Anterior Leg

Question 1

Anterior Compartment Muscles (overview)

Answer 1

1. Tibailis anterior
2. Extensor Hallucis Longus
3. Extensor Digitorum Longus
4. Fibularis Tertius

Dorsiflexion/toe extension

Innvervation:

a) deep fibular n.
vascularization:
a) anterior tibial n

Question 2

Long thick muscle on anterolateral surface of tibia

Answer 2

tibalis anterior

Anterior compartment toe extensor/dorsiflexor

proximal attachment: lateral tibial condyle and superolateral 1/2 of tibia

distal attachment: medial surface of first cuneiform and first metatarsal base

function: dorsiflexion and inversion

Question 3

Forms an extensor expansion over dorsum of lateral four proximal phalanges that divide _____________

Answer 3

two lateral slips (distal phalanx) and one central slip (middle phalanx)

Extensor digitorum longus

functions: extends lateral four digits + dorsiflexion

Question 4

VARIABLY present

Tendon does not attach to a digit, and fuses with digitorum longus proximally

Answer 4

Fibularis tertius

Proximal: anteroinferior fibular surface
Distal: dorsum of fifth metatarsal base

functions in dorsiflexion and eversion

Question 5

Extends hallux

Answer 5

Extensor Hallucis longus

extend hallux and dorsiflex ankle

anteromedial fibular surface and interosseous membrane

distal: base of phalanx of hallux

Question 6

My distal tendon does not attach to a digit

Answer 6

fibularis tertius

Question 7

(Dorsiflexion/extension of 4 digits)

vs

(Dorsiflexion/eversion)

vs

(extends hallux/dorsiflex ankle)

vs

(dorsiflexion and inversion)

Answer 7

dorsiflexion/extension 4 digits = flexor digitorum longus

dorsiflexion/extension = fibularis tertius

dorsiflexion/inversion = tibialis anterior

dorsiflexion/extension of hallux = extensor hallucis longus

Question 8

Proximal attachments:

(lateral tibial condyle/anterior fibular surface/interosseous membrane)

vs

(lateral tibial condyle and superolateral .5 of tibia)

vs

(anteroinferior fibular surface)

vs

(anteromedial fibular surface and interosseous membrane)

Answer 8

(lateral tibial condyle/anterior fibular surface/interosseous membrane) = extensor digitorum longus

(lateral tibial condyle and superolateral .5 of tibia) = tibialis anterior

(anteroinferior fibular surface) = fibularis tertius

(anteromedial fibular surface and interosseous membrane) =
extensor hallucis longus

Question 9

deep fibular nerve

Answer 9

anterior compartment nerve

supplies:

anterior compartment muscles
ankle joint and metacarpal phalangeal joints
dorsal intrinsic foot muscles
skin between first and second digits

Question 10

anterior compartment artery

Answer 10

arises from popliteal artery

passes anteriorly over interosseous membrane

ends at ankle between malleoli to become dorsalis pedis artery