What is a lateral ankle sprain?

There is sprain of the lateral ligaments most commonly the Anterior talofibular ligament (ATFL). We used to think about lateral ankle sprains especially of the ATFL always occuring with inversion and planter flexion but the plantar flexion is not actually necessary for the injury. It occurs with a inversion ( mean peak angle of 67.5 °) +/- rotation and / or plantar flexion.

If you want to learn more about this topic, you can watch Marc Surdyka lecture here:

Click here

Why does it occur?

1. There is this inversion at initial contact during gait which can be a contributing factor.

2. The medial malleolus is less distal. So there’s going to be less of a restraint from the medial malleolus as it relates to ankle sprains.

3. There is also a ligamentous restraint, i.e the deltoid ligament is much stronger than the lateral ligaments.

Who gets it?

It’s the most common injury. It can occur in anyone, can be general population, it can be athletes of all levels, high school, collegiate, professional. Occurs more in indoor and court sports and then more so in competition than practice. It also occurs in military personnel.

Types of ankle sprains

Grade I is a partial tear of the ATFL.

Grade II would be a complete rupture of the ATFL and partial CFL.

Grade III  would be complete rupture of both, the ATFL and CFL.

Chronic ankle instability and ankle sprains

A previous ankle sprain increases the risk of a subsequent ankle sprain and up to 40% of people develop CAI after lateral ankle sprain. This is an indication of how important rehab is and It’s just not one of those things that people can walk off and get better.

If you want to learn more about this topic, you can watch Marc Surdyka lecture here:

Click here

Sources:

1. 'Simplifying the foot and ankle' lecture by Marc Surdyka