An ankle sprain occurs when the strong ligaments that support the ankle stretch beyond their limits and tear. 

Anatomy

There are two main sets of ligaments that originate from the inside (medial) and outside (lateral) of the ankle.

How common are they?

Acute ankle sprains represented approximately 15% to 17% of all injuries reported. A sprain of the lateral ankle ligament complex is the most common type of ankle sprain, particularly the anterior talofibular ligament.

Further, a history of a previous lateral ankle sprain is one of the strongest risk factors resulting in a re-injury rate of 3.5 times more.

Causes

Ankle sprains are caused by twisting at the ankle past its normal range of motion. 

Following an ankle sprain you may experience:

• Pain
• Swelling
• Bruising
• Tenderness to touch
• Instability 
• Inability to weight bear

Imaging is not often necessary, however in the case of a severe ankle sprain your clinician may request the following:

• X-ray:
  •  This will be used to rule out a broken bone in your ankle or foot. 
• Ultrasound:
  • This scan will show the damage to the ligament tissue.

Grade of Ankle Sprain

Sprains are graded on how much damage has occurred in the ligaments:

• Grade 1 Sprain (Mild):
  • Slight stretching and microscopic tearing of the ligament fibres
• Grade 2 Sprain (Moderate):
  • Partial tearing of the ligament
• Grade 3 Sprain (Severe):
  • Complete tear of the ligament

What next?

Part Two of this article will look at treatment that can help with managing your ankle sprain. 

 

 

Nicole Pereira
Bachelor of Physiotherapy