Week 3 - Ankle and Foot

Question 1

Describe the talocrural joint

Answer 1

The upper surface of the talus articulates with the tibiofibular mortise - the distal Tibial and fibular syndesmosis, that acts like a clamp over the talus

Question 2

Where are the articulating areas of the talus?

Answer 2

Anteriorly - when in dorsiflexion
On either side for the malleoli
On the upper surface for T+F
Anteriorly - with navicualr bone

Question 3

Where are the collateral ligaments of the ankle?

Answer 3

One at fibular

One at tibial

Question 4

Describe the tibial collateral ligament

Answer 4

This is the deltoid ligament, it’s thicker and stronger than the fibial collateral ligament
Attaches to medial malleolus, merges with spring ligament in the foot

Question 5

Describe the talus bone

Answer 5

Round head with a block-like body, sits partly on top of calcaneus

Question 6

Describe the shape of the navicular bone, and where it sits in the foot

Answer 6

• Navicular bone is slightly boat shaped, and is located on the medial side of the foot
• It articulates proximally with the talus, distally with the three cuneiform bones and laterally with the cuboid bone
• It is part of the medial longitudinal arch and the transverse tarsal joint –> two structures that are essential for normal gait

Question 7

Which bone does the cuboid articulate proximally with?

Answer 7

The calcaneus

Question 8

Which bones fill the medial gap between the navicular bone and the cuboid bone?

Answer 8

The three cuneiform bones - medial, intermediate and lateral

Question 9

What are the three joints that the talus is involved in?

Answer 9

Talocrural - talus + tibia + fibula
Talonavicular joint - talus + navicular bone
Talocalcaneal/subtalar joint - talus + calcaneal bone

Question 10

Which part of the calcaneal supports the talus?

Answer 10

The Sustentaculum Tali - a shelf on the calcaneus

Question 11

Describe the three areas of articulation in the talocalcaneal joint

Answer 11

These are the anterior, middle and posterior facets. The sustentaculum tali forms the floor of middle facet, and the anterior facet articulates with the head of the talus, and sits lateral and congruent to the middle facet.
The posterior facet is the largest of the three, and separated from the others by the tarsal canal.

Question 12

What type of joint is the talonavicular joint?

Answer 12

A synovial

Question 13

Describe the plantar calcaneonavicular ligament

Answer 13

• This is the spring ligament
• This very strong ligament is on the planar side of the foot and connects the calcaneus at the sustentaculum tali to the navicular bone

Question 14

What does the spring ligament do with the talus?

Answer 14

-It’s so strong that is able to support the head of the talus, forming part of an articular cavity with the talus, and preventing the talus curved head from flattening out. does not allow the curved head of the talus to flatten out

Question 15

What is the major role of the spring ligament?

Answer 15

To maintain the medial longitudinal arch of the foot, and by providing support to the head of the talus, bear the major portion of the body weight.

Question 16

Describe the talocalcaneonavicular joint

Answer 16

This is a ball and socket joint made up of the rounded head of the talus being received by the concavity formed by the posterior region of the navicular bone, the anterior articular surface of the calcaneus and the upper surface of the plantar calcaneonavicular (spring) ligament

Question 17

Which muscles allow inversion of the foot?

Answer 17

The medial muscles: includes tibialis anterior + tibialis posterior, as well as flexor digitorum and flexor hallucis longus

Question 18

Which muscles evert the foot?

Answer 18

Lateral muscles: includes the fibular/peroneal muscles

Question 19

Which are the medial bones of the foot?

Answer 19

Talus
Navicular
Cuneiform bones
Metatarsal 1

Question 20

Which are the lateral bones of the foot?

Answer 20

Calcaneus
Cuboid
Metatarsal 5

Question 21

Where does the reference line of the foot run through?

Answer 21

M2

Question 22

Which muscles are attached to the talus?

Answer 22

NONE

Question 23

Which are the two deep, lateral muscles of the foot? Where do they attach?

Answer 23

Fibularis longus - attaches to M1, crossing the sole of the foot
Fibularis brevis - attaches to M5, merging off F-longus

Question 24

Which are the two thick tendons of the medial side of the foot? Where do they attach?

Answer 24

Tibialis anterior, attaches to M1

Tibialis posterior - attaches mainly to the navicular bone, but has some slip to other bones

Question 25

Which are the two ligaments between the lateral and medial tendons of the foot?

