Elbow, forearm, wrist

Question 1

Elbow complex

Answer 1

anatomically two articulations

Question 2

Humeroulnar joint is what type?

Answer 2

simple hinge

Question 3

Humeroradial joint is what type?

Answer 3

pivot joint resembling very shallow ball and socket; radius is the socket

Question 4

Humoral ulnar joint movement

Answer 4

-single degree of freedom in sagittal plane
-0-140 degrees flex/ext

Question 5

Forearm motion

Answer 5

-1 degree of freedom
-transverse plane
-involves 3 joints (humeroradial spins, proximal and distal radio-ulnar glide)

Question 6

Which humeral condyle is longer? What does it create?

Answer 6

medial; carrying angle (normal 5-15 degrees)

Question 7

Collateral ligaments: medial vs. lateral

Answer 7

-medial collateral sprains more common than lateral w/ fall onto outstx hand

Question 8

Annular ligament

Answer 8

constrains radial head while allowing spin (band that secures radial head onto ulna)

Question 9

What is a universal concern after elbow trauma/immobilization?

Answer 9

stiffness

Question 10

Compensatory motion for pronation

Answer 10

shoulder abd and IR

Question 11

Compensatory motion for supination

Answer 11

none

Question 12

What to anticipate w/ epicondylar fracture?

Answer 12

flex/ext contractures

Question 13

What to anticipate w/ radial head fracture?

Answer 13

pro/sup hurdles

Question 14

Casting after elbow trauma should bias towards…

Answer 14

flex and sup

Question 15

What insufficiency occurs w/ passive wrist extension

Answer 15

-fist = more extension
-fingers extended = less (flexors are passively insufficient b/c lengthened)

Question 16

Muscles of elbow

Answer 16

-brachialis: inserts into ulna, originates on humerus (pure flexor)
-biceps: inserts into radius; flexor and supinator
-brachioradialis: inserts into distal radius; type III lever w/ elbow in mid range flex
-triceps: extensors

Question 17

Medial mass forearm muscles

Answer 17

pronators, wrist and finger flexors

Question 18

Lateral mass forearm muscles

Answer 18

supinators, wrist and finger extensors

Question 19

Major proximal artery/vein in shoulder complex

Answer 19

axillary

Question 20

Two major mixed nerves proximally

Answer 20

axillary, musculocutaneous

Question 21

3 major nerves distally at elbow (2 ant. and 1 post. to joint axis)

Answer 21

-anterior: radial, median
-posterior: ulnar

Question 22

Where can nerve entrapments occur? What damage can they cause?

Answer 22

-ulnar in cubital tunnel (damage causes claw hand)
-median travels in carpal tunnel, entrapment ant. forearm (damage thumb muscles)
-radial entrapment in fascia(?) damage causes wrist drop

Question 23

Mobility/stability in RA? What deviation?

Answer 23

more mobility, less stability into ulnar deviation

Question 24

Thrower’s elbow

Answer 24

repetitive valgus stress on medial collateral ligament

Question 25

Little League elbow

Answer 25

stress on cartilage growth plate

Question 26

Nursemaid's elbow

Answer 26

dislocate radial head out of annular ligament

Question 27

Active insufficiency

Answer 27

muscles too shortened and no longer has ability to generate effective muscular force

Question 28

Passive insufficiency

Answer 28

muscles too lengthened and no longer has ability to generate optimal muscular force

Question 29

Radial nerve palsy does what to long finger flexors?

Answer 29

active insufficiency

Question 30

Hand rules of 1/2's

Answer 30

thumb is 1/2 and sensation is 1/2 hand function

Question 31

Digit alignment

Answer 31

each finger naturally flexes to center of wrist (lunate; combined flexion is system of stability)

Question 32

Degrees of freedom in MP joint

Answer 32

2; flex/ext, abd/add

Question 33

Degrees of freedom in DIP joint

Answer 33

1; flex/ext

Question 34

Degrees of freedom in C-MC joint

Answer 34

3; flex/ext, abd/add, opposition

Question 35

Ligaments of hand

Answer 35

-collateral ligaments at all articulations -transverse ligaments across heads of finger metacarpals

Question 36

Collateral ligaments in flexion and extension

Answer 36

-flexion = closed pack -extension = loose pack

Question 37

Carpal-metacarpal joint arthrokinematics

Answer 37

-flex/ext: distal concave moving on proximal convex (trapezium convex) -abd/add: distal convex moving on proximal concave (trapezium concave) **think saddle**

Question 38

What is the resting hand position?

Answer 38

30 degree wrist ext, 80 degrees MP flex, full IP ext

Question 39

What are the extrinsic finger muscles?

Answer 39

MP extensors, long finger flexors

Question 40

What are the intrinsic finger muscles?

Answer 40

lumbricals, interossei

Question 41

What are the extrinsic thumb muscles?

Answer 41

FPL, APL, EPL and EPB

Question 42

What are the intrinsic thumb muscles?

Answer 42

thenar eminence (FPL, APB, OP)

Question 43

Grips for power and what muscles

Answer 43

power and hook; extrinsic muscles, long finger flexors

Question 44

Grips for precision and what muscles

Answer 44

pinch/precision grip; intrinsic muscles and thumb