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| Muscle | Origin | Insertion | Action | Nerve |
| Dorsal Surface of Foot |
| extensor digitorum brevis | upper anterolateral calcaneus | middle & distal phalanges of toes #2-#4 (via EDL & extensor expansion) | extension of toes #2-#5 | deep peroneal (fibular) nerve (L5, S1) |
| extensor hallucis brevis | upper anterolateral calcaneus | distal phalanges of big toe (via EHL & extensor expansion) | extension of big toe at MTP; dorsiflexion & inversion of foot | deep peroneal (fibular) nerve (L5, S1) |
| Plantar Surface of Foot |
| Layer 1 |
| abductor hallucis | calcaneal tuberosity, flexor retinaculum & plantar aponeurosis | base of proximal phalanx of big toe (medial plantar side) | abduction of big toe (primary action) | medial plantar nerve (S1, S2) |
| abductor digiti minimi (foot) | calcaneal tuberosity, flexor retinaculum & plantar aponeurosis | base of proximal phalanx of little toe (lateral plantar side) | abduction of little toe (primary action) | lateral plantar nerve (S1, S2) |
| abductor ossis metatarsi quinti | fibers of the abductor digiti minimi muscle | 5th metatarsal (tuberosity) | abducts 5th ray | lateral plantar nerve (S1, S2) |
| flexor digitorum brevis | calcaneal tuberosity & plantar aponeurosis | base of middle phalanges of toes #2-#5 (tendon splits near insertion) | flexion of toes #2-#5 | medial plantar nerve (S1, S2) |
| Layer 2 |
| quadratus plantae | medial & lateral calcaneus | flexor digitorum longus tendon (lateral margin) | flexion of distal phalanxes (2nd-5th toes) | lateral plantar nerve (S1, S2) |
| lumbricals (foot) | Flexor digitorum longus (1st: medial aspect of tendon to 2nd toe; 2nd-4th: two heads between tendons in which they lie) | tendon of extensor digitorum longus & extensor expansion (on the dorsal medial side) | extension of toes 2-5 (at PIP & DIP joints); flexion of toes 2-5 (at MTP joints) | 1st lumbrical: medial plantar nerve (S1, S2, S3); 2nd-4th lumbricals: lateral plantar nerve (S1, S2, S3) |
| Layer 3 |
| flexor digiti minimi (foot) | base of 5th metatarsal & distal of peroneus longus | base of proximal phalanx of little toe (5th toe) | flexion of little toe (at MTP joint) | lateral plantar nerve (S2, S3) |
| flexor hallucis brevis | cuboid (medial side) & lateral cuneiform | base of proximal phalanx of big toe (medial & lateral sides) | flexion of big toe (at MTP joint) | medial plantar nerve (S1, S2) |
| adductor hallucis | oblique head: base of 2nd-4th metatarsals & distal tendon of peroneus longus; transverse head: deep transverse metatarsal ligament & plantar ligaments at MTP joints | base of proximal phalanx of big toe (lateral aspect) | adduction of big toe (at MTP joint); flexion of hallux (at MTP joint) | lateral plantar nerve (S2, S3) |
| Layer 4 |
| dorsal interossei (foot) | from both metatarsals between which they lie | base of proximal phalanx closest to axis of foot (2nd ray) | abduction of toes 2-4 (at MTP); flexion toes 2-4 (at MTP) | lateral plantar nerve (S2, S3) |
| plantar interossei | medial aspect of 3rd-5th metatarsals (each muscle has a single head) | medial aspect of base of proximal phalanx of same ray (of 3rd-5th rays) | adduction of toes 3-5 (at PIP & DIP joints); flexion of toes 3-5 (at MTP joints), extension of toes 3-5 (at PIP & DIP joints) | lateral plantar nerve (S2, S3 |
Vertebral Column