Posterior Arm and Anterior Forearm

Question 1

What does it mean to say that a muscle of the hand is “extrinsic”?

Answer 1

It means that its muscle belly is in the forearm and not the hand

Question 2

Answer 2

Question 3

• A fracture at the surgical neck of the humerus would likely result in damage to the […] nerve and […] artery
• A fracture at the midshaft of the humerus would likely result in damage to the […] nerve and […] artery
• A supracondylar fracture of the humerus would likely result in damage to the […] nerve and […] artery
• A fracture of the medial epicondyle of the humerus would likely result in damage to the […] nerve and […] artery

Answer 3

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6

Question 7

Answer 7

Question 8

Answer 8

Question 9

Answer 9

Question 10

Answer 10

Question 11

Answer 11

Question 12

Explain what this image is showing.

Answer 12

This is showing various places where the scaphoid bone in the hand can fracture. Depending on where the fracture occurs, there is a variable likelihood of healing due to the fact that the blood supply for the scaphoid is mostly in the more distal part of the bone and has to travel in a retrograde fashion from the distal part of the bone to the proximal part. As such, fractures in the distal part have a poor chance of healing due to potential damage to the vasculature. Fractures in the middle portion of the scaphoid have a 70% chance of healing due to the blood supply being intact. Fractures in the more proximal part of the scaphoid have a poor chance of healing.

Question 13

Answer 13

Question 14

Answer 14

Question 15

Answer 15

Question 16

Answer 16

Question 17

Answer 17

Question 18

Answer 18

Question 19

Answer 19

Question 20

Answer 20

Question 21

Answer 21

Question 22

Answer 22

Question 23

Answer 23

Question 24

All the deep muscles of the hand (FDP, FPL, PQ) are innervated by the […], which is a branch of the median nerve.

Answer 24

Anterior interosseous nerve

Question 25

We have more control over the extrinsic hand muscles than we do over the intrinsic hand muscles.

True/False.

Answer 25

False - other way around

Question 26

All intrinsic hand muscles are innervated by either the […] or the […] nerve and all are represented by spinal segments […] through […]

Answer 26

Median

Ulnar

C8

T1

Question 27

Answer 27

Question 28

Answer 28

Question 29

Answer 29

Question 30

Answer 30

Question 31

Answer 31

Question 32

Answer 32

Question 33

Answer 33

Question 34

Answer 34

Question 35

Answer 35

Question 36

This photo shows paralysis of FPL and FDP on the left and just FDP on the right. What nerve is impacted in both of these cases?

Answer 36

Anterior interosseous nerve (part of median nerve)

Question 37

What is this image testing?

Answer 37

Peripheral nerve injury

You would instruct the person to make a fist and then make “jazz hands”

Question 38

Paralysis in this area of the hand would indicate damage to what nerve?

Answer 38

The radial nerve

Question 39

Paralysis in this area of the hand would indicate damage to what nerve?

Answer 39

Ulnar nerve