Quadratus Plantae Muscle
The muscle highlighted is the
quadratus plantae muscle of the foot. The intrinsic muscles on the plantar aspect of the foot are divided into
four layers. The quadratus plantae muscle is found in the
second layer of muscles. There are
two muscles in the second layer:
- Quadratus plantae
- Lumbricals
The muscles in the second layer are associated with the tendons of the
flexor digitorum longus muscle. This tendon forms the site of insertion for the quadratus plantae muscle, and forms the site of origin for the four lumbricals. The quadratus plantae muscle has two heads – a
medial head and a
lateral head.
Origin: Medial surface of calcaneus and lateral process of calcaneal tuberosity
Insertion: Lateral aspect of flexor digitorum longus tendon.
Innervation: Lateral plantar nerve
Action: Flexion of toes 2-5 (assists the action of flexor digitorum longus) Learn more about the anatomy of the muscles of the foot in
this tutorial.