Gross Anatomy- Arches of the Foot

Question 1

What are the two Arches of the Foot and name the functions?

Answer 1

Longitudinal Arch

Transverse Arch

Function:

• Numerous bones and ligaments allow for shock absorption
• Tarsal and metatarsal bones arranged into arches
o Adds to weight-bearing capabilities and resiliency
• Arches act as shock absorbers and springboards
• Add to foot’s ability to adapt to changes in surface contour
• Become slightly flattened when standing
o Resume curvature when body weight is removed

Question 2

Describe the **Longitudinal Arch **

Answer 2

• Composed of two parts:

Medial part

Lateral part

• Functionally act as a unit with transverse arch, dispersing weight in all directions
• Dynamic support for both parts provided by:
o Active (reflexive) bracing by intrinsic mm.
o Active and tonic contractions of:
 Flexor hallucis longus and flexor digitorum longus tt.

Question 3

Decribe the Medial Part of the Longitudinal Arch and what structures make it up

Answer 3

• Medial - calcaneus, talus, navicular, 3 cuneiforms and metatarsals 1-3
o High and mobile arch
o More important than lateral longitudinal arch
o Primarily weight-bearing
o Bony keystone – talar head
o Muscular keystone – tibialis posterior m.
o Ligamentous keystone – plantar calcaneonavicular (spring) l.
o Ligaments –
 Plantar calcaneonavicular l.
 Plantar aponeurosis

o Suspension from above –
 Tibialis anterior m.
 Fibularis longus t.
 Deltoid

Question 4

Describe the Lateral Part of the Longitudinal Arch and what structures make it up

Answer 4

• Lateral – involves calcaneus, cuboid and 4th-5th metatarsals
o Flatter and less mobile
o Primarily for balance
o Keystone - cuboid

o Ligaments –
 Long and short plantar ll.
 Plantar aponeurosis

o Muscular support–
 Flexor digitorum longus m.
 Abductor digiti minimi m.

o Suspension from above –
 Fibularis longus m.
 Fibularis brevis m.

Question 5

Describe the Transverse Arch and what structures make this arch

Answer 5

• Runs from side to side
• Formed by cuboid, 3 cuneiforms, base of metatarsals 1-5
• Medial and lateral longitudinal arches act as pillars
• Shape of united bones most important for this arch

Question 6

Name the Ligaments of the Transverse Arch

Answer 6

o Ligaments –

 Dorsal and plantar intertarsal ll.
 Plantar aponeurosis

Question 7

What muscles support the Transverse Arch of the Foot?

Answer 7

o Muscular support -
 Fibularis longus t.
 Tibialis posterior t.
 Adductor hallucis m. (transverse head)

Question 8

What is the condition of Pes Planus (Flatfeet)?

Answer 8

Disappearance of medial longitudinal arch

Question 9

What are the 3 types of Pes Planus (Flatfeet)?

Answer 9

Flexible flatfeet

Rigid flatfeet:

Acquired flatfeet:

Question 10

Describe characteristics of Flexible flatfeet

Answer 10

o Most common type
o Lack medial longitudinal arch when standing
o Arch reappears when not weight-bearing
o Results from loose or degenerated intrinsic ll.
o Common in children
o May persist into adulthood

Question 11

Describe characteristics of Rigid Flatfeet.

Answer 11

o Flat even when not bearing weight
o Likely results from bone deformity
 Fusion of adjacent tarsals

Question 12

Desribe the characteristics of Aquired flatfeet

Answer 12

o “Fallen arches”
o Secondary to dysfunction of tibialis posterior (dynamic support)
 Trauma
 Degeneration with age
 Denervation
o Plantarcalcaneonavicular l. fails to support talar head
 Displaces inferomedially and becomes prominent
 Results in flattening of medial longitudinal arch and lateral deviation of forefoot