Plantar Intrinsic Muscles of the Foot

Question 1

Muscles in First (Superficial) plantar layer

Answer 1

Flexor Digitorum Brevis
Abductor Hallucis
Abductor Digiti Minimi

Question 2

Origin of Flexor Digitorum Brevis

Answer 2

Medial process of Calcaneal Tuberosity

Plantar Aponeurosis

Question 3

Insertion of Flexor Digitorum Brevis

Answer 3

Middle Phalanges of Toes 2-5

Question 4

Innervation of Flexor Digitorum Brevis

Answer 4

Medial Plantar Nerve (S1-S3)

Question 5

Function of Flexor Digitorum Brevis

Answer 5

Flexion of Toes 2-5 at Proximal Interphalangeal Joint

Question 6

Origin of Abductor Hallucis

Answer 6

Medial Process of Calcaneal Tuberosity

Question 7

Insertion of Abductor Hallucis

Answer 7

Proximal Phalanx of Toe 1

Question 8

Innervation of Abductor Hallucis

Answer 8

Medial Plantar Nerve (S1-S3)

Question 9

Function of Abductor Hallucis

Answer 9

Abduction and flexion of Toe 1 at MTP joint

Question 10

Origin of Abductor Digiti Minimi

Answer 10

Lateral and medial processes of Calcaneal Tuberosity

Connective Tissue between CT and Metatarsal 5

Question 11

Insertion of Abductor Digiti Minimi

Answer 11

Proximal Phalanx of Toe 5

Question 12

Innervation of Abductor Digiti Minimi

Answer 12

Lateral Plantar Nerve (S1-S3)

Question 13

Function of Abductor Digiti Minimi

Answer 13

Abduction of Toe 5 at MTP joint

Question 14

Muscles in second plantar layer

Answer 14

Quadratus Plantae

Lumbricals x4

Question 15

Origin of Quadratus Plantae

Answer 15

Medial Calcaneus

Lateral Calcaneal Tuberosity

Question 16

Insertion of Quadratus Plantae

Answer 16

Flexor Digitorum Longus tendon

Question 17

Innervation of Quadratus Plantae

Answer 17

Lateral Plantar Nerve (S1-S3)

Question 18

Function of Quadratus Plantae

Answer 18

Flexion of Toes 2-5

assists Flexor Digitorum Longus

Question 19

Origin of Lumbricals

Answer 19

Medial Tendon of FDL to Toe 1 (1st Lumbrical)

Adjacent FDL tendons of Toes 2-4 (Lumbricals 2-4)

Question 20

Insertion of Lumbricals

Answer 20

Extensor Hoods of Toes 2-5

Question 21

Innervation of Lumbricals

Answer 21

Medial Plantar Nerve (Lumbrical 1)

Lateral Plantar Nerve (Lumbricals 2-4)

Question 22

Function of Lumbricals

Answer 22

Flexion of MTP and extension of interphalangeal joints

similar to hand lumbricals

Question 23

Muscles in Third Intrinsic layer

Answer 23

Flexor Hallucis Brevis
Flexor Digiti Minimi Brevis
Adductor Hallucis

Question 24

Origin of Flexor Hallucis Brevis

Answer 24

Cuboid and Lateral Cuneiform

Tibialis Posterior Tendon

Question 25

Insertion of Flexor Hallucis Brevis

Answer 25

Proxmial Phalanx of Toe 1 (lateral and medial sides as two heads)

Question 26

Innervation of Flexor Hallucis Brevis

Answer 26

Medial Plantar Nerve (S1-S2)

Question 27

Function of Flexor Hallucis Brevis

Answer 27

Flexes Toe 1 at MTP joint

Question 28

Origin of Adductor Hallucis

Answer 28

TRANSVERSE HEAD: Metatarsophalangeal Ligaments of Toes 3-5 OBLIQUE HEAD: Base of Metatarsals 2-4, sheath covering fibularis longus

Question 29

Insertion of Adductor Hallucis

Answer 29

Proximal Phalanx of Toe 1

Question 30

Innervation of Adductor Hallucis

Answer 30

Lateral Plantar Nerve (S2-S3)

Question 31

Function of Adductor Hallucis

Answer 31

Adducts Toe 1 at MTP joint

Question 32

Origin of Flexor Digiti Minimi Brevis

Answer 32

Base of Metacarpal 5 Sheath of Fibularis Longus Tendon

Question 33

Insertion of Flexor Digiti Minimi Brevis

Answer 33

Proximal Phalanx of Toe 5

Question 34

Innervation of Flexor Digiti Minimi Brevis

Answer 34

Lateral Plantar Nerve

Question 35

Function of Flexor Digiti Minimi Brevis

Answer 35

Flexion of Toe 5 at MTP joint

Question 36

Muscles in Fourth (deepest) Intrinsic layer

Answer 36

4x Dorsal Interossei | 3x Palmar Interossei

Question 37

Origin of Dorsal Interossei

Answer 37

Sides of Adjacent Metatarsals

Question 38

Insertion of Dorsal Interossei

Answer 38

Proximal Phalanges/Extensor Hoods of Toes 2-5

Question 39

Innervation of Dorsal Interossei

Answer 39

Lateral Plantar Nerve | Dorsal interossei 1 and 2 are also innervated by the Deep Fibular Nerve

Question 40

Function of Dorsal Interossei

Answer 40

Abduction (DAB) | of Toes 2-5

Question 41

Origin of Plantar Interossei

Answer 41

Metatarsals 3-5

Question 42

Insertion of Plantar Interossei

Answer 42

Proximal Phalanges/Extensor Hoods of Toes 3-5

Question 43

Innervation of Plantar Interossei

Answer 43

Lateral Plantar Nerve (S2-S3)

Question 44

Function of Plantar Interossei

Answer 44

Adduction (PAD) of Toes 3-5

Question 45

So which 4 plantar muscles are innervated by the Medial Plantar Nerve (all the rest are innervated by Lateral Plantar Nerve)

Answer 45

Flexor Digitorum Brevis (1st Layer) Abductor Hallucis (1st Layer) Lumbrical 1 (2nd Layer) Flexor Hallucis Brevis (3rd Layer)