Foot
Foot (pes) is the distal section of the lower limb, which bears the entire body weight and ensures movement. It consists of 26 bones, 33 joints and more than 100 ligaments. Both feet contain a quarter of all the bones of the skeleton.
Skeleton of the foot
Tars (7 bones):
- The talus is the only bone of the foot that does not have muscle attachments. Articulates with the lower leg (ankle joint)
- Heel bone - the largest bone of the foot, takes the main load when walking
- Scaphoid, cuboid, three wedge-shaped
Metarsus - 5 tubular bones. The first metatarsal is the thickest and carries the greatest load during repulsion.
Phalanges - 14 bones (3 in each finger, except I - 2 phalanges).
Arches
The foot is not a flat support, but an arched structure with three arches:
- Medial longitudinal arch - the highest, from the heel through the talus and navicular bones to the I–III metatarsals. Main shock absorber
- Lateral longitudinal arch - lower, from the heel through the cuboid to the IV-V metatarsals. Support vault
- Transverse arch - at the level of the sphenoid and cuboid bones
Vaults supported:
- Plantar aponeurosis - a powerful fibrous plate from the heel to the toes
- Spring ligament (plantar calcaneonavicular) - supports the head of the talus
- Long plantar ligament - the longest ligament of the foot
- Muscles of the foot and lower leg
Ankle joint
The ankle joint is a trochlear joint, formed by the tibia, fibula and talus bones. The “fork” of the tibia covers the block of the talus. Movement: dorsiflexion (20°) and plantar flexion (45°).
Biomechanics of walking
The step cycle includes:
- Heel Contact - Heel bone takes up 60% of body weight
- Roll - the load is transferred along the lateral arch
- Push-off - big toe and metatarsal heads
When walking, the foot alternately becomes rigid (for pushing off) and flexible (for adapting to unevenness). This mechanism is called the windlass effect: when the big toe is extended, the plantar aponeurosis is stretched, which “tightens” the arch.
Flat feet
Flat feet - decreased arches of the feet. The medial arch flattens and the foot rolls inward (pronation). This affects the entire kinetic chain - knees, hips and spine.
The anatomy of the foot is important for podiatrists, podiatrists and sports physicians when selecting orthopedic insoles and planning surgical interventions.
Do you want to see the arches of your feet and ankle joint in volume? Interactive models are available in 3D atlas Humio - rotate, zoom and study the biomechanics of the step.