Muscles 77-101

Tibialis anterior origin

Lateral condyle of tibia

lateral surface of tibia and interosseous membrane

Tibialis anterior insertion

Medial cuneiform and base of the 1st metatarsal

Tibialis anterior action

Dorsiflexes ankle joint

inverts subtalar joint

supports medial longitudinal arch of foot

Tibialis anterior innervation

Deep fibular nerve (L4, L5)

Extensor hallucis longus origin

Middle, anterior surface of fibula and interosseous membrane

Extensor hallucis longus insertion

Distal phalanx of 1st toe

Extensor hallucis longus action

Extends great toe

dorsiflexes ankle joint

Extensor hallucis longus innervation

Deep fibular nerve (L5, S1)

Extensor digitorum longus origin

Lateral condyle of tibia

proximal, anterior shaft of fibula and interosseous membrane

Extensor digitorum longus insertion

Middle and distal phalanges of toes 2-5

Extensor digitorum longus action

Extends digits 2-5

dorsiflexes ankle joint

Extensor digitorum longus innervation

Deep fibular nerve (L5, S1)

Fibularis tertius origin

Inferior anterior surface of fibula and interosseous membrane

Fibularis tertius insertion

Dorsum of base of 5th metatarsal

Fibularis tertius action

Dorsiflexes ankle joint

aids in eversion of subtalar joint

Fibularis tertius innervation

Deep fibular nerve (L5, S1)

Fibularis longus origin

Head of fibula and proximal lateral fibula

Fibularis longus insertion

Base of the 1st metatarsal and medial cuneiform

Fibularis longus action

Evert subtalar joint

weakly plantarflex ankle joint

supports transverse arch of foot.

Fibularis longus innervation

Superficial fibular nerve (L5, S1, S2)

Fibularis brevis origin

Middle lateral fibula

Fibularis brevis insertion

Tuberosity of fifth metatarsal

Fibularis brevis action

Evert subtalar joint

weakly plantarflex ankle joint

Fibularis brevis innervation

Superficial fibular nerve (L5, S1, S2)

Gastrocnemius origin

Condyles of the femur, posterior surface

Gastrocnemius insertion

Calcaneus via calcaneal (Achilles) tendon

Gastrocnemius action

Flexes the knee

plantarflexes the ankle

Gastrocnemius innervation

Tibial nerve (S1, S2)

Soleus origin

Soleal line

proximal, posterior surface of tibia

posterior aspect of head of fibula

Soleus insertion

Calcaneus via calcaneal (Achilles) tendon

Soleus action

Plantarflexes the ankle

Soleus innervation

Tibial nerve (S1, S2)

Plantaris origin

Lateral supracondylar line of femur

Plantaris insertion

Calcaneus via calcaneal (Achilles) tendon

Plantaris action

Weakly assists the gastrocnemius

function is likely proprioceptive.

Plantaris innervation

Tibial nerve (S1, S2)

Popliteus origin

Lateral condyle of the femur and lateral meniscus

Popliteus insertion

Proximal, posterior aspect of tibia

Popliteus action

Weakly flexes knee joint

unlocks it by laterally rotating femur on fixed tibia OR medially rotating tibia of unplanted limb

Popliteus innervation

Tibial nerve (L4, L5, S1)

Flexor hallucis longus origin

Middle half of posterior fibula

Flexor hallucis longus insertion

Distal phalanx of digit 1

Flexor hallucis longus action

Flexes the first toe; weak plantarflexion of ankle; inverts the foot

Flexor hallucis longus innervation

Tibial nerve (S2, S3)

Flexor digitorum longus origin

Middle, posterior surface of tibia

Flexor digitorum longus insertion

Distal phalanges of digits 2-5

Flexor digitorum longus action

Flexes digits 2-5; weak plantarflexion of ankle; invert the foot

Flexor digitorum longus innervation

Tibial nerve (L4, L5)

Tibialis posterior origin

Proximal posterior shafts of tibia and fibula; and interosseous membrane

Tibialis posterior insertion

All five tarsal bones, and bases of 2nd-4th metatarsals

Tibialis posterior action

Plantarflexes ankle joint; inverts foot; maintains medial longitudinal arch of foot

Tibialis posterior innervation

Tibial nerve (L4, L5, S1)

