Popliteal Fossa, Vessels and Nerves of the leg and dorsum of the foot

Question 1

What are the boundaries of the popliteal fossa?

Answer 1

Superolateral - tendon of biceps femoris

Superomedial - semimembranosus (mostly) and semitendinosus tendon

Inferolateral - lateral head of gastrocnemius

Inferomedial - medial head of the gastrocnemius

Roof - popliteal fascia of fascia lata

Floor: posterior surface of the capsule of the knee and the politeus muscle

Question 2

What are the contents of the politeal fossa (7)

Answer 2

1. Termination of the posterior femoral cutaneous nerve
2. Division of the sciatic nerve into its tibial and common fibular components
3. muscular and cutaneous branches of the tibial nerve
4. Cutaneous branches of the common fibular nerve
5. popliteal vein and its tributaries
6. Popliteal artery and its branches
7. popliteal lymph nodes, lymphatic vessels and fat

Question 3

Describe how the contents of the popliteal fossa are packaged

Answer 3

Surrounded by ample amount of fat, from superficial to deep one finds…

Nerves

Veins

Arteries

Question 4

Describe the popliteal artery

Answer 4

Direct continuation of the femoral artery after it emerges from the adductor hiatus. It is the deepest of the vascular structures in the popliteal fossa, lying against the capsule of the knees and the surface of the popliteus muscle. It terminates at the inferior border of the popliteus muscle by dividing into the anterior and posterior tibial arteries.

Question 5

What are the branches of the popliteal artery?

Answer 5

1. Lateral and medial superior genicular aa
2. lateral and medial inferior genicular aa
3. middle genicular a
4. sural branches
5. anterior tibial a
6. posterior tibial a

Question 6

Describe the lateral and medial superior genicular aa

Answer 6

Located deep to hamstring musculatur, pass in their respective directions superior to the heads of the gastrocnemius muscle to participate in the genicular anastamosis

Question 7

Describe the lateral and medial inferior genicula aa

Answer 7

located deep to the heads of the gastrocnemius muscle, pass in their respective directions on or near the superior surface of the popliteus muscle to participate in the genicular anastamosis

Question 8

Describe the middle genicular a.

Answer 8

Arises from the anterior surface of the popliteal a. passes through the capsule of the knee to supply the interior of the knee joint

Question 9

Describe the sural branches of the popliteal a.

Answer 9

two of them, pass directly into the lateral and medial heads of the gastrocnemius muscle.

Question 10

What are the branches of the anterior tibial a.?

Answer 10

Posterior

1. Posterior tibial recurrant a.
2. circumflex fibular a.

Anterior

1. Anterior tibial recurrent a.
2. medial and lateral malleolar branches
3. dorsalis pedis a.

Question 11

Describe the dorsalis pedis a.

Answer 11

• Terminal branch of the anterior tibial a. as it passes inferior to the superior extensor retinaculum
• courses along the medial dorsum of the foot to provide the following branches

1. lateral and medial tarsal a.
2. arcuate a.
3. first dorsal metatarsal a.
4. deep plantar a.

Question 12

Describe the posterior tibial a.

Answer 12

• One of two terminal branches of the popliteal artery, courses inferiorly deep to the soleus occupying a central position in the leg. Passes behind the medial malleolus between the tibial nerve and the tendon of flexor digitorum longus to reach the plantar surface of the foot.
• Gives off the following branches

1. Circumflex fibular a.
2. fibular a.
3. communicating branch (unites pisterior tibial and fibular aa)
4. posterior medial malleolar a.
5. medial calcaneal arteries
6. medial and lateral plantar arteries

Question 13

Describe the fibular a.

Answer 13

AKA peroneal a.

Provides major blood supply to the lateral crural compartment. Branches from the proximal portion of the posterior tibial artery and passes laterally, descending within the substance of the flexor hallucis longus muscle on the posterior surface of the fibula.

Gives off the following branches:

1. muscular
2. nutrient artery to fibula
3. communicating branch (with posterior tibial a.)
4. perforating a.
5. posterior lateral malleolar a.

