Medial hand and fingers (half of ring and all of pinky)
What are the subdivisions of all the parts of the brachial plexus:
- Roots
- Trunks
- Divisions
- Cords
- Nerves
- C5-T1
- Superior, middle, inferior
- Anterior/ventral and posterior/dorsal
- Lateral cord, posterior cord, medial cord
- Musculocutaneous, axillary, radial, median, and ulnar
What nerves are supplied by the dorsal division?
Ventral division?
Dorsal = radian and axillary
Ventral = musculocutaneous, median, and ulnar
Four nerves that are short branches of the supraclavicular ?
What muscles do these branches innervate?
Dorsal scapular nerve: levator scap, rhomboid major and minor
Long thoracic nerve: serratus anterior
Subscapular nerve: subscapularis and teres major
Suprascapular nerve: supra/infraspinatus
Axillary nerve motor innervations?
Axillary nerve sensory innervations?
Motor- deltoid and teres minor
Sensory- small area of lateral/proximal arm
Radial nerve motor innervations?
Radial nerve sensory innervations?
Motor- extensors in arm and forearm (no intrinsic hand muscles)
Sensory- posterior arm, forearm, and hand
Pectoral group- what part innervates what muscles?
Lateral and medial pectoral nerve innervate pec major
Medial pectoral nerve innervates pec minor
Sensory and motor innervations of the musculocutaneous nerve
Sensory- lateral forearm
Motor- flexors in arm
Median nerve motor and sensory innervations
Motor - most flexors in forearm, most extrinsic hand flexors, thenar muscles, 1/2 lumbricals
Sensory- lateral hand and fingers
Ulnar nerve motor and sensory innervations?
Motor- 1 1/2 flexor in forearm, all intrinsic hand muscles (except thenar muscles), 1/2 lumbricals
Sensory- medial hand and fingers
Posterior cord is formed by what?
By the posterior divisions of the 3 trunks
Posterior cord branches off to what nerves of the brachial plexus?
Axillary and radial
The lateral cord divides into what nerves?
The musculocutaneous nerve and median nerve (lateral root of median nerve)
Medial cord divides into what nerves?
Ulnar nerve and the median nerve (medial root of median nerve)
Two nerves that branch off of the roots?
What roots do they branch off of?
Dorsal scapular nerve (C5)
Long thoracic nerve (C5-C7)
What nerves arise from the superior trunk?
Suprascapular nerve and nerve to subclavius
No nerves arise from the ?
Divisions
Each cord gives off some nerves
- What nerves do the lateral cord give off?
- Posterior cord?
- Medial cord?
- Lateral pectoral nerve
- Upper middle and lower subscapular nerve (middle aka thoracodorsal nerve)
- Medial pectoral nerve, medial brachial cutaneous nerve, and medial antebrachial cutaneous nerve
Clinical aspects of brachial plexus:
Upper brachial plexus injury occurs from?
What kind of paralysis could this form? Presentation?
Extreme lateral flexion of the head, especially if the shoulder is simultaneously depressed (can also happen during birth)
~ stress on C5/C6 root
Erb-duchenne paralysis: waiters tip position
Lower brachial plexus injury occurs from?
What kind of paralysis? Presentation?
Extreme abduction (if someone was falling off a cliff and reaches up to hold a branch and hang) (can also occur during birth) ~stress on C8/T1
Klumpkes paralysis= claw hand
