Joints of the Ankle and Foot
Your feet and ankles need to be sturdy, but they also need to be agile enough to adapt to slipping off a curb or doing some fancy footwork on the tennis court. Good thing they have as many joints as they do.
The ankle joint
The ankle joint is a synovial hinge joint, so you can plantarflex and dorsiflex. It allows a little wiggle from side to side, but most of the rest of the movement comes from the foot joints. The ankle joint is made up of distal ends of the tibia and fibula, which form a socket that fits over the top portion of the talus. The bones are held together by several ligaments.
Medial (deltoid) ligament of the ankle: This strong ligament attaches to the medial malleolus. It has four parts named for the bones that they attach to: the tibionavicular, the tibiocalcaneal, the anterior tibiotalar, and the posterior tibiotalar.
Lateral ligament of the ankle: This ligament is made up of three bands that start at the lateral malleolus. These ligaments are named for the bones they attach to:
Anterior talofibular ligament: This ligament runs to the lateral surface of the talus.
Calcaneofibular ligament: This ligament runs to the lateral surface of the calcaneus.
Posterior talofibular ligament: This ligament runs to the lateral tubercle (small rounded eminence) of the talus.
If you’ve ever sprained an ankle, you injured one or more of the ligaments that hold the joint together. The lateral ligaments are damaged more often than the stronger medial ligament.
The foot and toe joints
The foot contains a number of joints, but two important joints are the subtalar and transverse tarsal joints. These two joints allow you to invert and evert the foot.
Subtalar joint: This joint is the posterior joint formed between the talus and the calcaneus. It’s a synovial joint, and it’s stabilized by medial, lateral, and interosseous talocalcaneal ligaments.
Transverse tarsal joint: The transverse tarsal joint is actually a combination of the following two joints:
Talocalcaneonavicular joint: This synovial joint is formed between the talus and the calcaneus and the navicular bones. It’s stabilized by the plantar calcaneonavicular ligament.
Calcaneocuboid joint: Another synovial joint, this one is formed between the front of the calcaneus and the posterior surface of the cuboid bone. It’s stabilized by the bifurcated ligament on the top, the long plantar ligament on the bottom, and the short plantar ligament, which is deep to (located underneath) the long plantar ligament.
The remaining joints of the foot allow for a little movement of the foot and toes:
Cuneonavicular joint: This synovial joint is formed between the navicular bone and the three cuneiform bones. It is supported by dorsal and plantar cuneonavicular ligaments. It allows for some gliding movement.
Cuboideonavicular joint: This fibrous joint is between the cuboid and navicular bones. It’s supported by dorsal, plantar, and interosseous ligaments.
Tarsometatarsal joints: These synovial joints are formed between the tarsal bones and the bases of the metatarsal bones. These joints are strengthened by dorsal, plantar, and interosseus ligaments.
Intermetatarsal joints: These synovial joints involve the bases of the metatarsal bones. All these joints are strengthened by dorsal, plantar, and interosseus ligaments.
Metatarsophalangeal joints: These synovial joints are between the heads of the metatarsal bones and the bases of the proximal phalanges. They’re supported by plantar and collateral ligaments. They allow you to flex and extend your toes as well as move them apart and closer together.
Interphalangeal joints: These joints connect the phalanges. They’re synovial joints strengthened by collateral and plantar ligaments, and they let you flex and extend your toes.