Updated: Apr 24
This is probably one of the most common lower limb injuries seen in the clinic and also one of the post poorly self managed injuries we see.
What seems like a relatively simple injury can cause alot of trouble further down the line if not managed well.
How do we sprain the ankle ?
The most common mechanism is when the ankle rolls underneath us which is commonly seen in;
Sudden changes of direction.
Poor landing mechanics when jumping
Landing on an uneven surface or object.
Slipping on unstable or slippery surface.
What is injured when we sprain the ankle ?
These mechanisms of these injuries are forced plantar flexion and inversion of the ankle which puts stress through the capsulo-ligamentous structures of the outside of the ankle:
Anterior talo fibular ligament, (ATFL).
Anterior tibio fibular ligament, ligament between the fibula and tibia.
Calcaneo fibular ligament.
Syndesmosis, The tissue between the fibula and tibia.
Here's a good video demonstrating movements. available at the ankle.
The ATFL prevents forward movement of the ankle from the tiba and fibula complex as well as preventing the inversion and internal rotation of the ankle joint.
The strain in the ATFL increases the more you point your foot away from the body, this movement is known as plantar flexion.
It is also the weakest of the three ligaments in the outside of the ankle and this is why it is the most commonly injured ligament in the classic inversion/plantar flexion mechanism.
The CFL restricts excessive supination/rotation of both the ankle and is a stronger structure than the ATFL. It is more commonly injured if the ankle is forcibly inverted when in a neutral to dorsiflexed position.
CFL injuries are usually seen in more significant ankle injuries than simple sprains.
Are there different grades of ankle ligament injury ?
Traditionally ankle injuries were graded as such :
Grade I injuries:
Incomplete tear of the ATFL,
Little swelling or tenderness,
Minimal or no functional loss.
Some loss of joint movement.
No mechanical instability of the joint.
Grade II injury:
Complete tear of the ATFL and partial tear of the CFL. ligaments.
Moderate pain, swelling, and tenderness over the involved structures.
There is some loss of joint movement.
Mild to moderate instability.
Grade III injury:
Complete rupture of the ATFL and CFL.
Marked swelling, hemorrhage, and tenderness.
There is loss of function.
Abnormal motion and instability of the joint.
To look at how to treat ankle Ligament injuries to get the best result and if you need an x-ray click here
If you need help with an ankle injury you can book in to see one of us here