Muscle Chart: 2nd Plantar Layer

Question 1

Quadratus Plantae

Origin, Insertion, Innervation, Blood Supply

Answer 1

Origin: Medial and lateral side of the plantar surface of the calcaneus

Insertion: Posterior, lateral aspect of the flexor digitorum longus tendon

Innervation: Lateral plantar nerve from tibial nerve (S1, S2)

Blood Supply: Lateral plantar artery

Question 2

Quadratus Plantae Movements

Answer 2

Assist flexor digitorum longus to flex 2nd-5th toes

Question 3

Lumbricals

Origin, Insertion, Innervation, Blood Supply

Answer 3

Origin: Tendons of the flexor digitorum longus

Insertion: Bases of the proximal phalanges of 2nd and 5th toes with extensor digitorum longus tendons (on dorsal surface of the toes)

Innervation: 1st lumbrical (medial side) from medial plantar nerve (tibial) (L4, L5, S1)

2nd-4th lateral plantar nerve (tibial) (L4, L5, S1, S2)

Blood Supply: Medial plantar artery

Question 4

Lumbricals Movements

Answer 4

Flex the proximal phalanges of 2-5 toes at MTP joint

Extend middle and distal phalanges of 2-5 toes at interphalangal joints (PIP and DIP)