Author: Dr Peter de Souza
Last modified: 20 November 2023

The quadratus plantae is one of the intrinsic muscles within the second layer of the plantar muscles of the foot.

The intrinsic muscles of the foot consist of one intrinsic muscle on the dorsal aspect of the foot (the extensor digitorum brevis), and 4 layers of muscles on the plantar aspect of the foot:

  • 1st layer: abductor hallucis, flexor digitorum brevis, abductor digiti minimi
  • 2nd layer: quadratus plantae, lumbricals
  • 3rd layer: flexor hallucis brevis, adductor hallucis, flexor digiti minimi brevis
  • 4th layer: dorsal interosseri, plantar interossei

Origin

  • Medial head: medial surface of calcaneus
  • Lateral head: lateral process of calcaneal tuberosity

Insertion

  •  Lateral side of tendon of flexor digitorum longus

Action

  • Assists flexor digitorum longus tendon in flexing toes 2-5

Innervation

  • Lateral plantar nerve from tibial nerve [S1 to S3]

Blood Supply

  •  Lateral plantar artery