Posterior leg

Question 1

What separates the superficial posterior muscle group and the deep posterior muscle group?

Answer 1

Transverse septum; Tibial nerve and posterior tibial vessels are deep to the transverse crural intermuscular septum

Question 2

What is the most superficial posterior leg muscle?

Answer 2

Gastrocnemius

Question 3

Origins of the 2 heads of gastrocnemius

Answer 3

Medial head : popliteal surface above medial femoral condyle

Lateral head : Lateral femoral condyle

Question 4

Insertion, innervation and action of gastrocnemius

Answer 4

Insertion: Posterior calcaneal tendon
Innervation: Tibial nerve
Action: Plantarflexion with extended leg, raise heel, flex leg

Question 5

Where may a fabella be located?

Answer 5

Close to lateral head of gastrocnemius proximal attachment

Question 6

What is a fabella and why could it be bad?

Answer 6

It is a sesamoid bone that may be very painful if stress fractured during total knee replacement

Question 7

Where does soleus lie?

Answer 7

Deep to gastrocnemius

Question 8

Origin, insertion, innervation and action of Soleus

Answer 8

O: Posterior head and upper body of fibula and soleal line on tibia
I: Calcaneal tendon
Innervation: Tibial nerve
Action: plantarflexion

Question 9

What forms the triceps surae?

Answer 9

The 2 heads of gastrocnemius and soleus – calf prominence

Question 10

Origin, insertion, innervation and action of Plantaris

Answer 10

O: Inferior aspect of lateral supracondylar line
I: Calcaneal tendon
Innervation: tibial nerve
Action: Proprioception of where foot is, weak assist in plantarflexion

Question 11

What is unique about Plantaris?

Answer 11

It is small but has a very long tendon that runs between gastrocnemius and soleus

Question 12

What 2 things can happen to the plantaris tendon?

Answer 12

Used for reconstructive hand tendon surgery

Can also be ruptured during violent ankle movements of athletes – they will not be able to bare any weight

Question 13

What muscle lies deep to plantaris?

Answer 13

Popliteus

Question 14

Origin, insertion, innervation and action of poplietus

Answer 14

O: Lateral femoral condyle and lateral meniscus
I: Superomedial to soleal line on posterior tibia
Innervation: tibial nerve
Action: Weak flexion of knee, unlocks extended leg with lateral rotation of femur

Question 15

What is the largest deep posterior leg muscle?

Answer 15

Flexor hallucis longus

Question 16

Origin, insertion, innervation and action of flexor hallucis longus

Answer 16

O: Inferior fibula
I: Base of 1 distal phalanx (big toe)
Innervation: tibial nerve
Action: flex great toe (hallux) and plantarflexion

Question 17

Origin, insertion, innervation and action of flexor digitorum longus

Answer 17

O: inferior to soleal line on posterior tibia
I: Base of 2-5th distal phalanges
Innervation: tibial nerve
Action: flex digits 2-5 and plantarflexion

Question 18

Origin, insertion, innervation, and action of posterior tibialis

Answer 18

O: SAME PLANE AS BONES - interosseous membrane, inferior to soleal line on tibia, posteromedial side of fibula
I: Navicular tuberosity, cuneiforms, 2-4 metatarsals
Innervated by tibial nerve
Action: Plantarflexion and innerversion

Question 19

What nerve innervates every muscle in the posterior leg?

Answer 19

Tibial Nerve

Question 20

Where can you palpate the posterior tibial artery?

Answer 20

Posterior to medial malleolus btwn medial calcaneal tendon and have pt invert their foot

Question 21

Why would you need to palpate the posterior tibial artery?

Answer 21

It is used to examine patients that have occlusive peripheral artery disease
They will present with leg cramps and pain during walking that goes away after rest

Question 22

Describe the sciatic nerve splitting down the leg?

Answer 22

Sciatic splits into tibial and common fibular
Common fibular gives rise to lateral sural cutaenous
Tibial gives rise to medial sural cutaneous that runs with the small saphenous vein
The medial sural cutaneous joins with a communicating sural to form the sural nerve proper

Question 23

Describe the popliteal artery splitting down the leg?

Answer 23

Popliteal artery splits into the posterior tibial and anterior tibial
The anterior tibial goes superior anterior at interosseous membrane
The posterior tibial gives off a fibular branch
The posterior runs down the leg and eventually splits in to the medial and lateral plantar arteries

Question 24

What tendons contribute to dynamic arch support of the foot?

Answer 24

Tibialis posterior, tibialis anterior, flexor hallucis longus, fibularis longus, intrinsic plantar muscles

Question 25

What ligaments contribute to the passive arch support of the foot?

Answer 25

Plantar aponeurosis, long plantar, short plantar, plantar calcaneonavicular

Question 26

What is the order of the deep posterior leg muscles as the pass the medial side of the foot?

Answer 26

Tom - tibialis posterior
Dick - flexor digitorum longus
a.n. - posterior tibial artery and tibial nerve
Harry - flexor hallucis longus