Lower leg and foot: Foot arthrology

Question 1

What are the 4 functions of the foot?

Answer 1

• Base of support
• Adapt to uneven surfaces
• Shock absorber
  All 3 of these need to be able to absorb stress and it needs to be flexible
• Propulsion
  This requires foot to be rigid (stress transmission)

Question 2

What are the 3 main foot arches?

Answer 2

Medial Arch (highest arch, no contact with the ground, flexible)
Lateral Arch (flatter than medial arch, in contact with ground, more rigid than medial arch)
Anterior Transverse Arch (relatively flat, contacts ground)

Question 3

What is the area supported by the 3 arches called and what are its 3 contact points to the ground?

Answer 3

Plantar Vault (functional middle section of foot) Contacts ground at 3 points:
 A= Head Metatarsal I
 B= Head Metatarsal V
 C= Calcaneal Tuberosity

Question 4

What 5 bones is the Medial Arch of the foot made from?

Answer 4

o Calcaneus (Ca)
o Talus (T)
o Navicular (N)
o Medial cuneiform (Cun)
o Metatarsal I (MT1)

Question 5

What 3 bones is the Lateral Arch of the foot made from?

Answer 5

o Calcaneus (Ca)
o Cuboid (Cu)
o Metatarsal 5 (MT5)

Question 6

What bones are the Anterior Transverse Arch of the foot made from?

Answer 6

Formed by heads of 5 metatarsals

Question 7

What stabilises an arch?

Answer 7

Shapes of bones
Strength of support

Question 8

How do the shapes of bones stabilise an arch?

Answer 8

Wedge-shaped bones interlock, keeping them together.
This relies on top ‘keystone’ for support

Question 9

Strength of support - There are 3 types of support. Name and explain each Support Type.

Answer 9

 Support Type 1 – ‘Staples’ (Bones bound together underneath to prevent them being separated by weight)
 Support Type 2 – ‘Tie Beam’ (Connects 2 end of the arch and prevents separation when weightbearing) (Plantar Fascia)
 Support Type 3 – ‘Sling/Suspension’ (Arch supported from above by cable) (Peroneus Longus)

Question 10

What are the 4 ‘stages’ of walking?

Answer 10

Heel strike
Stance phase
Heel off
Toe off

Question 11

During heel strike, what bone is the weight through and what are the arches doing?

Answer 11

o Weight is through calcaneus
o Arches are raised

Question 12

During stance phase, what happens to the vault and what do the muscles do?

Answer 12

o Vault is flattened – shock absorption
o Muscles contract to stop further flattening: ‘Plantar Tighteners’

Question 13

During heel off, what do plantar tighteners do?

Answer 13

Plantar tighteners contract further

Question 14

During toe off, what happens when big toe extends (what is the mechanism called?)

Answer 14

As big toe extends, plantar fascia tightens, reinforcing medial arch – ‘Windlass Mechanism’

Question 15

What 2 movements can occur when the foot is OFF the floor?

Answer 15

Inversion and Eversion

Question 16

What 3 movements occur during inversion?

Answer 16

Plantarflexion, Adduction, Supination

Question 17

What 3 movements occur during eversion?

Answer 17

Dorsiflexion, Abduction, Pronation

Question 18

What joint does movement occur at at the Hindfoot?

Answer 18

Subtalar Joint (between Calcaneus and Talus)

Question 19

What joint does movement occur at at the Forefoot?

Answer 19

Midtarsal Joint (2 joints in 1)

Question 20

What are the two joints that make up the Midtarsal Joint?

Answer 20

Talonavicular joint (between Talus and Navicular)
Calcaneocuboid joint (between Calcaneus and Cuboid)

Question 21

What 2 movements occur when the foot is ON the floor?

Answer 21

Pronation and Supination

Question 22

What is the difference between ‘Inversion and Eversion’ and ‘Pronation and Supernation’?

Answer 22

 During Inversion and Eversion, the forefoot and hindfoot are moving in the same direction, doing the same thing
 Pronation and Supination, in order for foot to stay on floor, when forefoot rolls in, hindfoot has to stay out and vice-versa (move in opposite directions)

Question 23

What movements occur at Hindfoot during pronation? (See table in document for image)

Answer 23

Adduction, Pronation, Plantarflexion

Question 24

What movements occur at Forefoot during pronation? (See table in document for image)

Answer 24

Abduction, Supination, Dorsiflexion

Question 25

What movements occur at Hindfoot during supination? (See table in document for image)

Answer 25

Abduction, Supination, Dorsiflexion

Question 26

What movements occur at Forefoot during supination? (See table in document for image)

Answer 26

Adduction, Pronation, Plantarflexion