Updated: May 5, 2022
Sprained ankles are one of the most common medical conditions in the United States. In fact, research by Herzog, et al. shows that there are estimated to be 2 million ankle sprains in the United States each year. This may even be a significant underestimate because numbers are based on emergency room visits, which do not take place for many sprained ankles. Interestingly, half of the ankle sprains treated in emergency departments in the United States were not from sports participation. So, if you think that you are completely safe from a sprained ankle because you do not play sports, think again!
Let’s take a look at the anatomy of the ankle. The image below shows the lateral or outside of the ankle. Pay particular attention to the three ligaments that are shown: the anterior talofibular ligament, posterior talofibular ligament, and the calcaneofibular ligament.
When you sprain your ankle, it typically involves a rolling motion, usually with your ankle rolling outwards.
This puts significant stress on the outside of your ankle, which is mainly supported by the three ligaments shown above. Stress can cause stretching of the ligaments which can ultimately lead to partial or complete tearing of the ligaments. We have a classification system of three grades for ankle sprains highlighted in the image below from the American Academy of Family Physicians.
You can see an illustration of the various grades of ankle sprain. Image A shows a Grade 1 sprain, which involves stretching of the anterior talofibular ligament (ATFL) and the calcaneofibular ligament (CFL). Image B shows a Grade 2 sprain, which involves a partial tear of the ATFL and stretching of the CFL. Image C shows a Grade 3 sprain, which involves a full tear or rupture of the ATFL, a rupture of the CFL, and partial tearing of the posterior talofibular and tibiofibular ligaments. It is important to understand what is going on at your ankle on an anatomical level so that you can understand the goals of recovery and treatment.
A vast majority of ankle sprains are on the outside, but occasionally medial (inner) ankle sprains do occur. In this case, there is a single large ligament on the inside of your ankle known as your deltoid ligament that provides most of the support. Symptoms are typically similar as is treatment. Swelling, bruising, etc. will typically be localized to the inside of the ankle.
Did I Sprain My Ankle?
The key to managing a sprained ankle is knowing if you actually have an ankle sprain! The first step is to rule out a more serious injury such as a fracture. The Ottawa ankle rules were created as guidelines for physicians to determine if x-rays are needed for an ankle injury. They were developed because it was found that many unnecessary x-rays were being performed for injuries that were clearly not fractures.
The rules are simple and state that an x-ray should only be performed if someone has one of these characteristics:
Bone tenderness along the last 6 cm (2.5 inches) of the tibia or medial malleolus
Bone tenderness along the last 6 cm (2.5 inches) of the fibula or lateral malleolus
An inability to bear weight for four steps
Basically, if it does not hurt along the last 2.5 inches of either lower leg bone or the bump of bone on the inside of your ankle and you are able to walk 4 steps then you probably do not have a fracture. This is not a hard and fast guideline and if there is any doubt please see a medical professional. The worst outcome is an undiagnosed fracture that worsens over time without proper treatment.
If you do not fit any of those criteria, then you probably sprained your ankle. Sprains can take on many forms regarding pain, swelling, and weakness.
However, bruising may not occur at all depending on blood vessel damage. Typically, some weakness may be present due to damage to the muscles that run along the outside of your ankle. You can test for this by resisting eversion, or the pushing of your foot outwards. If this is painful, then there is a chance of a sprain. You can also gently try to invert your foot, by pushing it inwards. If this is painful as well, then you probably have a sprain. Theoretically, if you have a grade 3 sprain involving tearing of ligaments, then your ankle should move into significant inversion due to lack of resistance from the ligaments, but this is often not the case. Your body will instinctively guard the area and it will be painful to move, limiting your movement. Also, swelling can occur rapidly in the ankle which will impede movement as well.
How Long Does an Ankle Sprain Last?
How long an ankle sprain lasts is difficult to determine as it depends on the individual. However, general guidelines state that:
Grade 1 sprains typically take 2-3 weeks to recover
Grade 2 sprains typically take 4-6 weeks to recover
Grade 3 sprains can take a few months and may require surgery
Once again, these timelines are dependent on the individual and what level of activity in which they participate. A basketball player has no option but to run and jump on the court, while a baseball player may just be able to hit and have someone run for them. Also, a beach volleyball player will have a tougher time returning because they play in bare feet, while a basketball player can tape their ankle and wear a more supportive shoe.
A very common question involves whether you should walk on a sprained ankle. In general, walking depends on your injury severity and tolerance level. We will talk in the next section about rehabilitation, but movement is generally a good quality for blood flow and healing. If you have sharp pain while walking, then it should be avoided, but if there is only a dull ache it may be beneficial to speed up healing. However, walking should not be for a long time, only enough to get your blood flowing and loosen up the ankle. Gradual progression of walking can be beneficial, but too much can delay healing.
Ankle sprains can also have a compounding effect. There are some people who have hypermobility and joint laxity to begin with, typically younger females. Your first ankle sprain takes a while to recover, but there may not be a full healing of the ligaments. Some microtears may still exist along with greater stretching of the ligament. Physical therapy should strengthen the tissues around the ligaments to allow for support, but your ankle does not have the same integrity that it once did. Hypermobile joints only exacerbate this problem. If you were to sprain your ankle again, then the tissues would be stressed even further, creating more laxity. Recurring ankle sprains can lead to a condition known as chronic ankle instability. This means that your ligaments are not providing the support necessary to prevent damage, and you are at an increased risk of recurrent sprains.
Chronic ankle instability can be treated non-operatively with aggressive strengthening of the surrounding tissue, but it can require surgery. The surgeon typically tightens the ligaments to regain some of that helpful tension to prevent sprains. Lengthy physical therapy and a gradual return to activity is required after this surgery, but it is essential to ensure the success of the procedure.
Ankle Sprain Rehab
Rehabilitation for an ankle sprain has come a long way over the years. As I previously mentioned, the common consensus is that early motion and loading is crucial to recovery. Previously, the RICE protocol was advocated by medical providers including Rest, Ice, Compression, and Elevation. Unfortunately, some providers still espouse this idea even though research points to the idea that it actually delays recovery and healing.
The purpose of the RICE protocol is to decrease swelling and inflammation, which is a backwards way of looking at your body. Inflammation carries healing proteins that fix damaged tissue, so why would you want to delay it? Our bodies are designed to fix themselves whenever possible, and swelling is part of that process that we should embrace. If we want to decrease swelling as quickly as possible, then more movement is helpful because muscle activation creates a pump to propel swelling back to the body via the lymphatic system. You want to take out the trash created by the healing proteins, you do not want to prevent the proteins in the first place. Hopefully this concept makes sense and I credit Gary Reinl with Marc Pro for popularizing it. The Marc Pro is a product that we use frequently with our injured athletes because it speeds healing and improves our outcomes significantly!
Another important point that is counterintuitive to a lot of people’s idea of recovery is that ankle sprains should not be stretched aggressively. Light range of motion i