What are the primary ankle ligaments that limit EverSion at the ankle
The correct answer and explanation is:
Primary ankle ligaments that limit eversion at the ankle:
- Deltoid ligament (medial collateral ligament)
Explanation:
The ankle joint is stabilized by several ligaments that prevent excessive movements. When discussing eversion (the movement of the sole of the foot outward, away from the midline), the primary ligaments involved in limiting this motion are found on the medial (inside) side of the ankle.
The key ligament responsible for restricting eversion is the deltoid ligament, also known as the medial collateral ligament of the ankle. It is a strong, broad, triangular ligament complex that attaches from the medial malleolus of the tibia to several tarsal bones (the talus, navicular, and calcaneus).
The deltoid ligament has multiple components, including:
- The tibionavicular ligament
- The tibiocalcaneal ligament
- The anterior tibiotalar ligament
- The posterior tibiotalar ligament
Because eversion forces stress the medial side of the ankle, the deltoid ligament is taut and resists this outward motion, preventing the foot from rolling excessively. This protection is crucial because excessive eversion can lead to sprains or injury, especially since the medial side of the ankle is not as commonly injured as the lateral side.
Why lateral ligaments don’t limit eversion:
The lateral ligaments of the ankle (anterior talofibular ligament, calcaneofibular ligament, and posterior talofibular ligament) primarily resist inversion (inward rolling of the foot), not eversion. Inversion sprains are far more common, which is why lateral ligaments are more often injured.
Summary:
- Eversion is resisted mainly by the deltoid ligament on the medial ankle.
- This ligament complex is strong and broad, providing medial ankle stability.
- The lateral ligaments resist inversion, not eversion.
- Understanding this is important clinically for diagnosing ankle sprains and deciding on treatment.