Understanding Ankle Joint: Know About the Supporting Ligaments, Tendons, Muscles

Ankle Joint is hinged synovial joint supported by several ligament, tendon, cartilage and muscle. Ankle joint is made up of two joints, which functions together to achieve flexion (upward), extension (downward) and lateral (side to side) movement of the feet.

Ankle Joint–

• True Ankle Joint.
• Subtalar Joint.

The true ankle joint is composed of tibia, fibula and talus bone. Tibia lies on medial (inner) side and fibula lies on lateral (outer) side above the upper surface of talus. Ankle joint allows limited flexion and extension of the feet.

Subtalar joint is between talus and calcaneus bone. Talus sits on top of calcaneus bone. The subtalar joint allows side to side movements of the foot.

Ligaments are thick and tough band of fibrous tissue. The major ligaments of the ankle joints are as follows-

This is divided in following sub-groups

• Anterior tibio-fibular ligament- connects the tibia to fibula.
• Anterior tibio-talar ligament.
• Anterior talo-fibular ligament.

This is divided in following sub-groups

• Posterior tibio-talar ligament.
• Posterior fibula-talar ligament.

• Calcaneo-fibular ligament, attach the fibula to the calcaneus bone.

These lie on medial or inner side of the joint and connects tibia to the talus. Deltoid ligaments are divided in following subgroups-

• Tibionavicular.
• Tibiocalcaneal.
• Tibiotalar anterior.
• Tibiotalar posterior.

Capsular ligaments are thin and mostly support the anterior section of the joint.

• Anterior (front) capsular ligament
• Posterior (back of the joint) capsular ligaments

Tendons are like ligaments a tough band of fibrous tissue connects end of muscles to bones. Tendon facilitates anchoring of the muscles to the bone around the joint. Tendon helps to stabilize the joint.

List of tendons supporting ankle joint are as follows-

• Achilles Tendon– attaches calf muscles to back of calcaneus bone.
• Flexor Hallucis Longus– lies along the inside of the ankle and attaches to the big toe.
• Flexor Digitorum Longus– lies on medial or inside of the ankle joint and attaches to remaining 4 toes but big toe.
• Peroneus Tendon– divided as peroneus brevis and peroneus longus lies on outside of the ankle joint and attaches to shaft of 5th metatarsal bone and spreads to bottom of the foot.
• Posterior Tibial Tendon– attaches the midfoot and function is to maintain normal arch of the foot.
• Anterior Tibialis Tendon– attaches anterior tibialis muscles to the bones of the midfoot.

Muscles are not directly in contact with ankle joint. Tendons are distal end of muscles and lies in contact with the ankle joint.

The medial malleolus is the most prominent part of the lower end of the tibia, lies just under the skin on inner side of ankle joint.

Lateral malleolus is the bony prominence on outside of the ankle joint. Lateral malleolus is the lower end of the fibula bone and prone for fracture.