Comparative Anatomy of Upper and Lower Limb

Question 1

Following embryonic limb rotation, what becomes the plantar aspect of the foot?

Answer 1

The ventral (anterior) surface of the developing lower limb

Question 2

Following embryonic limb rotation, where are the ventral flexor muscle masses located?

Answer 2

Largely posterior to the knee, as opposed to anterior to the elbow

Question 3

What allows the grasping hand to be placed into many varied locations?

Answer 3

The prehensile abilities of the upper limb

Question 4

What does the prehensile ability of the upper limb rely on?

Answer 4

The composite mobility of all of the joints involved

Question 5

What must the stability of the lower limb provide?

Answer 5

The ability to balance

Question 6

Where do the only rotational movements of the lower limb occur?

Answer 6

At the hip

Question 7

Where in the lower limb is there no significant movement?

Answer 7

Tibio-fibular joints

Question 8

What are the synovial spaces of the sternoclavicular joint lined by?

Answer 8

Fibrocartilage (rather than hyaline cartilage)

Question 9

What do the synovial spaces of the sternoclavicular joint provide?

Answer 9

Shock-absorbance

Question 10

Where does the costoclavicular ligament run from?

Answer 10

From the first rib to the clavicle

Question 11

What does the orientation of the coracoclavicular ligament provide?

Answer 11

Strength for the acromioclavicular joint

Question 12

What occurs when there is shoulder ligament injury?

Answer 12

There is increased depression of the scapula when load is applied

Question 13

What is the clavicle highly responsible for?

Answer 13

Stability of the pectoral girdle

Question 14

What causes minor rotation of the pelvic bones?

Answer 14

Heavy load applied down through the pelvis, particularly through the base of the lumbar vertebrae

Question 15

The rotation of the pelvic bones would be increased if not for what?

Answer 15

Sacroiliac and sacrospinous ligaments

Question 16

What is the main function of the sacrospinous and sacrotuberous ligaments?

Answer 16

To hold pelvis and sacrum together

Question 17

The pelvis would be stronger with more bone and ligaments, but what would this result in?

Answer 17

More bone would make the pelvis too heavy

More ligaments would compromise movements and structures that need to pass through

Question 18

Why is the femoral triangle not folded against the trunk?

Answer 18

Due to limb rotation and bipedal stance

Question 19

What are the contents of the femoral triangle

Answer 19

A stem artery enters and gives off a deep branch
Accompanying major vein receives a superficial tributary
Nerves

Question 20

What carries almost the entire innervation of the upper limb?

Answer 20

The brachial plexus

Question 21

Where does the brachial plexus enter the axilla?

Answer 21

At the lateral border of the first rib

Question 22

Why is the innervation of the lower limb more complex than that of the upper limb?

Answer 22

Because the lumbosacral plexus lies within the pelvis and 3 different major branches of it enter through separate routes

Question 23

Where does the median nerve enter the palm of the hand?

Answer 23

Via the carpal tunnel

Question 24

Where do the ulna artery and nerve enter the hand?

Answer 24

Superficially

Question 25

Where does the radial artery enter the hand?

Answer 25

Through the first web space

Question 26

Where do the posterior tibial artery and nerve enter the foot?

Answer 26

Posterior to the medial malleolus

Question 27

What does the posterior tibial artery give rise to?

Answer 27

The plantar arch via lateral and medial plantar arteries