Your Guide to Understanding Lateral Ankle Sprains

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A lateral ankle sprain is one of the most common injuries that can occur in any situation ranging from daily living to high level sports, and is certainly the most common injury affecting the ankle joint.

While it’s one of the most commonly seen ankle injuries in the clinic, they can be quite severe, and the impact it can create on daily life should not be ignored. With a little bit of education around these types of ankle injuries, they can be managed quite well, allowing you to return to all of your sports and functional activities.

This article is intended to provide you with the information you need in order to understand lateral ankle sprains, develop self-management strategies should you suffer one, and gain the confidence you need to put you in the driver’s seat of your assessment and treatment strategies.

Difference Between Lateral Ankle Sprains and Low Ankle Sprains

Lateral ankle sprains are essentially a subtype of a low ankle sprains, the latter of which occur just below, or around, the medial and/or lateral malleolus.

The malleoli are the bony projections at the bottom of your shin bones on the sides of your ankle. For a lateral ankle sprain, the injury occurs on the outside of the ankle and involve ligaments that attach to the lateral malleolus (bony part at the bottom of the fibula).

Conversely, a medial ankle sprain involves ligaments on the inside of the ankle, many of which attach to the medial malleolus (bony part at the bottom of the tibia).

While medial ankle sprains and lateral ankle sprains are both considered to be low ankle sprains, people often interchange “low” and “lateral” simply because lateral ankle sprains are far more common than medial ankle sprains.

Lateral Ankle Sprain – Mechanism of Injury

The most common mechanism of injury for a lateral ankle sprain is forced ankle inversion, or in other words, rolling the ankle.

Non-contact examples I’ve seen from daily living include, but are not limited to, stepping awkwardly off a curb, slipping on ice, slipping on uneven terrain, etc.

In sports, we often see this happen in non-contact settings when a player is just out of control landing from a jump, stepping on another player’s foot, lack of control and stability with a plant and cut motion, etc.

Additionally, lateral ankle sprains can be secondary to physical contact or other trauma, such as a fall from a height or getting tackled by an opponent, in which case we need to consider the possibility of other ankle injuries as well, such as a different type of sprained ankle or ankle fractures.

What ankle ligaments are injured in a lateral ankle sprain?

One thing many people don’t realize is that a sprain (emphasis on the ‘p’) involves injured ligaments, which are passive elastic-like structures that connect bone to bone, whereas a strain (emphasis on the ‘t’) involves an injured muscle.

In this case, a lateral ankle sprain refers to disruption of the lateral ankle ligaments, which sit on the outside of the ankle. While any ligament can theoretically become injured, there are a few ligaments that are definitely more prone to injuries than others.

The most commonly injured ligament in a lateral ankle sprain is the anterior talofibular ligament (ATFL).

This ligament connects from the anterior aspect of the lateral malleolus to the talus bone, which is one of the main bones of the ankle joint and resists excessive twisting and inversion when the ankle is in a more plantarflexed position (plantarflexion = pointing the foot down or “pressing the gas pedal”).

Rolling your ankle often involves a combination of ankle plantarflexion and ankle inversion, which is why the anterior talofibular ligament (ATFL) is most commonly injured.

There is another lateral ankle ligament that sits very close to the ATFL called the calcaneofibular ligament, or CFL for short.

The calcaneofibular ligament connects from the inferior aspect of the lateral malleolus to the calcaneus bone and mainly helps to resist excessive twisting and inversion when the foot is in a neutral or slightly dorsiflexed position (dorsiflexion = foot pointing up or “toes to nose”).

The CFL is the most lateral ankle ligament, meaning it sits on the side of the ankle joint and almost purely resists excessive ankle inversion. It is common to injure the ATFL and CFL together at the same time.

Also connecting from the tip of the lateral malleolus, but more on the back of the ankle joint, is the posterior talofibular ligament (PTFL).

The posterior talofibular ligament resists backwards motion of the talus relative to the fibula. It’s the strongest lateral ankle ligament of the bunch and not overly prone to injury via more common movements, and therefore it’s more often affected in severe ankle sprains.

Ankle Ligament Anatomy – Lateral and Medial Views of a Right Ankle

In summary, the ATFL is the most commonly injured lateral ankle ligament, followed by the CFL, and then the PTFL. These lateral ankle ligaments can be injured in isolation, or injured together in some combination, which is partially why there is a large spectrum in terms of the severity of an ankle sprain.

