Foot

Question 1

Name the muscles on the dorsum of the foot

Answer 1

Extensor Digitorum Brevis

Extensor Hallucis Brevis

Question 2

Give the origin, insertion, innervation, action, and test for:

Extensor Digitorum Brevis

Answer 2

Origin:
Calcaneus, interosseous talocalcaneal ligament, stem of inferior extensor retinaculum

Insertion:
Tendons of extensor Digitorum Longus on each of the 4 lateral toes.

Innervation:
Deep Peroneal Nerve (L4,5,S1)

Action:
Assists extensor Digitorum Longus in extending the metatarsophalangeal joints and interphalangeal joints of the lateral 4 toes.

Test:
None listed.

Question 3

Give the origin, insertion, innervation, action, and test for:

Extensor Hallucis Brevis

Answer 3

Origin:
Calcaneus, interosseous talocalcaneal ligament, stem of inferior extensor retinaculum.

Insertion:
Dorsal aspect of base of proximal phalanx in great toe.

Innervation:
Deep Peroneal Nerve (L4,5,S1)

Action:
Aids Extensor Hallucis Longus in extending the metatarsophalangeal joint.

Test:
None listed.

Question 4

Give the muscles in the sole of the foot

Answer 4

Abductor Hallucis
Flexor Digitorum Brevis
Abductor Digiti Minimi
Quadratus Plantae
Lumbricals
Flexor Hallucis Brevis
Adductor Hallucis
Flexor Digiti Minimi Brevis 
Plantar Interossei
Dorsal Interossei

Question 5

Give the muscles in the 1st layer of the sole of the foot

Answer 5

Abductor Hallucis
Flexor Digitorum Brevis
Abductor Digiti Minimi

Question 6

Give the muscles in the 2nd layer of the sole of the foot

Answer 6

Quadratus Plantae

Lumbricals

Question 7

Give the muscles in the 3rd layer of the sole of the foot

Answer 7

Flexor Hallucis Brevis
Adductor Hallucis
Flexor Digiti Minimi Brevis

Question 8

Give the muscles in the 4th layer of the sole of the foot

Answer 8

Plantar Interossei

Dorsal Interossei

Question 9

Give the origin, insertion, innervation, and action for:

Abductor Hallucis

Answer 9

Origin:
Medial tubercle of the calcaneal tuberosity, Flexor Retinaculum, Plantar Aponeurosis

Insertion:
Medial side of base of proximal phalanx of the great toe.

Innervation:
Medial Plantar Nerve (S2,3)

Action:
Abduct and flex the great toe

Question 10

Give the origin, insertion, innervation, and action for:

Flexor Digitorum Brevis

Answer 10

Origin:
Medial tubercle of the calcaneal tuberosity, Plantar aponeurosis, Intermuscular septa

Insertion:
Both sides of the middle phalanges of the 4 lateral toes

Innervation:
Medial Plantar Nerve (S2,3)

Action:
Flexion of the lateral 4 digits (at the metatarsophalangeal joints + proximal interphalangeal joint)

Question 11

Give the origin, insertion, innervation, and action for:

Abductor Digiti Minimi

Answer 11

Origin:
Medial and Lateral tubercles of the tuberosity of calcaneus, plantar aponeurosis, Intermuscular septa.

Insertion:
Lateral side of base of proximal phalanx of Digiti Minimi

Innervation:
Lateral Plantar Nerve (S2,3)

Action:
Abduct and flex the little toe.

Question 12

Give the origin, insertion, innervation, and action for:

Quadratus Plantae

Answer 12

Origin:
Medial surface + Lateral margin of plantar surface of calcaneus

Insertion:
Posterolateral side of flexor Digitorum Longus tendons

Innervation:
Lateral Plantar Nerve (S2,3)

Action:
Assists flexor Digitorum Longus in flexing the lateral 4 digits

Question 13

Give the origin, insertion, innervation, and action for:

Lumbricals

Answer 13

There are 4 of these
Origin:
Tendons of flexor Digitorum Longus

Insertion:
Medial aspect of expansion over lateral 4 digits

Innervation:
Medial 1 = Medial Plantar Nerve (S2,3)
Lateral 3 = Lateral Plantar Nerve (S2,3)

Action:
Flex the proximal phalanges and extend the middle + distal phalanges of the lateral 4 toes.

Question 14

Give the origin, insertion, innervation, and action for:

Flexor Hallucis Brevis

Answer 14

Origin:
Plantar surface of cuboid and lateral cuneiform

Insertion:
Both sides of proximal phalanx of great toe

Innervation:
Medial Plantar Nerve (S2,3)

Action:
Flex great toe at metatarsophalangeal joint

Question 15

Give the origin, insertion, innervation, and action for:

Adductor Hallucis

Answer 15

Origin:
Oblique head = Base of 2nd-4th metatarsals
Transverse head = Plantar ligaments of metatarsophalangeal joints

Insertion:
Both heads insert into lateral side of proximal phalanx of great toe

Innervation:
Deep branch of lateral plantar nerve.

Action:
Adducts the great toe + assists to maintain transverse arch of the foot.

Question 16

Give the origin, insertion, innervation, and action for:

Flexor Digiti Minimi Brevis (Foot)

Answer 16

Origin:
Base of 5th metatarsal

Insertion:
Base of proximal phalange of 5th digit.

Innervation:
Superficial branch of lateral plantar nerve.

Action:
Flexes the proximal phalanx of the 5th digit.

Question 17

Give the origin, insertion, innervation, and action for:

Plantar Interossei

Answer 17

There are 3 of these
Origin:
Medial sides + bases of 3-5th metatarsals

Insertion:
Medial side of bases of phalanges of 3-5th digits

Innervation:
Lateral Plantar Nerve (S2,3)

Action:

• Adducts the 3-5th digits towards the 2nd toe.
• Assists the Lumbricals in flexing the metatarsophalangeal joints and extending the interphalangeal joints.

REMEMBER: For Interossei - PADs and DABs
Plantar = ADduction and Dorsal = ABduction

Question 18

Give the origin, insertion, innervation, and action for:

Dorsal Interossei

Answer 18

There are 4 of these
Origin:
Adjacent sides of all of the metatarsals

Insertion:
1st = Medial side of proximal phalanx of 2nd digit
2-4 = Lateral sides of 2-4th digits

Innervation:
Lateral Plantar Nerve (S2,3)

Action:

• Abduct the 2-4th digits
• Assist the Lumbricals in flexing the metatarsophalangeal joints and extending the interphalangeal joints.

REMEMBER: For Interossei - PADs and DABs
Plantar = ADduction and Dorsal = ABduction