Arches of the foot

Bones

The bones participating in the formation of the arch are the following:

• the medial three metatarsals up to their heads
• the sesamoid bones
• the three cuneiforms
• the navicular
• talus
• calcaneus 

The arch consists of two pillars. The anterior pillar consists of the medial three metatarsal heads whilst the tuberosity of the calcaneus forms the posterior pillar.

Ligaments

The supporting ligaments provide more stability than the bones of the arch. One of these ligamentous structures, the plantar aponeurosis, acts as a supporting beam between the two pillars. Another important structure, the spring ligament, supports the head of the talus. The talocalcaneal ligament and the anterior fibres of the deltoid ligament also provide stability for this arch.

Muscles

Muscles in the foot also help support the medial longitudinal arch. These include:

• flexor hallucis longus
• flexor digitorum longus
• abductor hallucis
• flexor digitorum brevis muscles
• tibialis posterior, which is the most important muscle in the maintenance of the arch as damage to its tendon results in collapse of the arch.

The tibialis posterior and anterior muscles help to raise the medial border of the arch whilst the flexor hallucis longus acts as a bowstring. 

Bones

The less prominent lateral longitudinal arch is formed by the following:

• calcaneus 
• the cuboid
• the fourth and fifth metatarsals

Like its medial counterpart, the lateral arch consists of two pillars, which help support the arch. The anterior pillar consists of the fourth and fifth metatarsal heads whilst the calcaneus forms the posterior pillar. The main contributor to stabilisation of the arch is the fibularis longus tendon.

Soft tissues

Ligaments also have an important role in the stabilisation of this arch and include the plantar aponeurosis and the long and short plantar ligaments, which act as bowstrings beneath the arch. Other muscles and tendons, apart from the fibularis longus tendon, which contribute to the maintenance of this arch, include:

• lateral two tendons of flexor digitorum longus assisted by flexor accessorius
• abductor digiti minimi
• lateral half of flexor digitorum brevis
• fibularis brevis
• fibularis tertius

Bones

The transverse arch runs in a coronal plane and consists of the following:

• the five metatarsal bases
• the cuboid
• the cuneiform bones 

The intermediate and lateral cuneiforms are wedge shaped which aids in maintenance of the arch. The medial and lateral longitudinal arches act as pillars for the transverse arch.

Soft tissues

The most important ligaments of this arch are the ligaments between the cuneiforms and bases of the five metatarsal bones. Clinically, those extending from the first cuneiform bone to the base of the second metatarsal bone named Lisfranc ligaments (dorsal, interosseous, and plantar) are of particular importance.

The curvature of the arch is mainly maintained by the fibularis longus tendon, assisted by the tibialis posterior tendon, which both cross under the sole of the foot. The deep transverse ligaments, the transverse head of adductor longus and the fibularis longus tendon, also help to stabilize this arch.

More details about the bones and arches of the foot are provided below:

Weight bearing

The arches of the foot have an important role in weight bearing. During standing, the weight of the body is distributed throughout the bones in the foot by the arches. The weight is transmitted from the tibia to the talus, before being transmitted posteriorly to the calcaneus. It is also transmitted anteriorly to the navicular, cuneiforms and metatarsals. The lateral longitudinal arch is mostly involved in transmitting this weight and makes more contact with the ground than the medial one.

Do you think you know all the bones forming the foot arches? Test your knowledge, learn efficiently and retain the information better using Kenhub's skeletal system quizzes!

Movement

The medial longitudinal arch also has an important role in shock absorption and propulsion during walking, running and jumping. The arch acts like a springboard, as its anterior pillar is the point of take-off during these activities. The process of walking is referred to as the gait cycle and this consists of two phases: a stance phase and a swing phase. During the stance phase, the forefoot pronates which flattens the medial longitudinal arch and the transverse arch. During the swing phase, the hind foot supinates which causes the medial longitudinal arch to elevate. This high arch acts as a rigid lever for propulsion.