Sole of the Foot

Which muscles compose the first (superficial) layer?

Abductor hallicus, flexor digitorum brevis, abductor digiti minimi

Abductor hallicus origin

Calcaneal tuberosity, flexor retinaculum, plantar aponeurosis

Abductor hallicus insertion

Medial side of proximal phalanx of great toe

Abductor hallicus action

Abduct great toe

Abductor hallicus innervation

Medial plantar nerve

Flexor digitorum brevis origin

Calcaneal tuberosity, plantar aponeurosis

Flexor digitorum brevis insertion

Middle phalanges of lateral 4 digits

Flexor digitorum brevis action

Flex lateral 4 digits

Flexor digitorum brevis innervation

Medial plantar nerve

Abductor digiti minimi origin

Calcaneal tuberosity, plantar aponeurosis

Abductor digiti minimi insertion

Lateral side of proximal phalanx of little toe

Abductor digiti minimi action

Abduct little toe

Abductor digiti minimi innervation

Lateral plantar nerve

Which muscles compose the second (second most superficial) layer?

Quadratus plantae and lumbricals

Quadratus plantae origin

Calcaneus

Quadratus plantae insertion

Flexor digitorum longus tendon

Quadratus plantae action

Assists with flexion of lateral 4 toes

Quadratus plantae innervation

Lateral plantar nerve

Lumbricals origin

Tendons of flexor digitorum longus

Lumbricals insertion

Extensor expansions of lateral 4 digits

Lumbricals action

Flex MTP joints, extend proximal and distal IP joints of lateral 4 digits

Lumbricals innervation

1 medial plantar nerve, 2-4 lateral plantar nerve

Which muscles compose the 3rd (second deepest) layer?

Flexor hallicus brevis, adductor hallicus, flexor digiti minimi brevis

Flexor hallicus brevis origin

Cuboid, lateral cuneiform

Flexor hallicus brevis insertion

Base of proximal phalanx of great toe

Flexor hallicus brevis action

Flex PIP joint of great toe

Flexor hallicus brevis innervation

Medial plantar nerve

Adductor hallicus oblique head origin

Bases of metatarsals 2-4

Adductor hallicus transverse head origin

Plantar ligaments of MTP joints

Adductor hallicus insertion

Base of proximal phalanx of great toe

Adductor hallicus action

Adducts great toe, maintains transverse arch

Adductor hallicus innervation

Deep branch of lateral plantar nerve

Flexor digiti minimi brevis origin

Base of metatarsal 5

Flexor digiti minimi brevis insertion

Base of proximal phalanx of little toe

Flexor digiti minimi brevis action

Flex PIP of little toe

Flexor digiti minimi brevis innervation

Superficial branch of lateral plantar nerve

Which muscles compose the 4th (deepest) layer?

Plantar and dorsal interossei

Plantar interossei origin

Medial sides of metatarsals 3-5

Plantar interossei insertion

Medial sides of proximal phalanges 3-5

Plantar interossei action

Adduct digits 3-5

Dorsal interossei origin

Adjacent sides of metatarsals 1-5

1st dorsal interosseus insertion

Medial side of proximal phalanx of 2nd digit

Interossei 2-4 insertion

Lateral sides of digits 2-4

Dorsal interossei action

Abduct digits 2-4

Common innervation for dorsal and plantar interossei

Lateral plantar nerve

How many plantar interossei are there?

3

How many dorsal interossei are there?

4