Brachial plexus branches
“My Aunt Raped My Uncle”:
From lateral to medial:
Brachial plexus organization
“The Castrated Dog Turns Rabid”:
From lateral to medial:
- Terminal branches
Brachial plexus subunits
“Randy Travis Drinks Cold Beer”:
Alternatively: “Read The Damn Cadaver Book!”
Alternatively: “Real Texans Drink Coors Beer”.
Brachial plexus: branches of posterior cord
- Subscapular [upper and lower]
Brachial plexus: numbers of each section
It is the same backwards and forwards:
- 5 Rami
- 3 Trunks
- 2 Divisions
- 3 Cords
- 5 Terminal nerves
Cervical plexus: arrangement of the important nerves
4 compass points: clockwise from north on the right side of neck:
- Great auricular
- Lesser occipital
- Accessory nerve pops out between L and S
- Transverse cervical
Dermatome C6 location
Stick arm out like crucifixion stance. Curl your thumb and forefinger into an “OK” symbol while keeping your other fingers straight.
Your hand should now look like a 6 shape.
So C6 dermatome is your thumb and top of arm (reason for crucifix stance).
Dermatome C7 location
C7gives the finger to heaven (as in middle finger).
Median and ulnar nerves: common features
Each supply 1/2 of flexor digitorum profundus.
Each supplies 2 lumbricals.
Each has a palmar cutaneous nerve that pops off prematurely.
Each supplies an eminence group of muscles [ulnar: hypothenar. median: thenar].
Each enters forearm through two heads [ulnar: heads of flexor carpi ulnaris. median: heads of pronator teres].
Each has no branches in upper arm.
Each makes two fingers claw when cut at wrist.
Each supplies a palmaris [median: palmaris longus. ulnar: palmaris brevis].
Median nerve: hand muscles innervated
“The LOAF muscles”:
- Lumbricals 1 and 2
- Opponens pollicis
- Abductor pollicis brevis
- Flexor pollicis brevis
Alternatively: LLOAF, with 2 L’s, to recall there’s 2 lumbricals.
To remember that these are the Median nerve muscles, think “Meat LOAF“.
Median nerve: recognizing it in an opened axilla
The Median nerve is the Middle of a giant capital “M” formed by the musculocutaneous and ulnar nerves.
Pectoral nerves: path of lateral vs. medial
“Lateral Less, Medial More”:
Lateral pectoral nerve only goes through Pectoralis major, but
Medial pectoral nerve goes though both Pectoralis major and minor.
Radial nerve: muscles innervated
“Try A Big Chocolate Chip Sundae, Double Dip Cherries And Peanuts Preferably Included”:
In order of their innervation, proximal to distal:
- ext. Carpi radialis longus
- ext. Carpi radialis brevis
- ext. Digitorum
- ext.Digiti minimi
- ext. Carpi ulnaris
- Abductor poll. longus
- ext. Poll. brevis
- ext. P poll. longus
- ext. Indicis
For the neighboring words that start with the same letter (eg: chocolate and chip), notice that the longer word in the mnemonic, corresponds to the longer of the two muscle names (ex: ext. carpi radialis longus and ext. carpi radialis brevis)
Radial nerve: muscles supplied (simplified)
Hand: nerve lesions
Median nerve=Ape hand (or Apostol [preacher] hand)
Arm fractures: nerves affected by humerus fracture location
From superior to inferior:
- Axillary: head of humerus
- Radial: mid shaft
- Median: supracondular
You can suggest more mnemonics …
Dr. Indrajit Rana