Question 14

Describe the genicular anastamosis

Answer 14

Provides rich blood supply to the capsile of the knee joint and surrounding musculature. Composed of ten vessels which arise from the lateral femoral circumflex a., the femoral a., popliteal a., anterior and posterior tibial aa. to form both a superficial plexus which provides blood to the muscles in the area of the knee and a deep plexus which lies directly upon the capsule of the knee joint itself.

Question 15

Describe the sciatic nerve

Answer 15

L4,5 S1,2,3

Descends within the popliteal fossa, bifurcates into the tibial n and common fibular n.

Question 16

Describe the route of the tibial n

Answer 16

• L4,5 S1,2,3
• Located superficially and centrally within the popliteal fossa
• while in the popliteal fossa, gives branches to the plantaris and gastrocnemius muscles (sural branches) as well are a cutaneous nerve to the posterior leg - the medial sural cutaneous n.
• Leaves the popliteal fossa deep to the gastrocnemius muscle
• at the superior edge of the soleus provides muscular branches to the popliteus and soleus before passing deep to the soleus muscle
• descends between the superficial and deep posterior muscular compartments in company with the posterior tibial artery and veins (neurovascular bundle)
• innervates ALL posterior leg musculature
• exits the leg by passing behind the medial malleolus between the posterior tibial artery and the tendon of the flexor hallucis longus muscle.

Question 17

From anteromedial to posterolateral, what is the order of structures as they pass beneath the flexor retinaculum?

Answer 17

Tom, Dick, a.n. Harry

Tibialis posterior

flexor Digitorum longus

posterior tibial Artery

tibial Nerve

flexor Hallucis longus

Question 18

To what does the saphenous nerve provide cutaneous innervation?

Answer 18

medial surface of foot and the medial posterior surface of heel.

Question 19

Describe the common fibular nerve

Answer 19

1. L4,5 - S1,2
2. Courses superficially and laterally within the popliteal fossa
3. provides the lateral sural cutaneous nerve to the posterior leg while in the popliteal fossa
4. as it leaves the popliteal fossa, continues to follow the course of the biceps femoris tendon to the head of the fibula
5. pierces the fibularis longus muscle inferior to the head of the fibula where it divides into the superficial and deep fibular nn

Question 20

describe the superficial fibular n

Answer 20

1. (L5 - S1,2)
2. Descends along the fibula between the muscles of the lateral and anterior compartments
3. Provides muscular branches to the fibularis longus and brevis
4. becomes superficial in the distal third of the leg to innervate the anterior distal third of the leg and divide into medial and intermediate dorsal cutaneous nerves which provide dorsal digital branches to all the toes (except those provided by the deep fibular n)

Question 21

Describe the deep fibular n.

Answer 21

1. L4,5
2. Branches from the common fibular n within the substance of the fibularis longus muscle at the lateral neck of the fibula
3. passes into the anterior compartment by piercing the extensor digitorum longus muscle
4. descends through the anterior compartment lateral to the anterior tibial artery and veins
5. innervates all the muscles of the anterior compartment
6. passes deep to the extensor retinacula, lies lateral to the dorsalis pedis artery and, as it crosses the ankle divides into lateral and medial terminal branches

Question 22

Describe the lateral and medial branches of the deep fibular n.

Answer 22

1. Lateral branch - passes deep to the exxtensor digitorum brevis muscle (which it innervates) and contributes sensory fibers to joints of the foot.
2. Medial branch - follows the course of the first dorsal metatarsal artery to cutaneously innervate the web between the first and second toes.

Question 23

What is the destiny of the terminal branch of the femoral nerve, the saphenous nerve? (L4)

Answer 23

Descends the leg medially, and with the greater saphenous v. will provide cutaneous sensation to the medial portion of the leg and foot, and the posterior portion of the dorsum of the foot.

Question 24

If a patient has parasthesia in the web between the big toe and it’s neighbor, what nerve is likely damaged?

Answer 24

Deep branch of the fibular Nerve