Answer 25

``` Plantar calcaneonavicular (spring) ligament is medial and close to tibialis posterior Short plantar ligament is closer to the lateral side, and connects the calcaneus to the cuboid ```

Question 26

Do plantar interossei muscles of the foot abduct or adduct?

Answer 26

Adduct

Question 27

Do dorsal interossei muscles of the foot abduct or adduct?

Answer 27

Abduct

Question 28

Describe the dorsal interossei muscles of the foot

Answer 28

Bi-pennate muscles (two heads), feather in shape. Attached to two tarsal bones, so the little toe does not have one attached to the phalanx Second toe has two as this toe is the centre of reference --> there are four of these in total, as the big toe also has none

Question 29

Describe the plantar interossei muscles of the foot

Answer 29

More slender than the dorsal interossei muscles, with only one head. These adduct the phalanges

Question 30

Which ligament covers the fibularis longus tendon?

Answer 30

The long plantar ligament

Question 31

Which toes have short flexors?

Answer 31

The little toe and the big toe

Question 32

What are the two short flexors of the toes?

Answer 32

Flexor hallucis brevis | Flexor digiti minimi

Question 33

Where does flexor hallucis brevis arise originate and attach?

Answer 33

This muscle originates from the undersurface of the cuboidal bone via a tendinous process It splits into two attachments - one to the medial and one to the lateral base of the 1st phalanx (big toe)

Question 34

Describe the origin and attachment of flexor digiti minimi

Answer 34

Originates from M5, attaches to the base of the 5th phalanx

Question 35

Describe adductor hallucis

Answer 35

This is a two headed muscle responsible for adducting the big toe The oblique head arises from the bases of the second, third, and fourth metatarsal bones, attaching to the lateral side of the base of the 1st phalanx The transverse head arises from the bases of the 3rd, 4th and 5th phalanges, inserting at the same point as the oblique head

Question 36

Describe flexor digitorum longus, and its orientation in the foot

Answer 36

Origin is more medial than flexor hallucis longus Crosses the foot laterally and reaches the distal phalanges Made up of four tendons, attached to which are the four lumbricals of the foot (in metatarsal region)

Question 37

What action would flexor digitorum longus perform in the foot?

Answer 37

Tends to pull toe medially because it crosses the sole from medial to lateral

Question 38

What corrects the additional action of FDL?

Answer 38

An accessory muscle called flexor accessorius/quadratus plantae

Question 39

Describe abductor hallucis

Answer 39

Attached to calcaneum and the medial side of the base of the 1st proximal phalanx by a long thin tendon

Question 40

Describe abductor digiti minimi

Answer 40

Attached to calcaneum and the lateral base of the 5th proximal phalanx

Question 41

Why is flexor digitorum brevis comparable to flexor digitorum superficialis in the forearm?

Answer 41

It also has split tendons, splitting at the middle phalanx and attaching there, while Flexor Digitorum longus continues through the split to the distal phalanx. This is the same situation as in the hand with FDS and FDP

Question 42

What are the two bony arches of the foot?

Answer 42

Longitudinal | Transverse

Question 43

What maintains the bony arches of the foot?

Answer 43

Long intrinsic muscles Extrinsic tendons: TA+TP, FL + FB --> these form a 'sling' around the foot Ligaments: PCN and 2x Plantar

Question 44

Which nerves innervate the sole of the foot?

Answer 44

The tibial nerve

Question 45

What are the muscles on the dorsum side of the foot?

Answer 45

Extensor hallucis brevis | Extensor digitorum brevis

Question 46

What and where is the key piece of fascia in the foot?

Answer 46

This is the plantar aponeurosis and is found from the tuberosity of the calcaneus to the heads of the metatarsal bones It supports the plantar arch of the foot

Question 47

Where would you find the posterior tibial nerve before it split's into three branches?

Answer 47

It crosses the ankle behind the medial malleolus

Question 48

What are the three branches of the posterior tibial nerve? What do they innervate?

Answer 48

Medial calcaneal nerve - sensory innervation of the heel Medial plantar nerve - sensory perception of bottom of big toes, 2nd and 3rd toes + 1/2 of 4th toe. Also medial 2/3s of bottom of the foot. Lateral plantar nerve - sensory perception to outside 1/3 of bottom of foot, and 1/2 4th toe +5th tpe

Question 49

Where would you find the deep peroneal/anterior tibial nerve at the snkle?

Answer 49

Passes down the front of the ankle before dividing into medial and lateral branches

Question 50

What does the medial branch of the anterior tibial nerve innervate?

Answer 50

1st toe web

Question 51

What does the lateral branch of the anterior tibial nerve innervate?

Answer 51

Extensor digitorum brevis, then nervous input to 2nd, 3rd and 4th interosseous muscles