Anterior Leg

Question 1

What separates the anterior and posterior compartment?

Answer 1

Interosseous membrane

Question 2

What separates the anterior and lateral compartment?

Answer 2

Anterior septum

Question 3

What is the location of the anterior compartment?

Answer 3

Anterior to interosseous membrane

Question 4

What is the general function of the anterior compartment of the leg?

Answer 4

Dorsiflexion and toe extension

Question 5

What muscles are located in the anterior leg compartment?

Answer 5

Tibialis anterior, extensor hallucis longus, extensor digitorum longus and fibularis tertius

Question 6

What are the attachment sites for tibialis anterior?

Answer 6

O: lateral tibial condyle and superolateral 1/2 of tibia
I: medial surface of 1st cuneiform and 1st metatarsal base

Question 7

What is a unique function of tibialis anterior?

Answer 7

Inversion

Question 8

What is the proximal attachment for extensor hallucis longus?

Answer 8

Anteromedial fibular surface and interosseous membrane

Medial to distal half of the proximal attachment of extensor digitorum longus

Question 9

What is the insertion site for extensor hallucis longus?

Answer 9

Base of distal phalanx of hallux

Question 10

What are the functions of extensor hallucis longus?

Answer 10

Extend hallux and dorsiflex ankle

Question 11

What is the proximal attachment of extensor digitorum longus?

Answer 11

Lateral tibial condyle, anterior fibular surface and interosseous membrane

Question 12

What is the distal attachment of extensor digitorum longus?

Answer 12

Each of the four tendons forms an extensor expansion over the dorsum of lateral 4 proximal phalanges that divide into two lateral slips (distal phalanx) and one central slip (middle phalanx)

Question 13

What are is the unique action of extensor digitorum longus?

Answer 13

Extends lateral four digits

Question 14

What are the attachment sites for fibularis tertius?

Answer 14

O: anteroinferior fibular surface
I: dorsum of 5th metatarsal base

Question 15

What is a unique action for fibularis tertius?

Answer 15

Eversion

Question 16

What are some characteristics of the fibularis tertius muscle?

Answer 16

Fuses with digitorum longus proximally
Tendon does not attach to a digit
Variably present

Question 17

What innervates the anterior compartment of the leg?

Answer 17

Deep fibular nerve

Question 18

Describe the course of the deep fibular nerve

Answer 18

Begins b/w fibula and fibularis longus muscle
Runs inferomedially with anterior tibial vessels between tibialis anterior and extensor hallucis longs
Ends in medial and lateral terminal branches on dorsum of the foot

Question 19

What other structures does the deep fibular nerve supply?

Answer 19

Ankle joint and metacarpal phalangeal joints
Dorsal intrinsic foot muscles
Skin between 1st and 2nd digits*

Question 20

What is the anterior tibial artery a branch of?

Answer 20

Popliteal artery

Question 21

Describe the course of the anterior tibial A

Answer 21

Begins near inferior border of popliteus
Passes anteriorly over interosseous membrane
Descends on anterior surface of interosseous membrane between EHL and TA muscles with deep fibular nerve
Ends at ankle between malleoli to become dorsalis pedis A

Question 22

What marks the approximate point of division of the anterior and posterior tibial arteries from the popliteal A?

Answer 22

Tibial tuberosity

Question 23

What are shin splints?

Answer 23

Due to repetitive microtrauma to tibialis anterior including small tears to periosteum over the tibia and/or tears to overlying deep fascia
A mild form of compartmental syndrome (swelling of TA due to repetitive ground reaction force)