0722 - Anatomy of Foot and Ankle

Question 1

What are the landmarks of the distal fibula? Articulations?

Answer 1

Lateral malleolus and malleolar fossa.

Articulates with distal tibia and talus

Question 2

What are the landmarks of the distal tibia? Articulations?

Answer 2

Medial malleolus and fibular notch.

Articulates with fibula and talus.

Question 3

Describe the talus

Answer 3

Body, neck and head - with neck directed medially.
Head is rounded and ovoid/convex
Articulates - superiorly with tibia, laterally with fibula, inferiorly with calcaneous and navicular.

Question 4

Articulations of the calcaneus

Answer 4

Articulates superiorly with talus, distally with cuboid.

Question 5

Articulations of the Navicular

Answer 5

Articulates distally with cuneiforms, laterally with cuboid.

Question 6

Articulations of the Cuboid

Answer 6

Articulates with lateral cuneiform (medially), calcaneus, and 4 and 5 metatarsals.

Question 7

What are the articulations of the Cuneiforms

Answer 7

Medial, intermediate, lateral articulate with 1, 2, 3 phalanges. Then laterally articulates with cuboid.

Question 8

What are the two important sets of ligaments of the ankle?

Answer 8

Syndesmosis - hold tibia and fibula together, consisting of anterior inferior, posterior inferior tibio-fibular ligaments and interosseous membrane. Can seriously injure if foot turns up and sole laterally.
Lateral ankle ligaments - Anterior talo-fibilar ligament (simple sprain), calcaneofibular ligament, posterior tibio-fibular ligament (sprained ankle)

Question 9

Describe gastrocnemius (O,I,N,A)

Answer 9

Origin - medial and lateral condyles of femur
Insertion - becomes achilles tendon - posterior surface of calcaneus
Innervation - Tibial Nerve (S1-2)
Action - Plantar flexion of the ankle.

Question 10

Describe soleus (OINA)

Answer 10

Origin - Soleal line on posterior tibia and upper posterior of fibular.
Insertion - Joins with gastrocnemius to become achilles - posterior surface of calcaneus
Innervation - Tibial nerve (S1-2)
Action - Plantar flexion of ankle.

Question 11

Tibialis Anterior (OINA)

Answer 11

O - Lateral condyle and proximal 1/2 of lat surface of tibia, interosseous membrane
Insertion - medial and plantar surface of medial cuneiform bone, base of first metatarsal
Innervation - Peroneal nerve (L4-5)
Action - Dorsiflexion of ankle, inversion of foot.

Question 12

Extensor hallucis Longus (OINA)

Answer 12

O - Middle half of anterior surface of fibula and adjacent interosseous membrane.
I - Dorsal distal phalanx of hallux.
N - Peroneal nerve (L4-5)
A - Extension of Hallux

Question 13

Extensor digitorum Longus (OINA)

Answer 13

O- Lateral condyle and upper shaft of tibia.
I - Distal phalanges of digits 2-5.
N - Peroneal nerve
A - Extends interphalangeal joints.

Question 14

Why is Peroneus Brevis important?

Answer 14

Important because it runs behind lateral malleolus, insert into base of 5th metatarsal.

Question 15

Peroneus Longus

Answer 15

O - Head and proximal lateral fibula
I - Lateral side of base of first metatarsal and medial cuneiform.
N - Peroneal nerve (L5-S1)
A - Eversion of the foot, assist in plantar flexion of ankle.

Question 16

Tibialis Posterior

Answer 16

Deep muscle
O - Interosseous membrane, posterior tibia and upper fibula.
I - Navicular tuberosity, cuneiforms, cuboid, metatarsals 2-4
N - Tibial nerve
A - Plantar flexion of foot.

Question 17

Flexor Hallucis Longus

Answer 17

O - Post surface of distal fibula and interosseous membrane.
I - Plantar surface of base, distal phalanx of hallux
N - Tibial Nerve
Action - Flexion of distal phalanx of hallux.

Question 18

Flexor digitorum longus

Answer 18

O - Middle of posterior border of tibia, and fascia of tib posterior
I - Plantar surface, base of distal phalanges 2-5
N - Tibial nerve
A - Flexion of interphalangeal and metatarsophalangeal joints toes 2-5

Question 19

Outline the Long plantar ligament

Answer 19

Takes tension in arch during support of body weight

Arises from plantar aspect of calcaneus. Expands and splits into 5 digital slips going to plantar aspects of toes.

Question 20

Outline the Bifurcate ligament

Answer 20

Origin - Upper part of calcaneus
Insertion - Cuboid and navicular
May lead to an avulsion fracture - it never ruptures but can fracture.

Question 21

What is the vascular supply of the ankle?

Answer 21

Popliteal artery splits into ant. and post. tibial arteries.
Posterior tibial artery supplies posterior muscles of leg. Passes behind medial malleolus to plantar aspect, forming med and lat. plantar arteries.
Peroneal artery runs off post. tibial. and supplies lateral muscles.
Anterior tibial runs down interosseous membrane, supplying extensor muscles. Reaches dorsum of foot as dorsalis pedis artery.

Question 22

What is the nerve supply of the ankle?

Answer 22

Sciatic n splits into tibial and common peroneal above the knee.
Tibial nerve - continuation of sciatic nerve. Supplies major muscles of posterior leg.
Common peroneal nerve becomes superficial and deep - deep supplies dorsiflexors of ankle, superficial supplies everters of foot (peroneus longus and brevis)