Foot Musculature (1st and 2nd Layer)

Question 1

Abductor hallucis

Answer 1

Origin:
- Medial process of calcaneus
- Plantar aponeurosis
Insertion:
- Medial side of base of proximal phalanx of big toe
Action:
- Flexes big toe
- May assist to abduct big toe
Nerve:
- Medial plantar 
- L5, S1

Question 2

Flexor digitorum brevis

Answer 2

Origin:
- Anterior aspect of medial process of calcaneus
- Plantar aponeurosis
Insertion:
- Splits to attach on both sides of the middle phalanx of toes 2-5
Action:
- Flexes toes 2-5
Nerve:
- Medial plantar 
- L5, S1

Question 3

Abductor digiti minimi

Answer 3

Origin:
- Lateral process of calcaneus
- Plantar aponeurosis
Insertion:
- Lateral side of the base of the proximal phalanx of the 5th toe
Action:
- Abducts 5th toe
- Assists to flex 5th toe
Nerve:
- Lateral plantar 
- L5, S1

Question 4

Quadratus Plantae

Answer 4

Origin:
- Medial head: medial calcaneus
- Lateral head: lateral calcaneus and long plantar ligament
Insertion:
- Lateral edge of tendon of flexor digitorum longus
Action:
- Aids to flex toes 2-5 by offsetting the oblique pull of the FDL
Nerve:
- Lateral plantar
- S1, S2

Question 5

Lumbricales

Answer 5

Origin:
- From the tendon of the flexor digitorum longus (4 muscles)
Insertion:
- Onto tendons of extensor digitorum longus
Action:
- Flexes proximal phalanx at MTP joint of toes 2-5
- Extends toes 2-5 at IP joints
Nerve:
- 1st: medial plantar
- 2nd – 4th: lateral plantar