Ankle joint- ligaments

Medial collateral ligament (deltoid ligament) attaches to the medial malleolus of the tibia and the navicular, talus, and calcaneus bones. This ligament prevents medial distraction (eversion) and excessive range of motion. It is subdivided into four parts:

• Tibionavicular part attaches the margin of the plantar calcaneonavicular ligament (spring ligament).
• Tibiocalcaneal part attaches to the sustentaculum tali of the calcaneus bone.
• Posterior tibiotalar part attaches to the medial side and medial tubercle of the talus.
• Anterior tibiotalar part attaches to the medial surface of the talus.

A i.e. The joint is strengthened by deltoid ligament B i.e. It is more stable at dorsiflexed position C i.e. It is a hinge joint

A. i.e. Planter calcaneonavicular ligament 

Calcaneonavicular/ Spring ligament is most important ligament for maintaining the median longitudinal arch of foot but has nothing to do with stability of ankle joint because it is not around ankle joint

A i.e. Anterior Talofibular 

• The most common site of ligament injury is ankle jointQ.
• The most common mode of ankle injury is inversion of planter flexed foot(2.
• Over 90°% of the ankle ligament injury involves lateral collateral ligament usually the anterior tibiofibular ligamentQ.

 Plantar calcaneonavicular ligament

• Spring ligament (Plantar calcaneonavicular ligament) connects the calcaneum with the navicular bone. o However, its principal job is to provide a sling for the talus, to support the head of talus (though it has no attachment to talus).
• This aids in supporting the weight of the body.
• Weaknes or lengthening along this ligament can cause flat foot.