Anatomy of the Plantar Foot

A group of muscles on the palmar side of the foot responsible for flexing the metatarsophalangeal (MPJ) joint and extending the interphalangeal (IPJ) joints of the toes 3-5.

A group of muscles on the plantar side of the foot responsible for flexing the metatarsophalangeal (MPJ) joint and extending the interphalangeal (IPJ) joints of the toes 2-4.

A thick band of tissue that connects the sustentaculum tali (on the calcaneus) to the navicular bone in the foot.

A ligament that runs along the plantar surface of the foot, connecting the calcaneus to the cuboid bone.

A ligament that runs along the plantar surface of the foot, connecting the calcaneus to the cuboid and the metatarsal bases.

A curved structure formed by the bones of the foot, which helps to distribute weight, absorb shock and protect vital structures.

The highest point of a structure, especially an arch or curve.

A structural element that links the ends of an arch, preventing separation.

A structural element that links individual components of an arch, preventing separation.

A structural element that holds the apex of an arch from above.

A muscle located on the sole of the foot, originating from the medial calcaneal tubercle and plantar aponeurosis, with tendons inserting onto the proximal phalanx of each of the four lesser toes. It assists in flexing both the metatarsophalangeal (MTP) and proximal interphalangeal (PIP) joints of the toes.

Located on the medial side of the little toe, this muscle originates from the medial and lateral calcaneal tubercles and plantar aponeurosis, inserting into the lateral base of the proximal phalanx of the 5th toe. It helps flex and abduct the 5th toe's MTP joint.

This muscle is located in the middle layer of muscles in the foot, originating from the flexor digitorum longus (FDL) tendons and inserting into the base of the proximal phalanx and extensor hood of the lateral four toes. It assists in flexing the metatarsophalangeal (MP) joint and extending the interphalangeal (IP) joints, stabilizing the toes.

A muscle situated on the sole of the foot, originating from the body of the calcaneus and inserting into the lateral border of the FDL tendon. It helps to flex both the metatarsophalangeal (MP) and interphalangeal (IP) joints, ensuring a straight pull of the FDL tendon.

A deep muscle located in the sole of the foot, originating from the plantar aspect of the midfoot and inserting into the base of the 1st proximal phalanx, via the medial and lateral sesamoid bones. Primarily responsible for flexing the 1st metatarsophalangeal (MTP) joint.

Situated on the lateral side of the little toe, this muscle originates from the base of the 5th metatarsal and inserts into the lateral base of the 5th proximal phalanx. It helps to flex the 5th toe's metatarsophalangeal (MTP) joint.

A muscle located on the sole of the foot, consisting of two heads, the oblique and transverse. The oblique head originates from bases of the 2nd to 4th metatarsals and inserts into the base of the 1st proximal phalanx via the lateral sesamoid. The transverse head originates from the plantar plates of the 3rd to 5th metatarsals and also inserts into the base of the 1st proximal phalanx. It helps flex and adduct the 1st metatarsophalangeal (MTP) joint.

The thick, tough layer of connective tissue on the bottom of the foot, continuous with the deep fascia. It's anchored to the heel bone and extends to the toes, forming compartments for muscles.

Specializations of the superficial fascia on the sole of the foot, containing loose adipose tissue and fibrous septa. They provide cushioning and prevent fat from dispersing under weight-bearing.

A group of muscles on the sole of the foot that are organized according to their location and depth. The layers provide a functional framework for movement and stability.

The first layer of muscles on the sole. It includes Abductor hallucis, which helps to move the big toe away from the rest of the toes and flexes the big toe joint.

The main function of the plantar aponeurosis is to provide support to the plantar tissues and to anchor the skin to the skeleton. It also plays a role in forming compartments for the loculated fat pads and providing paths for nerves and blood vessels.

The sole of the foot differs from the dorsum (top) in several ways. The skin on the sole is thicker, hairless, and has many nerve endings and sweat glands. This makes it harder to identify deeper structures compared to the more superficial structures of the dorsum.

The nerves and blood vessels supplying the sole of the foot are located between the first and second layers of muscles. The medial and lateral plantar nerves and arteries, branching from the tibial nerve and artery, respectively, provide sensory and motor innervation and blood supply to the foot.

The superficial structures of the sole of the foot include loculated fat pads, the plantar aponeurosis, and the superficial layers of muscles.

The sole of the foot is organized into compartments (medial, central, lateral, and deep) based on the location of the muscles. The muscles are also arranged in four layers, from superficial to deep, with the most superficial muscles originating more proximally and inserting distally to the joint they act upon.

The Abductor hallucis muscle is located in the first layer of the sole. Its origin is the medial tubercle of the calcaneus and it inserts onto the plantar aponeurosis, the flexor digitorum brevis (FDB) muscle, and the base of the proximal phalanx of the big toe. The Abductor hallucis is responsible for abducting (moving away from the middle) and flexing the first metatarsophalangeal joint (the joint between the big toe and the foot).