Anatomy Dissection 4 - Poplitea foss and posterior leg (muscles in separate FCs)

Question 1

What are the muscles that bound the popliteal fossa and what border do they bound?

Answer 1

Semitendinosus/ semimembranosus (superomedially)
Biceps femoris (superolaterally)
Medial and lateral heads of gastrocnemius (inferiorly)

Question 2

Describe the venous drainage of the leg starting at the external iliac vein?

Answer 2

External iliac vein splits into the great saphenous vein and the femoral vein
After the adductor hiatus, the femoral vein is known as the popliteal vein
Popliteal vein continues as the posterior tibial vein
Small saphenous vein branches from popliteal vein

Question 3

How does the small saphenous vein end in the popliteal fossa?

Answer 3

By passing through the deep fascia (popliteal fascia) in the median plain of the limb to drain into the popliteal vein

Question 4

Contents of the neurovascular bundle of the popliteal fossa?

Answer 4

In the median plane from superficial to deep:
Tibial nerve
Popliteal vein
Popliteal artery
Popliteal lymph nodes are located along the popliteal vein in the fossa

Question 5

What does the sciatic nerve divide into and where does this occur?

Answer 5

Tibial nerve and common fibular nerve
Superior apex of the fossa (if the division has not already taken place within the gluteal region or posterior compartment of the thigh)

Question 6

If the sciatic nerve has already divided, where are the tibial nerve and common fibular nerve located in the popliteal fossa?

Answer 6

Tibial nerve = descends vertically in the fossa
Common fibular nerve = skirts the lateral border of the fossa deep to biceps femoris tendon leaving the fossa between the tendon and the lateral head of gastrocnemius to reach the fibular neck, which it winds around prior to dividing into deep and superficial fibular nerves

Question 7

What does the sural nerve supply?

Answer 7

Skin and fascia on the posterolateral aspect of the leg and foot

Question 8

how is the sural nerve formed?

Answer 8

The tibial and common fibular nerves each give rise to a sural cutaneous nerve
These cutaneous nerves frequently communicate with each other (the sural communicating branches)
The medial sural cutaneous nerve and the branches in the communicating branch combine to form the rural nerve

Question 9

Name of the sural cutaneous nerve from the tibial nerve?

Answer 9

Medial sural cutaneous nevre

Question 10

Name of the sural cutaneous nerve from the common fibular nerve?

Answer 10

Lateral sural cutaneous nerve

Question 11

Where is the sural nerve located once it leaves the popliteal fossa?

Answer 11

Descends alongside the small saphenous vein in the superficial fascia of the median place of the posterior aspect of the leg

Question 12

What type of injury is the common fibular nerve vulnerable to?

Answer 12

Compression injury against the neck of the fibula e.g. a tight plaster cast (can also be damaged by fractures of the fibular neck)

Question 13

What will aid the examination of the popliteal pulse?

Answer 13

Flexion of the knee to approximately 30 degrees and relaxation of the hamstring muscles

Question 14

What is the order (from anterior to posterior) that the structures leave the posterior compartment of the leg to reach the sole of the foot by passing posterior to the medial malleolus and deep to the flexor retinaculum?

Answer 14

tendon of Tibialis posterior
tendon of flexor Digitorium longus
posterior tibial Artery
tibial Nerve
tendon of flexor Hallucis longus
(Tom Dick ANd Harry)

Question 15

What are the names of the 2 heads and 2 muscle bellies of gastrocnemius?

Answer 15

Medial and lateral

Question 16

What position should the patient’s lower limb be in to perform the ankle jerk deep tendon reflex?

Answer 16

Supine patient with lower limb externally rotated, their knee flexes and their ankle dorsiflexed with gastrocnemius and soleus relaxed

Question 17

Where is struck during the ankle jerk reflex?

Answer 17

Calcaneal tendon just proximal to its insertion into the calcaneus

Question 18

What is the normal response to the ankle jerk reflex test?

Answer 18

Involuntary contraction of the gastrocnemius and solus with the ankle slightly plantar flexing

Question 19

What does a positive ankle jerk test confirm?

Answer 19

Function of:

• the muscles
• their peripheral nerve supply (tibial nerve)
• central connections at spinal cord level (reflex arc)
• central connection above (descending controls which normally act to prevent unwanted recurrent reflexes for occurring during normal functioning)

Question 20

Arterial supply of the leg starting at external iliac?

Answer 20

External iliac divides into profound femoris and femoral artery
Femoral artery continues as popliteal artery
Popliteal artery divides into anterior and posterior tibial artery
Fibular artery branches from posterior tibial artery
After the ankle the posterior tibial artery divides into the lateral plantar and medial plantar artery
The lateral plantar artery continues as the plantar arch
After the ankle, the arterial tibial artery branches into the dorsalis pedis an arcuate artery

Question 21

Where does the popliteal artery divide into the anterior and poser tibial arteries?

Answer 21

Immediately distal to the popliteal fossa

Question 22

What artery supplies the anterior compartment of the leg?

Answer 22

The anterior tibial artery (passes through the interosseous membrane)

Question 23

What artery supplies the posterior compartment of the leg?

Answer 23

The posterior tibial artery

Question 24

Where does the posterior tibial artery run?

How does it leave the posterior compartment?

Answer 24

With the tibial nerve, mainly between the superficial and deep muscles
Passes posterior to the medial malleolus

Question 25

How does the posterior tibial artery terminate in the foot?

Answer 25

By dividing into the medial and lateral planter arteries

Question 26

Where approximately does the fibular artery branch from the posterior tibial artery?

Answer 26

In the proximal half of the compartment

Question 27

Course of the posterior tibial artery?

Answer 27

Descends in the compartment on the posterior inter muscular septum and send perforating branches through the septum to supply the lateral compartment of the leg

Question 28

Blood supply to the lateral compartment of the leg?

Answer 28

Fibular artery

Question 29

What muscle groups does the sciatic nerve supply (via its divisions)?

Answer 29

Posterior compartment of the thigh
Muscles in all compartments of the leg
Intrinsic muscles of the foot

Question 30

Contents of the popliteal fossa?

Answer 30

Tibial nerve and branches
Common fibular nerve
Popliteal artery, vein and lymph nodes
Plantaris
Popliteus