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Flashcards in Forearm Deck (38):
1

radius
-head location
-articulates with
-other important landmarks

head located proximally in discoid shaped
articulates with capitulum and radial notch of ulna
neck
radial tuberosity
medial facing sharpened edge on body
-attachment of interosseus membrane
anterior and posterior oblique lines
ulnar notch; distal radioulnar joint
styloid process; articulation with carpal bones
dorsal tubercle

2

ulna
-important landmarks

olecranon
coronoid process
-lateral side has a radial notch
-supinator fossa and supinator crest
-tuberosity on anterior surface for insertion of brachialis
trochlear notch
lateral sharpened interosseus border
head (distal)
-styloid process
-convex articular surface laterally for articulation with radius

3

functions of pronator quadratus and pronator teres in pronation

quadratus
-prime mover
-responsible for initiation
-can act as only pronator during slow unopposed pronation
teres
-increases strength and speed of pronation

4

radial and ulnar deviation of the hand and wrist require...

pair of muscles
radial deviation
-flexor carpi radialis
-extensor carpi radialis longus
-extensor carpi radialis brevis
ulnar deviation
-flexor carpi ulnaris
-extensor carpi ulnaris

5

lateral epicondyle relation to muscles

common extensor origin of a large number of superficial muscles of posterior surface of forearm

6

primary movers of supination

biceps brachii is a strong supinator used in forceful movements
supinator is prime mover in non-forceful situations

7

interosseus membrane
-function

anchors the radius ulna together
serves as an origin for some of the muscles of the forearm

8

relative strength of radius and ulna's articulation with humerus
-why is one stronger?

ulna has stronger articulation
-olecranon
-coronoid process
-trochlear notch
-all 3 form a strong hinge-type joint
radius
-articulation with capitulum is only anchored by annular ring surrounding head of radius

9

distal articulation of forearm
-formed by

radius articulating with
-scaphoid
-lunate
-maybe triquetral and triquetrum

10

styloid processes (radius and ulna) length comparison

radius styloid process extends more distally

11

colles fracture
-what is it?
-most common mechanism of injury (MOI)
-how will it present?
-what else may be damaged

what
-fracture of styloid process of radius
-displacement of styloid process proximally
MOI
-falling on outstretched hand (forearm extended)
presentation
-styloid processes at same level
may also damage scaphoid bone

12

ulnar nerve
-path at the distal humerus
-level of protection

swings around the medial epicondyle of the humerus
relative unprotected

13

nerves of the forearm

median
ulnar
radial

14

median nerve
-function

innervates all muscles of the anterior (flexor) compartment except
-brachioradialis
-flexor carpi ulmaris
-medial part of flexor digitorum profundus
carries sensory components to the skin of the forearm, hand, elbow, and wrist joints

15

brachioradialis
-innervation
-functions
-usually listed as occupying what compartment
--why?

radial nerve
flexor of forearm at the elbow
usually listed as occupying the posterior compartment of the forearm
-due to origin near the common origin of the extensors of the forearm

16

flexor carpi ulnaris and medial part of flexor digitorum profundus
-innervation

ulnar nerve

17

anterior interosseus nerve
-what is it?
-function

what
-named muscular branch of the median nerve
-arises near apex of cubital fossa
-courses along anterior surface of the interosseus membrane
innervates
-other 1/2 of flexor digitorum profundus (digits 2, 3)
-flexor pollicis longus
-pronator quadratus

18

palmar cutaneous branch of median nerve

articular branches of the wrist

19

ulnar nerve
-location from elbow to wrist

posterior to medial epicondyle
deep to flexor carpi ulnaris along flexor digitorum profundus
medial to ulnar artery

20

ulnar nerve function

articular branches to elbow
muscular branches to
-flexor carpi ulnaris
-flexor digitorum profundus
palmar cutaneous branch to
-medial 1/2 of palmar surface of hand (little and ring finger)
dorsal cutaneous branch to
-medial 1/2 of dorsal surface of hand (little and ring finger)

21

radial nerve
-enters forearm...
-branches into...

enters on
-anterior side of lateral epicondyle between brachialis and brachioradialis
branches into superficial and deep branch

22

radial nerve superficial branch
-function

entirely cutaneous
skin of
-dorsum of wrist
-hand
-thumb
-dorsum of digits 2,3

23

radial nerve deep branch
-function
-location

entirely muscular and articular
innervates
-supinator
-extensor carpi radialis brevis
sweeps around lateral side of radius to extensor compartment

24

posterior interosseus nerve of radial nerve
-function
-location

innervates
-muscles of the deep extensor compartment
travels with posterior interosseus artery (branch of ulnar artery)

25

arteries of the forearm
-names
-derived from

names
-radial
-ulnar
derived from radial and ulnar branches of brachial artery
brachial artery divides in cubital fossa

26

radial artery
-location
-branches

location
-direct line continuation of brachial artery
-extends distally in the anterior compartment to styloid process of radius
-then swings dorsally through anatomical snuff box
branches
-radial recurrent artery
-superficial palmar branch of thenar eminence (thumb)
-carpal branches

27

radial recurrent artery
-part of...

anastomosis of the elbow (cubital anastomosis)

28

ulnar artery
-location
-function

location
-sweeps medially after branching from brachial artery
-lies on FDP, lateral to ulnar nerve
supplies
-medial muscles of hand and forearm
-common flexor synovial sheaths
-ulnar nerve

29

ulnar artery
-branches

anterior and posterior ulnar recurrent arteries (anastomosis of elbow)
common interosseus
superficial and deep palmar arches

30

common interosseus artery off ulnar artery
-branches into

anterior and posterior interosseus arteries

31

anterior interosseus artery
-location

passes distally and then pierces interosseus membrane to join carpal arteries

32

posterior interosseus artery
-location
-branches

passes through interosseus membrane to reach the extensor compartment of forearm
usually located deep to pronator teres muscle belly
branches
-muscular branches
-dorsal and palmar carpal arches

33

anatomical snuff box
-bounded by
-what passes through it?

boundaries
-anterior
--abductor pollicis longus tendon
--extensor pollicis brevis tendon
-posterior
--extensor pollicis longus tendon
radial artery passes deep in this region as it travels from anterior compartment of the forearm to the posterior compartment

34

carpal tunnel
-what is it (broad definition)

flexor retinaculum closing over the carpal groove or sulcus

35

carpal tunnel
-contents

median nerve
tendons of
-FDS
-FDP
-FPL

36

flexor carpi radialis (in relation to carpal tunnel)
-encased in _____ to _____

encased in "Y" shaped attachment of flexor retinaculum to scaphoid and trapezium
does not lie in carpal tunnel

37

compression of the median nerve and difficulty flexing (painful, weak) the digits and wrist can be a result of what?

space occupying lesions
-swelling
-edema
-inflammation of the synovial sheaths

38

what is one method of releasing pressure in the carpal tunnel
-consequences

cut the flexor retinaculum
flexor retinaculum scars over with a corresponding release in pressure and increase in size of carpal tunnel