Lecture 16: Anterolateral Leg

Question 1

Where is the fibular trochlea located?

Answer 1

ON the ridge on the lateral surface of the calcaneus

Question 2

What is the most lateral bone in the distal row of tarsus bones of the foot?

Answer 2

Cuboid

Question 3

What muscle tendon inserts on the cuboid sulcus (groove)>

Answer 3

Fibularis longus

Question 4

What does crural/srural mean?

Answer 4

Leg

Question 5

What does crural fascia cover?

Answer 5

Leg muscles

Question 6

Crural fascia thickens dismally to form what?

Answer 6

Extensor retinaculum

Question 7

What is the function of extensor retinaculum?

Answer 7

Prevents bowstringing during dorsiflexion

• Functions to hold tendons against bone

Question 8

Why do tendons of the foot run to the sides of the foot?

Answer 8

Because if they ran straight down the middle they would impede our walking.

• Tendons of the hand dont do this because we dont walk on our hands so its no big deal

Question 9

What are the primary functions of muscles in the anterior compartment of the leg?

Answer 9

Dorsiflexion

Toe extension

Question 10

What muscles make up the anterior compartment of the leg?

Answer 10

Tibialis anterior
Extensor hallucis longus
Extensor digitorum longus
Fibularis tertius

Question 11

What are the functions of the tibialis anterior muscle?

Answer 11

Dorsiflexion

Inversion of foot

Question 12

What is the “shin splint” muscle?

Answer 12

Tibialis anterior

Question 13

The tibialis anterior attaches dismally on the medial surface of the first cuneiform and first metatarsal base, almost in the exact same spot as what other muscle?

Answer 13

Tibialis posterior

• Both are strong inverters of the foot but come from 2 different compartments and are innervated by 2 different nerves

Question 14

The tibialis posterior and anterior muscles are both inverting and both maintaining the arch of the foot, but which muscle is the main contributor to arch support?

Answer 14

Tibialis posterior

Question 15

Each of the 4 tendons of the extensor digitorum longus muscle forms an ____________ ______________ over the dorsum of the lateral 4 proximal phalanges that divide into what 2 things?

Answer 15

Extensor expansion; 2 lateral slips (distal phalanx) and one central slip (middle phalanx)

Question 16

What are the functions of the extensor digitorum longus muscle?

Answer 16

Extends lateral 4 digits

Dorsiflexion

Question 17

What muscle fuses with the extensor digitorum longus muscle proximally?

Answer 17

Fibularis tertius

• tendon doesnt attach to a digit

Question 18

What are the functions of the fibularis tertius muscle?

Answer 18

Dorsiflexion

Eversion

Question 19

What muscle is found lateral to the tibialis anterior muscle?

Answer 19

Extensor hallucis longus muscle

Question 20

What are the functions of the extensor hallucis longus muscle?

Answer 20

Extend hallux

Dorsiflexion

Question 21

Extension and dorsiflexion is the general theme of the anterior compartment muscles with the exception of what muscle?

Answer 21

Fibularis tertius

Question 22

What nerve does the deep fibular nerve branch off from?

Answer 22

Common fibular nerve

Question 23

What 2 things does the common fibular nerve branch into?

Answer 23

Deep fibular nerve and superficial fibular nerve

Question 24

What portions of the skin does the deep fibular nerve innervate?

Answer 24

Skin between the first and second digits of the foot

Question 25

If you poke someone between the first and second digits of the foot and they don’t feel it then there is damage to what nerve?

Answer 25

Deep fibular nerve

Question 26

What nerve supplies the majority of the top of the foot?

Answer 26

Superficial fibular nerve

Question 27

What does the anterior tibial artery arise from?

Answer 27

Popliteal artery

Question 28

Muscles in the _________ compartment of the foot are powerful everts of the foot

Answer 28

Lateral

Question 29

If a pt was unable to evert their foot due to muscles not working properly, they would constantly sprain their ankle bc it would constantly be rolling in when they walked. What compartment of muscles would be defective?

Answer 29

Lateral compartment of the foot

Question 30

What is the most superficial muscle in the lateral compartment of the leg and extends from the fibular head to the sole of the foot?

Answer 30

Fibularis longus muscle

Question 31

Only true fibular muscles can assist in what function?

Answer 31

Plantar flexion

Question 32

What muscle is found just deep to fibularis longus?

Answer 32

Fibularis brevis muscle

Question 33

What are the functions of the true fibularis muscles (fibularis brevis and fibularis longus)?

Answer 33

Eversion

Plantarflexion

Question 34

What is the most commonly injured extremity nerve and why?

Answer 34

Common fibular nerve bc it binding superficially around the fibular head

Question 35

What does injury to the common fibular nerve result in?

Answer 35

Paralysis of all anterior and lateral crural muscles

Question 36

If a pt comes in with foot-drop (caused by dorsiflexion and eversion), what is the most likely cause?

Answer 36

Damage to common fibular nerve

Question 37

What is foot drop?

Answer 37

• Loss of dorsiflexion and eversion of the foot making it difficult to achieve heel strike

Question 38

What does the gait of a pt with damage to the common fibular nerve look like?

Answer 38

Pt has high stepping gait, waddling gait, or a swing-out gait

Question 39

If a pt with foot drop has a leg that swings strongly forward and strikes with a clop, what does this indicate?

Answer 39

Loss of sensation along anterolateral leg and dorsum of foot

Question 40

What is the one compartment of the leg that doesnt have a distinct arterial branch accompanying the compartment nerve?

Answer 40

Lateral compartment

Question 41

What might trauma to septa lead to?

Answer 41

Hemorrhage, edema, inflammation

Question 42

What might intraccomparmental pressure in the leg lead to?

Answer 42

Ischemia and permanent injury