9-2a. Posterior Compartment Conference

Question 1

Near the lateral edge of the Achilles tendon, what two structures run in close proximity to each other within the superficial fascia?

Answer 1

Small saphenous vein

Sural nerve

Question 2

What specific nerves supply the cutaneous innervation to the skin on the posterior aspect of the leg?

Answer 2

• Posterior femoral cutaneous
• Lateral sural cutaneous
• Medial sural cutaneous
• Saphenous
• Superficial fibular
• Sural

**NEED PICTURE HERE

Question 3

What dermatomes are on the posterior leg?

Answer 3

S2, S1, L4, L5

**NEED PICTURE HERE

Question 4

What separates the posterior compartment from the anterior and lateral compartments?

Answer 4

1. Tibia
2. Interosseous membrane
3. Fibula
4. Posterior Intermuscular septum

Question 5

What separates the superficial posterior compartment from the deep posterior compartment?

Answer 5

Deep transverse intermuscular septum

Question 6

What nerve supplies the motor innervation to the muscles of the posterior compartment?

Answer 6

Tibial N

Question 7

What is the main blood supply to the muscles of the posterior compartment?

Answer 7

Branches off the Popliteal A, Posterior Tib A, and Fibular A,

Question 8

What is the common function of the posterior compartment muscles?

Answer 8

All except popliteus plantarflex the ankle and most contribute to inversion of the foot.

Question 9

Where are you most likely to find the fabella sesamoid?

Answer 9

In the lateral head of the gastrocnemius.

Question 10

A fabella located within the lateral head of the gastrocnemius is in close proximity to what nerve?

Answer 10

Common fibular/peroneal N

• Symptoms of irritations:
• local tenderness
• pain from knee down to dorsum of foot
• muscle paralysis

Question 11

What nerve can become entrapped in the tendinous arch at the proximal end of soleus?

Answer 11

Tibial nerve
(Travels through the popliteal fossa then deep to the gastroc heads, posterior to popliteus and the popliteal artery--> then passes through the tendinous arch  to travel deep to soleus)

Question 12

What are the two bursa located at the insertion of the Achilles tendon?

Answer 12

1. Retrocalcaneal bursa (subtendinous bursa of calcaneal tendon)
2. Subcutaneous calcaneal bursa

Question 13

What is a Haglund’s deformity?

Answer 13

Apposition of bone “pump bumb” on the superior aspect of the posterior calcaneus.
Potential cause of bursitis and Achilles tendinopathy.

Question 14

Where is Kager’s triangle located?

Answer 14

Its is the space anterior to the Achilles tendon, posterior to the tarsal tunnel, and superior to the posterior calcaneus.
It is filled with fat.
It separates the Achilles tendon from the deep transverse intermuscular septum.

Question 15

Before dividing into 4 digital tendons in the plantar foot, the flexor digitorum longus receives the insertion from what muscle?

Answer 15

Quadratus plantae

Question 16

What muscles does FDL provide origins for (as it divides into 4 digital tendons)?

Answer 16

Four lumbricals

Question 17

What other muscle tendon does the FHL tendon often share tendinous slips with?

Answer 17

FDL distal to the navicular

Question 18

What is the band of tissue that binds the FHL to the FDL against the navicular?

Answer 18

Master Knot of Henry

Question 19

Distally in the leg, Tibialis Posterior veers medially and crosses deep to what muscle?

Answer 19

FDL

Question 20

Crossing inferior to the plantar calcaneonavicular (spring) ligament, the TP tendon contains what?

Answer 20

Sesamoid

Question 21

During which portions of the gait cycle is the posterior compartment active (as a group)?

Answer 21

Flatfloot
Midstance
Terminal stance

Question 22

What is the role of the posterior compartment muscles (as a group) during flatfoot in the gait cycle?

Answer 22

Loading response/weight acceptance

- decelerates mass by moderating ankle dorsiflexion and supports the medial longitudinal arch

Question 23

What is the role of the posterior compartment muscles (as a group) during midstance in the gait cycle?

Answer 23

Preserves momentum by controlling ankle dorsiflexion and helps restore the medial longitudinal arch

Question 24

What is the role of the posterior compartment muscles (as a group) during terminal stance in the gait cycle?

Answer 24

Burst in activity

- accelerates mass by plantarflexing ankle and causing heel-lift meanwhile stabilizing the forefoot for propulsion

Question 25

What are the branches of the fibular artery?

Answer 25

• Nutrient artery of the fibula
• Perforating branch (passes through inferior opening of the interosseous membrane)
• Communicating branch
• Posterior lateral malleolar arteries

Question 26

What are the branches of the posterior tibial artery?

Answer 26

• Nutrient artery of the tibia
• Fibular A
• Communicating branch
• Posterior medial malleolar arteries
• Medial calcaneal arteries

Question 27

What are the branches of the tibial nerve in the foot?

Answer 27

• Medial calcaneal branches
• Medial plantar nerve
• Lateral plantar nerve

Question 28

In a case of medial calcaneal nerve entrapment, what structures does the medial calcaneal nerve get sandwiched between?

Answer 28

The deep fascia over the abductor hallucis and the anterior-medial edge of the calcaneal tuberosity.
The deep fascia is thick and elastic, therefore the nerve is vulnerable.

Question 29

What dermatome(s) cover the heel?

Answer 29

S1