2 Intrinsic Muscles - FOURTH Layer

Question 1

NAME THE 2 INTRINSIC MUSCLES OF THE FOURTH LAYER

Answer 1

Interossei Dorsal (4)
Plantar (3)

Question 2

Interossei Dorsal (4)

Origin
Insertion

Action

Nerve Supply

Answer 2

Origin: Adjacent sides of metatarsal bones

Insertion: Bases of proximal phalanges – first medial side 2nd toe; remainder lateral sides 2nd, 3rd and 4th toes – also dorsal extensor expansion

Action: Abduction to toes; flexes metatarsophalangeal joints and extends interphalangeal joints

Nerve Supply: Lateral plantar nerve

Question 3

Plantar (3)

Origin
Insertion

Action

Nerve Supply

Answer 3

Origin: Inferior surfaces of 3rd, 4th and 5th metatarsal bones

Insertion: Medial side of bases of proximal phalanges of lateral 3 toes

Action: Adduction of toes; flexes metatarsophalangeal joints and extends interphalangeal
joints

Nerve Supply: Lateral plantar nerve

Question 4

Origin: Inferior surfaces of 3rd, 4th and 5th metatarsal bones

Answer 4

Plantar (3)

Question 5

Insertion: Medial side of bases of proximal phalanges of lateral 3 toes

Answer 5

Plantar (3)

Question 6

Action: Adduction of toes; flexes metatarsophalangeal joints and extends interphalangeal
joints

Answer 6

Plantar (3)

Question 7

Origin: Adjacent sides of metatarsal bones

Answer 7

Interossei Dorsal (4)

Question 8

Insertion: Bases of proximal phalanges – first medial side 2nd toe; remainder lateral sides 2nd, 3rd and 4th toes – also dorsal extensor expansion

Answer 8

Interossei Dorsal (4)

Question 9

Action: Abduction to toes; flexes metatarsophalangeal joints and extends interphalangeal joints

Answer 9

Interossei Dorsal (4)