Posterior Leg

Question 1

The talus contains a structure known as the posterior process which has a medial and lateral tubercle. What is the significance of these two tubercles?

Answer 1

Creates a groove for the FHL tendon

Question 2

What does the calcaneus articulate with?

Answer 2

Talus superiorly

Cuboid anteriorly

Question 3

What is the sustentaculum tali?

Answer 3

A ligament or shelf like projection that supports the talus and provides a groove for the FHL

Question 4

What does the navicular bone articulate with?

Answer 4

Head of talus posteriorly
Cuneiforms anteriorly
Cuboid laterally

Question 5

What is the significance of the navicular tuberosity?

Answer 5

Site of tibialis posterior attachment

Question 6

What divides the posterior compartment of the leg into deep and superficial groups?

Answer 6

Transverse septa

Question 7

Which muscles are in the superficial posterior compartment of the leg?

Answer 7

Gastrocnemius, soleus and plantaris

Question 8

Which muscles are in the deep posterior compartment of the leg?

Answer 8

Popliteus, FHL, FDL, and tibialis posterior

Question 9

Where are the tibial nerve and posterior tibial vessels located within the posterior compartment?

Answer 9

Deep to transverse crural intermuscular septum

Question 10

Which nerve innervates all the muscles within the posterior compartment of the leg?

Answer 10

Tibial nerve

Question 11

Structures in each compartment of the leg share what components?

Answer 11

Same general function, nerve, artery and vein

Question 12

What is the most superficial muscle in the posterior compartment and that also crosses both the knee and ankle joints?

Answer 12

Gastrocnemius

Question 13

What are the sites of origin for the medial and lateral heads of the gastrocnemius?

Answer 13

Medial head: medial femoral condyle

Lateral head: lateral femoral condyle

Question 14

What is the insertion site for the gastrocnemius muscle?

Answer 14

Posterior surface of calcaneus via tendon calcaneus (Achilles tendon)

Question 15

What is the overall action of the posterior compartment muscles?

Answer 15

Plantarflexion

Question 16

What is the unique action of the gastrocnemius?

Answer 16

Flexes leg at the knee joint

Question 17

The lateral head of the gastrocnemius may have a sesamoid bone close to its proximal attachment known as a fabella. What is its function and clinical significance?

Answer 17

Possibly provide leverage for lateral head of gastrocnemius

Painful fabellar stress fracture may accompany total knee replacement

Question 18

What are the proximal attachments for the soleus muscle?

Answer 18

Soleal line of tibia, posterior head of fibula and superior 1/4 of posterior fibula

Question 19

What does the soleus insert on?

Answer 19

Into posterior surface of calcaneus via tendo calcaneus (Achilles tendon)

Question 20

What do the gastrocnemius and soleus form?

Answer 20

A tripartite muscle known as the triceps surae which forms the calf prominence

Question 21

What are the attachment sites for the plantaris muscle?

Answer 21

O: lateral supracondylar line
I: posterior surface of calcaneus via calcaneal tendon

Question 22

What is the course of the plantaris tendon?

Answer 22

Runs between gastrocnemius and soleus

Question 23

Which muscle of the superficial posterior compartment is proposed to be a proprioceptive organ for foot position?

Answer 23

Plantaris muscle (has a high density of proprioceptive receptors)

Question 24

What are the unique actions of the plantaris muscle?

Answer 24

Only weak plantarflexion

Leg flexion

Question 25

Which posterior compartment muscle forms the floor of the popliteal fossa?

Answer 25

Popliteus

Question 26

What are the attachments for the popliteus muscle?

Answer 26

O: posterior tibia superior to soleal line I: lateral femoral condyle and lateral meniscus

Question 27

What are the unique functions of the popliteus muscle?

Answer 27

Unlocks extended leg by laterally rotating femur on a stationary tibia Weakly flexes leg

Question 28

Which structures does the popliteus separate?

Answer 28

The laterall collateral L from the lateral meniscus

Question 29

What are the attachment sites for FHL?

Answer 29

O: inferior 2/3 of posterior fibula I: base of distal phalanx of great toe

Question 30

What are the unique actions for the FHL muscle?

Answer 30

Flexes great toe

Question 31

What are the attachment sites for FDL?

Answer 31

O: posterior tibia inferior to soleal line I: distal phalanx base of lateral 4 digits

Question 32

Describe the course of FDL’s tendon

Answer 32

Passes posterior to tibialis posterior -> passes diagonally in sole of the foot superficial to FHL tendon -> divides into four tendons in the middle of the sole of the foot that pass to lateral 4 digits

Question 33

What is the unique action of FDL?

Answer 33

Flexes lateral 4 digits

Question 34

What is the proximal attachment for the tibialis posterior muscle?

Answer 34

Interosseous membrane, posterior tibia to soleal line, posteromedial surface of fibula

Question 35

What is the distal attachment for tibialis posterior?

Answer 35

Navicular tuberosity, cuneiforms and 2-4 metatarsal bones

Question 36

What is the deepest posterior compartment muscle?

Answer 36

Tibialis posterior

Question 37

What is the unique action for the tibialis posterior muscle?

Answer 37

Inversion

Question 38

Where are the superior medial and lateral genicular arteries located?

Answer 38

Just superior to medial and lateral head of the gastrocnemius

Question 39

Where is the inferior medial genicular A located?

Answer 39

Deep to medial head of gastrocnemius

Question 40

Where is the inferior lateral genicular artery located?

Answer 40

Deep to plantaris and superficial to popliteus

Question 41

Do genicular arteries branch into muscles?

Answer 41

NO

Question 42

Describe the course of the tibial nerve

Answer 42

Passes with posterior tibial vessels deep to soleus and posterior to tibialis posterior Leaves posterior compartment by passing deep to flexor retinaculum b/w medial malleolus and calcaneus

Question 43

How does the tibial nerve end?

Answer 43

By dividing into medial and lateral plantar nerves (posteroinferior to medial malleolus)

Question 44

Describe the course of the posterior tibial A

Answer 44

Begins near inferior border of popliteus Passes inferomedially on posterior surface of tibialis posterior w/ tibial nerve Runs deep to flexor retinaculum Ends by dividing into medial and lateral plantar arteries

Question 45

What is the largest branch of the posterior tibial A?

Answer 45

Fibular A

Question 46

Describe the course of the fibular A

Answer 46

Begins inferior to distal border of popliteus Descends towards fibula under the FHL Ends by piercing interosseous membrane and anastomosing with anterior lateral malleolar A

Question 47

Which artery vascularizes the posterior compartment?

Answer 47

Posterior tibial A and fibular A

Question 48

What is the tendon of the plantaris muscle commonly used for?

Answer 48

In reconstructive surgery of hand tendons | It’s removal doesnt affect knee or ankle movements

Question 49

What can rupture during violent ankle movements?

Answer 49

Plantaris tendon Common injury in basketball players, sprinters and ballet dancers Pain may be so severe that person in unable to bear weight

Question 50

Where can the posterior tibial pulse be palpated?

Answer 50

Between posterior surface of medial malleolus, medial border of calcaneal tendon and deep to flexor retinaculum (important to have pt relax this by inverting foot)

Question 51

What is the posterior tibial pulse used for?

Answer 51

Examining patients with occlusive peripheral artery disease (intermittent claudication)

Question 52

What causes peripheral occlusive artery disease?

Answer 52

Condition caused by ischemia of leg muscles due to narrowing or occlusion of leg arteries Characterized by leg crams and pain during walking (disappears after rest)