There are 30 bones in each leg and foot; 26 are in the foot and ankle. Tendons and ligaments attach to bone and muscle to help them coordinate movement. The leg has only four bones but they're much bigger and heavier than those found in the ankle and foot. Lower extremity bones get progressively smaller and more numerous as you move down the leg. The bone at the top of the leg is the largest and heaviest; the lower leg bones are thinner and smaller. The ankles and feet have many small bones.
Upper Leg
The upper leg has only one bone, the femur, the largest and heaviest bone in the human body. The rounded projection at the upper end of the femur fits into the hip socket, medically called the coxal bone. The neck of the femur, located between the head and body of the femur, is a common fracture site in people with osteoporosis.
Lower Leg
Two bones make up the lower leg, the tibia and fibula. The kneecap, or patella, found between the upper and lower leg, is a sesamoid bone, which means it's embedded in a tendon. The tibia, sometimes called the shinbone, is the larger of the lower leg bones and the second largest bone in the body. The much thinner fibula is located on the outer part of the leg.
Ankle
Although people refer to the ankle as if it were a single bone, it is made up of seven bones. The talus lies next to the tibia and fibula. The calcaneous, or heel bone, located at the back of the foot, is the strongest and largest of the tarsal, or ankle bones. Three cuneiform bones, the cuboid bone and the navicular bone round out the ankle. Some people have an extra navicular bone called an accessory navicular. An accessory navicular bone is common and can cause problems with the posterior tibial tendon that attaches to it, eOrthopod states.
Foot
The foot contains the metatarsals, five bones that run the length of the foot, and the phalanges, the bones of the toes. The big toe, also called the hallux, has two bones; the other four toes each have three. Underneath the first metatarsal embedded in the tendon are small round bones known as sesamoid bones; these usually aren't counted in the total number of foot bones. Some people have extra bones in their feet, called ossicles.
