by Dr. Emily Splichal, DPM MS
Whether it is an accidental misstep off the sidewalk or a major twist of the ankle during a run, most ankle injuries involve the ankle ligaments and are referred to as an ankle sprain.
Ligaments are bands of connective tissue which connect bone to bone. The ligaments of the ankle run from the lower leg (tibia and fibula) to the foot (talus). The ligaments on the inside or medial aspect of the ankle are large, flat and closely adhered to the bone whereas the ligaments on the outside of the ankle or lateral aspect are smaller, thinner and allow a much greater range of motion.
This difference in ligament structure means that lateral ankle sprains or an injury to the outside of the ankle joint occur more frequently and make up 85% of all ankle sprains.
Mechanism of Injury
Due to the mechanics of the ankle joint, most ankle sprains occur when pushing off to take a step or coming down from a jump. This means that the ankle is in a plantarflexed or toes down position when the injury occurs. This plantarflexed and lateral movement can stretch and tear the lateral ankle ligaments and is referred to as an inversion ankle sprain.
Depending on the severity of the sprain or injury to the ligaments, all ankle sprains can be classified into 3 grades:
- Grade 1 (Mild). The ligament fibers stretched slightly or there is a very small tear.
- Grade 2 (Moderate). The ligament is partially torn, but it isn't a complete tear.
- Grade 3 (Severe). The ligament is torn completely.
Symptoms of ankle sprains can vary depending on grade of ankle sprain however the most common symptoms include:
- Pain to the lateral ankle, especially when putting weight on your ankle
- Tenderness to the touch
- Difficulty walking
Treatment of Ankle Sprains
The acute ankle sprain is typically managed conservatively and based on severity or grade with general guidelines as follow:
- Grade 1: Use R.I.C.E. (rest, ice, compression and elevation), typically resolves in a few days.
- Grade 2: Utilize the R.I.C.E. guidelines, typically resolves in a few weeks.
- Grade 3: May require ankle brace and at times crutches. Chronic instability can occur in 20% of cases.
Due to the varied nature of ankle sprains it can be difficult to diagnose or grade an ankle sprain without imaging, therefore it is always good practice to see a medical professional who will decide the need for an X-ray, or in certain cases an MRI or Ultrasound.
Chronic Ankle Instability
20% of ankle sprains will go on to develop chronic ankle instability or the recurring giving way of the ankle. Research has shown that these injuries not only have a disruption in the ligament integrity but also a delay in the proprioceptive or neurological feedback in the ankle.