Abductor hallucis

Origin: Medial process of calcaneus and plantar aponeurosis

Abductor hallucis

Insertion: Medial side of base of proximal phalanx of 1st digit

Abductor hallucis

Action: Abducts the first toe; assists to flex the first toe

Abductor hallucis

Innervation: Tibial nerve (L5, S1)

Flexor digitorum brevis

Origin: Medial process of calcaneus and plantar aponeurosis

Flexor digitorum brevis

Insertion: Middle phalanges of digits 2-5

Flexor digitorum brevis

Action: Flexes MTP and PIP joints of digits 2-5

Flexor digitorum brevis

Innervation: Tibial nerve (S1, S2, S3)

Abductor digiti minimi

Origin: Lateral process of calcaneus and plantar aponeurosis

Abductor digiti minimi

Insertion: Proximal phalanx of digit 5

Abductor digiti minimi

Action: Abducts and flexes digit 5

Abductor digiti minimi

Innervation: Tibial nerve (S1, S2, S3)

Quadratus plantae

Origin: Medial and lateral sides of plantar surface of calcaneus

Quadratus plantae

Insertion: Posterior, lateral aspect of flexor digitorum longus tendon

Quadratus plantae

Action: Assist flexor digitorum longus to flex digits 2-5

Quadratus plantae

Innervation: Tibial nerve (L5 - S3)

Lumbricals

Origin: Tendons of flexor digitorum longus

Lumbricals

Insertion: Medial aspect of extensor expansion over digits 2-5

Lumbricals

Action: Flexes MTP joint and extends PIP/DIP joints of digits 2-5

Lumbricals

Innervation: Tibial nerve (L5 - S3)

Flexor hallucis brevis

Origin: Plantar surfaces of cuboid and lateral cuneiform

Flexor hallucis brevis

Insertion: Both sides of base of proximal phalanx of 1st digit

Flexor hallucis brevis

Action: Flexes the 1st MTP joint of the great toe

Flexor hallucis brevis

Innervation: Tibial nerve (L5, S1)

Adductor hallucis

Origin: Oblique head: bases of second through fourth metatarsals; Transverse head: plantar ligament of 3rd-5th metatarsophalangeal joints

Adductor hallucis

Insertion: Lateral surface of base of proximal phalanx of 1st toe

Adductor hallucis

Action: Adducts 1st digit; assists in maintaining transverse arch of foot

Adductor hallucis

Innervation: Tibial nerve (S1 - S3)

Flexor digiti minimi brevis

Origin: Base of 5th metatarsal

Flexor digiti minimi brevis

Insertion: Base of proximal phalanx of 5th toe

Flexor digiti minimi brevis

Action: Flexes the MTP joint of the 5th digit

Flexor digiti minimi brevis

Innervation: Tibial nerve (S1 - S3)

Plantar interossei (3 muscles)

Origin: Medial surfaces of 3rd-5th metatarsals

Plantar interossei (3 muscles)

Insertion: Medial surfaces of proximal phalanges of 3rd-5th toes

Plantar interossei (3 muscles)

Action: Adduct and flex third through fifth MTP joints

Plantar interossei (3 muscles)

Innervation: Tibial nerve (S1 - S3)

Dorsal interossei (4 muscles)

Origin: Adjacent surfaces of metatarsals 1-5

Dorsal interossei (4 muscles)

Insertion: First: medial surface of proximal phalanx of 2nd toe; Second through fourth: lateral surfaces of proximal phalanges of 2nd-4th toes

Dorsal interossei (4 muscles)

Action: Abduct and flex second through fourth MTP joints

Dorsal interossei (4 muscles)

Innervation: Tibial nerve (S1 - S3)

Extensor hallucis brevis

Origin: Dorsal surface of calcaneus

Extensor hallucis brevis

Insertion: Proximal phalanx of 1st toe

Extensor hallucis brevis

Action: Extend the first toe

Extensor hallucis brevis

Innervation: Deep fibular nerve (L4 - S1)

Extensor digitorum brevis

Origin: Dorsal surface of calcaneus

Extensor digitorum brevis

Insertion: 2nd-4th toes via the extensor digitorum longus tendons

Extensor digitorum brevis

Action: Extend the second through fourth toes

Extensor digitorum brevis

Innervation: Deep fibular nerve (L4 - S1)