Posterior Compartment/EXtENsors Forearm Flashcards Preview

Anatomy EXAM 1 > Posterior Compartment/EXtENsors Forearm > Flashcards

Flashcards in Posterior Compartment/EXtENsors Forearm Deck (12):

A. All mucles in the Posterior Forearm are innervated by the ____ _____

B. DESCRIBE the extent of this nerve and its branches in the POST-forearm
1. Radial n. proper

2. DEEP Branch Radial n. [3]

A. All POST-forearm muscles are innervated by the RADIAL nerve & its branches

1. Radial n. proper innervates [extensor carpi radials longus] and then SPLITS into superficial cutaneous & DEEP branches

2. DEEP Branch Radial n. innervates [extensor carpi radials brevis] & supinator-->then it pierces supinator to become [POST interosseus nerve]-->which innervates all other extensors


What muscles rotates radius on the ulna (supines forearm)



What muscles EXTEND the HAND @ the wrist and where do they insert? [3]

C: in which direction do each of these muscles actually move the hand? [2 each]
D: Are these muscles Superficial, Deep or BOTH?

E: What nerve innervates these muscles?

1: Extensor carpi radials longus- ABducts & Extends
2:Extensor carpi radials brevis- ABducts & Extends
[lateral away from body] & Extends

3. Extensor carpi Ulnaris- ADDucts & Extends
[medial mvmnt BACK TOWARD BODY] & Extends
B: = -->Carpi Longus inserts 2nd metacarpal / carpi brevis: 3rd metacarpal / Ulnaris EXT: 5th metacarpal
"Superficial Extensors [Bring Cats Directly 2 cdU]"

E: Radial n.


A. What muscles extend wrist & DIGITS? [3]
B. Which digits do they extend each?
C. Where do they insert?

< "Did" extends the DIGITS! >
1-extensor digitorum = digits 2-5

2-extensor indicis = just digit #2
3. extensor digiti minimi= just digit #5

C. inserts into extensor expansions=aponeuroses formed on each digit by extensor and intrinsic muscle tendons


A: Which muscles EXTEND the thumb [3]
B: Where exactly does each extend it
C: Where do they insert?

1-ABductor pollicis longus=extends & ABducts thumb

2-extensor Pollicis brevis=extends Thumb PP(Proximal Phalanx)

3-extensor Pollicis Longus=extends Thumb DP
C: All insert onto bases of 1st metacarpal, PP and DP


1. Name the muscle that can only "weakly" flex the forearm when pronated :-O... why is this?

2. What is this muscles main job?

3. What nerve innervates this muscle?
4. What is its perfusion artery?

1. BRACHIORADIALIS becuz it attaches to
[ humerus supracondylar ridge] & radius

2. Flexion of the Elbow & Forearm Supination/Pronation
3. RADIAL n.

4. Radial recurrent artery


What are the *Superficial* layers of the POST-FOREARM EXTENSOR group [6]

"Superficial Extensors [Bring Cats Directly (2) cdU] "

C=Carpi radialis LONGUS

c=carpi radialis brevis
d=digiti minimi

U=Ulnaris (carpi Ulnaris)


What are the *DEEP* layers of the POST-FOREARM Extensor Group [6]

"DEEP Extensors are usually needed [ASAp Pi] ! "

A=ABductor pollicis LONGUS
p= pollicis brevis

i= indicis


A: What 3 Extensor tendons form the Anatomical snuff box?

B: Which artery is found within this snuff box? Which nerve is found ON TOP this snuff box?

A: Snuff box=
[EX ABdcutor pollicis Longus],
superior = [EX Pollicis Longus tendon]
inferior= [EX Pollicis brevis tendon] inferiorly

B: RADIAL artery is INSIDE snuff boxy while superficial branch Radial n. is ON TOP of snuff box


What nerve is known as the "million dollar" nerve?

The [Median n. recurrent thenar branch]


1. Deep Palmar Fascia is thin in the ____ but THICK in the ______ where it forms the Palmar Aponeurosis

2. What exactly is the Palmar aponeurosis?

1. Deep Palmar Fascia is thin over the thenar/hypothenar eminences but THICK in the palm where it forms Palmar Aponeurosis

2. PA= Dense strong well-defined triangular layer of deep fascia located in middle palm


1. Location
2. Function
3. nerve innervation

Anconeus=tiny Superficial Extensor muscle located behind elbow under EX. Digitorum & Ulnaris

2. Extends forearm
3. All Post-axial forearm muscles = RADIAL n. innervation