Anatomy of the foot

3. Two tiny, round sesamoid bones sit under the head of the first metatarsal (big toe) to help with smooth movement.
4. Bone The calcaneus, or heel bone, is the largest bone in the foot, providing a base for the hindfoot.
9. Toe Structure The big toe (hallux) has only two phalanges, while the other four toes have three each.
10. and Stability Joints are classified by motion, with hindfoot joints allowing gliding and forefoot joints (condyloid) allowing for flexion, extension, adduction, and abduction.
11. Count The foot features 33 joints, including the subtalar, talocalcaneonavicular, and tarsometatarsal joints.
13. Ligaments These ligaments connect the metatarsals to the tarsal bones, maintaining the integrity of the midfoot arch.
14. Fascia The largest ligament, the plantar fascia, extends from the heel to the forefoot, supporting the arch and absorbing shock.

1. Count Each foot consists of 26 bones, accounting for about one-quarter of the total bones in the human body.
2. Surfaces Articular cartilage and synovial fluid line the joints, reducing friction and acting as a shock absorber.
5. Support The long plantar ligament and calcaneocuboid ligament are crucial for maintaining the longitudinal arch of the foot.
6. Mechanism Over 100 ligaments in the foot connect bone to bone, providing stability and structural integrity to the 33 joints.
7. Grouping The bones are divided into three groups: 7 tarsals (hind/midfoot), 5 metatarsals (forefoot), and 14 phalanges (toes).
8. Function The subtalar joint (between the talus and calcaneus) is crucial for navigating uneven terrain, allowing the foot to tilt side-to-side.
10. Lateral Support Medial ligaments (inside) and lateral ligaments (outside) prevent excessive tilting and stabilize the foot against rotation.
12. Action The ankle includes a hinge joint that allows for flexion (bending) and extension (straightening) of the foot.