Popliteal Fossa and Leg

Question 1

Anterior Compartment Muscles General function

Answer 1

dorsiflexion and inversion of the foot

Question 2

Anterior Compartment Muscles Innervation

Answer 2

Deep fibular nerve

Question 3

Anterior Compartment Muscles Arterial Supply

Answer 3

Tibial Artery

Question 4

Anterior Compartment Muscles List (4)

Answer 4

1. Tibialis anterior
2. Extensor digitorum longus
3. Extensor hallucis longus
4. Fibularis tertius

Question 5

Tibialis anterior

Answer 5

a. Origin – superolateral surface of tibia and interosseous membrane
b. Insertion – dorsal surface of medial foot (medial cuneiform and first metatarsal)
c. Function – dorsiflexion and inversion of foot
d. Innervation – deep fibular n. (L4,L5)

Question 6

Extensor digitorum longus

Answer 6

a. Origin – anteromedial surface of fibula and interosseous membrane
b. Insertion – dorsal surface of middle and distal phalanges of toes (forms extensor expansion of toes)
c. Function – dorsiflexion of foot; extension of 4 lateral toes
d. Innervation – deep fibular n. (L4,L5)

Question 7

Extensor hallucis longus

Answer 7

a. Origin – anterior surface of fibula and interosseous membrane
b. Insertion – dorsal surface of distal phalanx of great toe
c. Function – dorsiflexion of foot; extension of great toe
d. Innervation – deep fibular n. (L4,L5)

Question 8

Fibularis tertius

Answer 8

a. Origin – anterior surface of distal fibula and interosseous membrane
b. Insertion – 5th metatarsal
c. Function – dorsiflexion and aids in eversion of foot
d. Innervation – deep fibular n. (L4,L5)

Question 9

Lateral Compartment Muscles

- General function

Answer 9

Plantarflexion and eversion of the foot

Question 10

Lateral Compartment Muscles

- General Innervation

Answer 10

Motor innervation is from the superficial fibular nerve

Question 11

Lateral Compartment Muscles

- arterial supply

Answer 11

The fibular and anterior tibial aa

Question 12

Lateral Compartment Muscles

-List (2)

Answer 12

Fibularis longus

Fibularis brevis

Question 13

Fibularis longus

Answer 13

a. Origin – superolateral surface of fibula
b. Insertion – ventral surface of medial foot (medial cuneiform and first metatarsal)
c. Function – plantarflexion and eversion of foot
d. Innervation – superficial fibular n. (L5, S1, S2)

Question 14

Fibularis brevis

Answer 14

a. Origin – Inferolateral surface of fibula
b. Insertion – base of 5th metatarsal
c. Function – plantarflexion and eversion of foot
d. Innervation – superficial fibular n. (L5, S1, S2)

Question 15

Superficial Posterior Leg Muscles

Answer 15

Gastrocneumius
Soleus
Plantaris

Question 16

Gastrocneumius

Answer 16

1. Origin – lateral femoral condyle (lateral head); medial femoral condyle (medial head)
2. Insertion – via calcaneal tendon to calcaneus
3. Function – plantarflexion of foot; assists with flexion of knee
4. Innervation – Tibial n. (S1, S2)

Question 17

Soleus

Answer 17

1. Origin – soleal line of tibia and superior fibula
2. Insertion – via calcaneal tendon to calcaneus
3. Function – plantarflexion of foot
4. Innervation – Tibial n. (S1, S2)

Question 18

Plantaris

Answer 18

1. Origin – lateral femoral condyle
2. Insertion – via calcaneal tendon to calcaneus
3. Function – weakly flexes leg, plantarflexion of foot; proprioception
4. Innervation – Tibial n. (S1, S2)
5. CLINICAL CORRELATION – because of clinical insignificance, the plantaris can be removed without consequence for muscle grafting.
   CLINICAL CORRELATION – this muscle can sometimes be painfully ruptured during strenuous activities.

