Unit 5 - Lower Limb: Arches of the Foot (Ex. IV)

Question 1

What is the function of the arches?

Answer 1

• weight distribution onto heel and ball of foot
• shock absorbers during locomotion
• enhancement of flexibility of foot when on uneven surfaces

Question 2

Which arch has M and L parts?

Answer 2

longitudinal arch

Question 3

What is the highest part of the longitudinal arch?

Answer 3

M arch

Question 4

What bones form the M longitudinal arch?

Answer 4

talus
navicular
calcaneus
M, L, and intermediate cuneiforms
M metatarsals

Question 5

What is the keystone of the M longitudinal arch?

Answer 5

head of the talus

Question 6

L part of longitudinal arch

Answer 6

flatter than M part

Question 7

What bones form the L part of the longitudinal arch?

Answer 7

calcaneus
cuboid
L metatarsals

Question 8

What bones form the transverse arch?

Answer 8

cuboid
M, L, and intermediate cuneiforms
bases of metatarsals

Question 9

What supports the arches?

Answer 9

active and passive stabilizers

Question 10

primary active stabilizers of the arches (8)

Answer 10

tibialis P (T and L)
fibularis longus (T)
flexor hallucis longus (M)
flexor digitorum brevis (L)
flexor hallucis brevis (L)
abductor hallucis (L)
abductor digiti minimi (L)
adductor hallucis (T and L)

Question 11

primary passive stabilizers of the arches (4)

Answer 11

plantar aponeurosis
plantar calcaneonavicular ligament (spring ligament)
long plantar ligament
plantar calcaneocuboid ligament (short plantar ligament)

Question 12

What is the cause of pes planus (flatfoot)?

Answer 12

both the active and passive stabilizers of the M longitudinal arch are lax or absent
head of talus is not supported –> can displace I-M ==> forefoot everts and abducts - increased stress on plantar calcaneonavicular (spring) ligament

Question 13

Tarsal and metatarsal bones form what?

Answer 13

flexible longitudinal and transverse arches on the sole of the foot