The Anterior and Lateral Leg

Question 1

Describe the fibularis longus:

Answer 1

Part of the lateral leg
Originates from the head and the upper 2/3 of lateral surface of the fibula
Pass posterior to lateral malleolus
Runs under the foot and inserts on the medial cuneiform and the base of the first metatarsal
Function - foot eversion and plantar flexion
Innervated by the superficial fibular nerve
Blood supply - branches of fibular artery
Largest muscle in lateral leg

Question 2

Describe the fibularis brevis

Answer 2

Originates from the lower 2/3 of the lateral surface of the fibula
Pass posterior to lateral malleolus
lies deep to the fibularis longus
Inserts onto the tuberosity of the fifth metatarsal
Function - foot eversion + plantar flexion
Innervated by the superficial fibular nerve
Blood supply - branches of fibular artery

Question 3

What muscles make up the anterior leg ?

Answer 3

“FEET” lateral to medial
Fibularis tertius
Extensor digitorum longus
Extensor hallucis longus
Tibialis anterior
All innervated by deep fibular nerve and blood supply is anterior tibial artery

Question 4

Describe the Fibularis tertius:

Answer 4

Origin - anterior surface of fibula and adjacent interosseous membrane
Insertion - dorsal surface of the base of the fifth metatarsal
Function - dorsiflexion and eversion (turning the sole of the foot outward)
Passes anterior to lateral malleolus

Question 5

Describe the Extensor digitorum longus:

Answer 5

Originates from anterior surface of fibula, lateral condyle of the tibia and interosseous membrane which separates tibia and fibula
Insertion - phalanges of digits 2-4
Function - Dorsiflex, Extend digits 2-4

Question 6

Describe the Extensor hallucis longus:

Answer 6

Origin - anterior surface of fibula and interosseous membrane
Insertion - dorsal aspect of the base of the distal phalanx of the hallux
Function - extend hallux and dorsiflexion

Question 7

Describe the Tibialis anterior

Answer 7

Origin - tibia and interosseous membrane
Insertion - medial cuneiform bone and the base of the first metatarsal bone on the plantar surface
Function - dorsiflexion and inversion

Question 8

Describe the tibial nerve in the leg:

Answer 8

Located - under soleal arch between 2 layers of posterior compartment
Divides into medial and lateral plantar nerves

Question 9

Describe the common fibular nerve in the leg:

Answer 9

Wraps around head of fibula deep to fibularis longus
Divides into
- superficial fibular nerve supplying lateral leg & dorsum of foot
- deep fibular nerve supplies anterior

Question 10

Describe the posterior tibial artery:

Answer 10

Starts at popliteal artery
At medial malleolus divides into medial and plantar arteries supplying the foot

Question 11

Describe the anterior tibial artery:

Answer 11

Passes through superior part of interosseous membrane
Runs between tibialis anterior and extensor digitorum longus
Passes ankle joint & changes name to dorsal artery of the foot