Question 19

Deep Posterior Leg Muscles

Answer 19

Popliteus
Flexor digitorum longus
Tibialis posterior
Flexor hallucis longus

Question 20

Popliteus

Answer 20

1. Origin – lateral femoral condyle
2. Insertion – posterior surface of tibia superior to soleal line.
3. Function – unlocks know by rotating femur laterally on tibia; flexes knee; medially rotates tibia when foot unsupported.
4. Innervation – Tibial n. (L4, L5, S1)
5. Popliteal bursa lies deep to tendon of muscle.
6. Forms floor (anterior wall) of the popliteal fossa; deep to arteries, veins, and nn.

Question 21

Flexor digitorum longus

Answer 21

1. Origin – posterior surface of tibia
2. Insertion – distal phalanges of toes 2-5
3. Function – flexion of toes 2-5; plantarflexion of foot
4. Innervation – Tibial n. (S2, S3)

Question 22

Tibialis posterior

Answer 22

1. Origin – posterior surface of tibia and fibula; interosseous membrane
2. Insertion – plantar surfaces of navicular, cuneiform, cuboid, calcaneus, bases of metatarsals
3. Function – plantarflexion and inversion of foot
4. Innervation – Tibial n. (L4, L5)

Question 23

Flexor hallucis longus

Answer 23

1. Origin – Posterior fibula and interosseous membrane
2. Insertion – distal phalanx of great toe
3. Function – plantarflexion of foot; flexion of great toe
4. Innervation – Tibial n. (S2, S3)

Question 24

Boundaries of popliteal fossa

Answer 24

1. Superomedial – semitendinosus and semimembranosus
2. Superolateral – biceps femoris
3. Inferomedial – medial head of gastrocnemius
4. Inferolateral – lateral head of gastrocnemius
5. Anterior – knee joint capsule and popliteus
6. Posterior – skin of knee and popliteal fascia

Question 25

Contents of popliteal fossa

Answer 25

1. Fat 2. Termination of small (lesser) saphenous vein 3. Terminal portion of posterior cutaneous nerve of thigh 4. Popliteal lymph nodes 5. Sciatic nerve typically splits into common fibular and tibial nerves within popliteal fossa. 6. Popliteal vein 7. Popliteal artery

Question 26

Lymph Nodes of Popliteal Fossa

Answer 26

1. Superficial popliteal lymph nodes – drain to deep popliteal lymph nodes 2. Deep popliteal lymph nodes – drain to deep inguinal lymph nodes

Question 27

Tibial nerve | -spinal segments

Answer 27

L4, L5, S1, S2, S3

Question 28

Tibial Nerve Motor Supply (7)

Answer 28

1. Gastrocnemius 2. Plantaris 3. Soleus 4. Popliteus 5. Tibialis posterior 6. Flexor digitorum longus 7. Flexor hallucis longus

Question 29

Tibial Nerve Sensory Supply

Answer 29

Via medial sural component of sural nerve supplies sensory innervation to posterolateral leg and foot.

Question 30

Common Fibular Nerve Spinal Segments

Answer 30

L4, L5, S1, S2

Question 31

Lateral sural cutaneous nerve

Answer 31

Branch of common fibular | – supplies lateral side of leg and foot

Question 32

Deep fibular nerve

Answer 32

Branch of Common Fibular, L4, L5, S1, S2 | Nerve of anterior leg compartment

Question 33

Deep fibular nerve Motor (6)

Answer 33

1. Tibialis anterior 2. Extensor digitorum longus 3. Extensor hallucis longus 4. Fibularis tertius 5. Extensor digitorum brevis (dorsum of foot) 6. Extensor hallucis brevis (dorsum of foot)

Question 34

Deep fibular nerve SENSORY

Answer 34

area between toes 1 and 2 (dorsal digital nn)

Question 35

Superficial fibular nerve

Answer 35

Branch of Common fibular L4, L5, S1, S2

Question 36

Superficial fibular nerve Motor supply to:

Answer 36

1. Fibularis longus | 2. Fibularis brevis

Question 37

Superficial fibular nerve Sensory:

Answer 37

1. Anterior-inferior leg | 2. Dorsum of foot except for small area supplied by deep fibular nerve.