Arches of the Foot

Anatomical structure and function of the foot arches

Arches of the Foot are structural features formed by the tarsal bones, metatarsal bones, and supported by ligaments, tendons, and intrinsic muscles of the foot. They provide strength and flexibility, allowing the foot to support the weight of the human body during standing, walking, and running.

The bony architecture of the foot is arranged into multiple arches to maximize support with minimal material. These arches distribute body weight and provide shock absorption. There are two main types:

• Longitudinal arches – running lengthwise
• Transverse arches – running across the foot

Longitudinal Arches

The longitudinal arches are the most prominent and are divided into:

Medial Longitudinal Arch

Photograph showing the medial arch of the foot

The medial longitudinal arch is the higher and more elastic of the two. It is composed of the following bones:

• Calcaneus
• Talus
• Navicular bone
• Three cuneiform bones
• First, second, and third metatarsals

The highest point is the superior articular surface of the talus. The posterior end rests on the tuberosity of the calcaneus, while the anterior end is supported by the heads of the first three metatarsals.

The stability and elasticity of this arch are maintained by:

• Plantar calcaneonavicular ligament (spring ligament)
• Deltoid ligament
• Tibialis posterior muscle
• Tibialis anterior muscle
• Peroneus longus muscle
• Plantar aponeurosis
• Intrinsic muscles of the foot

The joint most susceptible to collapse is the talonavicular joint, which is reinforced by the spring ligament and the fan-like insertion of the tibialis posterior tendon.

Lateral Longitudinal Arch

The lateral longitudinal arch is flatter and more rigid. It comprises:

• Calcaneus
• Cuboid bone
• Fourth and fifth metatarsals

The apex lies at the calcaneocuboid joint, known for its locking mechanism, allowing limited motion. This arch is stabilized by:

• Long plantar ligament
• Plantar calcaneocuboid ligament (short plantar)
• Extensor digitorum longus muscle
• Flexor digitorum brevis muscle
• Abductor digiti minimi muscle

While the medial and lateral arches are often discussed separately, functionally they contribute to the unified longitudinal arch of the foot. Notably, a core segment of the longitudinal arch includes the cuboid, third cuneiform, and third metatarsal.

Transverse Arches

The foot also exhibits a series of transverse arches, particularly at:

• The base of the metatarsal bones
• The cuboid and cuneiform bones region

These arches form semi-domes with their concavities directed inferiorly and medially. When both feet are placed together, they form a complete dome.

Stabilization of the transverse arches involves:

• Interosseous ligaments
• Plantar ligaments
• Dorsal ligaments
• Adductor hallucis muscle (transverse head)
• Peroneus longus muscle (crosses the foot and supports the arch)

Function

The arches of the foot are essential in:

• Supporting body weight in various postures
• Absorbing impact during locomotion
• Distributing pressure evenly
• Assisting in propulsion during gait

The medial arch specifically accommodates soft tissue structures such as the plantar aponeurosis, which acts as a spring to absorb and release energy, making gait more efficient and protecting the musculoskeletal system from overuse injuries.

Clinical Significance

• Flattening of the arches results in pes planus (flat feet), which may cause pain or impaired gait.
• Exaggeration results in pes cavus, leading to instability or increased risk of injury.
• The arches are tested during physical examination and gait analysis and may be supported with orthotic devices.

Additional Images

• 

  Skeleton of foot - medial aspect

• 

  Skeleton of foot - lateral aspect

• 

  Photograph showing arch structure

Bibliography

• R. Fick: Handbuch der Anatomie und Mechanik der Gelenke (Bardeleben’s Handbuch der Anatomie)

External Links

• Overview at gla.ac.uk
• Arches of the Foot – Archive
• Arches diagram

Gray's Anatomy

• Gray's Anatomy Contents
• Gray's Anatomy Subject Index
• About Classic Gray's Anatomy
• Glossary of anatomy terms

Anatomy atlases (external)

[1] - Anatomy Atlases

Adapted from the Classic Grays Anatomy of the Human Body 1918 edition (public domain)