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Muscles Acting On The Foot and Ankle |
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Origin |
Insertion |
Innervation |
Action |
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POSTERIOR & SUPERFICIAL: |
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Gastrocnemius |
Medial head: posterior surface of distal femur just above medial condyle |
Via calcaneal (Achilles) tendon to posterior surface of calcaneus |
Tibial nerve (S1 – S2) |
Plantar flexes foot and flexes knee |
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Lateral head: upper posterolateral surface of lateral femoral condyle |
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Soleus |
Soleal line & medial border of tibia; posterior surface of fibular head |
Via calcaneal (Achilles) tendon to posterior surface of calcaneus |
Tibial nerve (S1 – S2) |
Plantar flexes the foot |
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Plantaris |
Inferior part of lateral supracondylar line of femur & oblique popliteal ligament of knee |
Via calcaneal (Achilles) tendon to posterior surface of calcaneus |
Tibial nerve (S1 – S2) |
Plantar flexes foot and flexes knee |
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POSTERIOR & DEEP: |
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Popliteus |
Posterior surface of proximal tibia |
Lateral femoral condyle |
Tibial nerve (L4 – S1) |
Unlocks the knee joint by laterally rotating the femur on a fixed tibia (“screw mechanism” |
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Flexor hallucis longus |
Posterior surface of fibula and adjacent interosseous membrane |
Plantar surface of distal phalanx of hallux (big toe) |
Tibial nerve (S2 – S3) |
Flexes hallux |
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Flexor digitorum longus |
Medial side of posterior surface of the tibia |
Plantar surfaces of bases of distal phalanges of the lateral four toes |
Tibial nerve (S2 – S3) |
Flexes lateral four toes |
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Tibialis posterior |
Posterior surfaces of interosseous membrane & adjacent regions of tibia and fibula |
Tuberosity of navicular & adjacent region of medial cuneiform |
Tibial nerve (L4 – L5) |
Inversion & plantar flexion of foot; support of medial arch of foot during walking |
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LATERAL: |
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Peroneus (fibularis) longus |
Upper lateral surface of fibula, head of fibula & lateral tibial condyle |
Undersurface of lateral sides of distal end of medial cuneiform & base of 1st metatarsal |
Superficial fibular/peroneal nerve (L5 – S2) |
Eversion & plantarflexion of foot; supports arches of foot |
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Peroneus (fibularis) brevis |
Lower two-thirds of lateral surface of shaft of fibula |
Lateral tubercle at base of 5th metatarsal |
Superficial fibular/peroneal nerve (L5 – S2) |
Eversion of foot |
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ANTERIOR: |
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Medial & inferior surfaces of medial cuneiform & adjacent surfaces on base of 1st metatarsal |
Deep fibular/peroneal nerve (L4 – L5) |
Dorsiflexion of foot at ankle joint; inversion of foot; dynamic support of medial arch of foot |
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Extensor hallucis longus |
Middle half of medial surface of fibula & adjacent surface of interosseus membrane |
Dorsal surface of base of distal phalanx of hallux |
Deep fibular/peroneal nerve (L5 – S1) |
Extension of hallux & dorsiflexion of foot |
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Extersor digitorum longus |
Proximal half of medial surface of fibula & related surface of lateral tibial condyle |
Via dorsal digital expansions into bases of distal & middle phalanges of lateral four toes |
Deep fibular/peroneal nerve (L5 – S1) |
Extension of lateral four toes and dorsiflexion of foot |
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Peroneus (fibularis) tertius |
Distal part of medial surface of fibula |
Dorsomedial surface of base of 5th metatarsal |
Deep fibular/peroneal nerve (L5 – S1) |
Dorsiflexion and eversion of foot |
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INTRINSIC MUSCLES OF THE FOOT: |
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Extensor digitorum brevis |
Superolateral surface of the calcaneus |
Base of proximal phalanx of hallux & lateral sides of the tendons of extensor digitorum longus of 2nd to 4th toes |
Deep fibular/peroneal nerve (S1 – S2) |
Extension of metatarsophalangeal joint of hallux; flexion of 2nd to 4th toes |
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Dorsal interossei |
Sides of adjacent metatarsals |
Dorsal expansions & bases of proximal phalanges of 2nd to 4th toes |
Lateral plantar nerve from tibial nerve. First & second dorsal interossei also innervated by deep fibular/peroneal nerve (S2 – S3) |
Abduction of 2nd to 4th toes at metatarsophalangeal joints; resist extension of metatarsophalangeal joints & flexion of interphalangeal joints |
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Plantar interossei |
Medial sides of metatarsals of 3rd to 5th toes |
Dorsal expansions & bases of proximal phalanges of toes 3 to 5 |
Lateral plantar nerve from tibial nerve (S2 – S3) |
Adduction of 3rd to 5th toes at metatarsophalangeal joints; resist extension of metatarsophalangeal joints & flexion of interphalangeal joints |
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Flexor digiti minimi brevis |
Base of 5th metatarsal & related sheath of fibularis (peroneus) longus tendon |
Lateral side of base of proximal phalanx of little toe |
Lateral plantar nerve from tibial nerve (S2 – S3) |
Flexes little toe at metatarsophalangeal joint |
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Flexor hallucis brevis |
Plantar surface of cuboid & lateral cuneiform; tendon of tibialis posterior |
Lateral & medial sides of base of proximal phalanx of the hallux |
Medial plantar nerve from tibial nerve (S1 – S2) |
Flexes metatarsophalangeal joint of the hallux |
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Flexor digitorum brevis |
Medial process of calcaneal tuberosity & plantar aponeurosis |
Sides of plantar surface of middle phalanges of lateral four toes |
Medial plantar nerve from the tibial nerve (S2 – S3) |
Flexes lateral four toes at proximal interphalangeal joint |
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Quadratus planae |
Medial surface of calcaneus & lateral process of calcaneal tuberosity |
Lateral side of tendon of flexor digitorum longus in proximal sole of foot |
Lateral plantar nerve from tibial nerve (S1 – S3) |
Assists flexor digitorum longus in flexing 2nd to 5th toes |
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Abductor digiti minimi |
Lateral & medial processes of calcaneal tuberosity, & band of connective tissue connecting calcaneus with base of 5th metatarsal |
Lateral side of base of proximal phalanx of little toe |
Lateral plantar nerve from tibial nerve (S2 – S3) |
Abducts little toe at the metatarsophalangeal joint |
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Abductor hallucis |
Medial process of calcaneal tuberosity |
Medial side of base of proximal phalanx of hallux |
Medial plantar nerve from the tibial nerve (S2 – S3) |
Abducts & flexes hallux at metatarsophalangeal joint |
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Lumbricals |
First lumbrical – medial side of tendon of flexor digitorum longus associated with toe 2. |
Medial free margins of extensor hoods of toes 2 to 5 |
First lumbrical – medial plantar nerve from the tibial nerve. |
Flexion of metatarsophalangeal joint & extension of interphalangeal joints |
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Second, third &fourth lumbricals – adjacent surfaces of adjacent tendons of flexor digitorum longus |
Second, third & fourth lumbricals – lateral plantar nerve from tibial nerve (S2 – S3) |
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Adductor hallucis |
Transverse head – ligaments associated with metatarsophalangeal joints of lateral 3 toes. |
Lateral side of base of proximal phalanx of hallux |
Lateral plantar nerve from tibial nerve (S2 – S3) |
Adducts hallux at metatarsophalangeal joint |
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Oblique head – bases of 2nd to 4th metatarsals & from sheath covering fibularis (peroneus) longus |
