10. Foot and Toes Flashcards
Fibularis longus
Origin
Insertion
Action
Superficial lateral muscle; overlies fibula
O- head and upper portion of lateral side of fibula
I- by tendon that curves under foot to first metatarsal and medial cuneiform
A- plantar flexes and everts foot
Fibularis brevis
Origin
Insertion
Action
Smaller muscle; deep to fibularis longus, enclosed in a common sheath
O- distal fibula shaft
I- by tendon running behind lateral malleolus to insert on proximal end of fifth metatarsal
A- plantar flexes and everts foot
Extensor hallucinate longus
Origin
Insertion
Action
deep to extensor digitorum longus and tibilalis anterior; narrow origin
O- anteromedial fibula shaft and interosseous membrane
I- tendon inserts on distal phalanx of great toe
A- extends great toe; dorsiflexes foot
Tibialis anterior
Origin
Insertion
Action
Superficial muscle of anterior leg; laterally parallels sharp anterior margin of tibia
O- lateral condyle and upper two-thirds of tibial shaft; interosseous membrane
I- by tendon into interior surface of medial cuneiform and first metatarsal bone
A- prime mover of dorsiflexion; inverts foot; assists in supporting medial longitudinal arch of foot
Tibialis posterior
Origin
Insertion
Action
Thick, flat muscle deep to soleus, placed b/w posterior flexors
O- superior tibia and fibula and interosseous membrane
I- tendon passes behind medial malleolus and under arch of foot; inserts into several tarsals and metatarsals
A- prime mover of foot inversion; plantar flexes foot; stabilizes medial longitudinal arch of foot
Extensor digitorum longus
Origin
Insertion
Action
Unipennate muscle on anterolateral surface of leg; lateral to tibialis anterior muscle
O- lateral condyle of tibia; proximal three-fourths of fibula, interosseous membrane
I- middle and distal phalanges of toes - via extensor expansion
A- prime mover of toe extension (acts mainly at metatarsophalangeal joint); dorsiflexes foot
Flexor digitorum longus
Origin
Insertion
Action
Long, narrow muscle; runs medial to and partially overlies tibialis posterior
O- extensive origin on the posterior tibia
I- tendon runs behind medial malleolus and splits to insert into distal phalanges of toes
A- plantar flexes and inverts foot; flexes toes; helps foot “grip” ground
Flexor hallucis longus
Origin
Insertion
Action
Bipennate muscle; lies lateral to inferior aspect of tibialis posterior
O- middle part of shaft of fibula; interosseous membrane
I- tendon runs under foot to distal phalanx of great toe
A- plantar flexes and inverts foot; great toe at all joints. “push off” muscle during walking
