Anatomy of the Sole of Foot

Muscles of the plantar foot are divided into four layers:

First layer: 3 muscles
1-Flexor digitorum brevis muscle
2-Abductor hallucis muscle
3-Abductor digit minimi muscle

Second layer: 5 muscles/2 tendons
1-Flexor digitorum longus tendon
2-Flexor hallucis longus tendon
3-Quadratus plantae muscle
4-Lumbrical muscle

Third layer: 3 muscles
1-Flexor hallucis brevis muscle
2-Adductor hallucis muscle
3-Flexor digit minimi muscle.

Fourth layer: 7 muscles/ 2 tendons
1-Tibilais posterior tendon
2-Peroneus longus tendon
3-7 interoosues muscles.