How do you know if you have a lateral ankle sprain?

I highly recommend that you seek care from a healthcare professional, e.g. a doctor or physiotherapist, if you suspect you injured any part of your body, a lateral ankle ligament included.

One of the first things a doctor or physio will do when assessing your ankle injury is attempt to rule out any ankle fractures or foot fractures, and this investigation typically occurs prior to stress testing a suspected sprain to a lateral ankle ligament.

We have a full article guidelines for differentiating a sprain vs. fracture, which involves a detailed description of the Ottawa Ankle Rules, so we won’t go into detail in that regard in this article, and will instead focus on ligament sprains with the assumption that a fracture has already been ruled out, either by x-ray or Ottawa Ankle Rules.

When assessing for a sprained ankle, it’s not all about the physical testing. What you report in terms of mechanism of injury, symptoms you are experiencing, and any other medical or injury history can be highly valuable towards understanding the injury.

Subjective findings that may suggest a lateral ankle sprain include, but are not limited to, the following:

  • Mechanism of Injury = rolling or twisting the ankle, contact from an opponent, or other trauma
  • Sensation or sound of a pop on the outside of the ankle or foot
  • Swelling and/or bruising on the outside of the ankle, specifically on, or around, the lateral malleolus
  • Walking with a limp
  • Pain throughout the outside of the ankle at rest, when walking, or when palpated

After gaining the history of your injury and other relevant medical history, the clinician may then perform a series of tests for the ankle joint in the physical examination both specific to a lateral ligament sprain, but also for other injuries that may be present.

Sometimes it can be a little tricky to sort out the extent of the injury involving lateral ligaments, and other times it’s pretty obvious, so the extent of the physical examination can vary. Some specific physical examination findings include, but are not limited to, the following:

  • Pain on the outside of the ankle when moving the ankle passively or actively, particularly in the directions of inversion and/or plantarflexion
  • Tenderness on palpation to the lateral malleolus, ATFL, CFL, or PTFL
  • Swelling and/or bruising on the outside of the ankle
  • Pain with weight bearing creating a visible limp
  • Reduced single leg balance/stability in standing
  • Positive special tests including the anterior drawer test, ATFL stress test, CFL stress test, and/or PTFL stress test. Pain with ligament stress testing, or laxity +/- pain during ligament stress tests especially with a soft end feel, can both indicate a positive test.

Treatment for a Lateral Ankle Sprain

Generally speaking, treatment for a lateral ankle sprain is typically non-surgical, even if a complete ligament tear is suspected, and follows a sequential progression of activity-based treatment to help restore function of the ankle joint.

While there are numerous treatment protocols available online, the time-frame of each treatment phase will vary on the individual and the severity of their injury.

Therefore, when following protocols, it is recommended to think more about meeting specific criteria for progression to the next phase, as opposed to thinking purely about timelines.

For example, a particular phase of treatment may be different between individuals. Some individuals with a less severe injury may be able to begin strengthening on their feet far sooner than those with severe injuries, which is an instance where following strict timelines may not be entirely appropriate.

General Treatment Phases for Lateral Ankle Sprain Rehab

Phase 1 – P.R.I.C.E

Phase 1 of rehab requires you to be kind to yourself, but that doesn’t mean ignoring the issue. In this phase, it’s ideal to follow the PRICE acronym, which stands for:

  • Protection: Avoid exposing you ankle to loads/activities/environments that could aggravate it.
  • Rest: Avoid excessive movement/loads/activities that cause pain and aggravate the ankle.
  • Ice: Applying ice with a layer between the ice and your skin (e.g. a damp towel) for 10-20 mins can help prevent excessive swelling and prolonged inflammation.
  • Compression: This offers a more mechanical avenue to decreasing excessive swelling.
  • Elevation: By keeping your ankle above heart level (e.g. lying on your back with your ankle up on a stack of pillows), you can use the assistance of gravity to assist in the reduction of excessive swelling.
Application of the PRICE Guidelines for Acute Lateral Ankle Sprains

The main reason this is important is because the first part of tissue healing is the inflammatory phase, which normally lasts around 1 to 10 days after injury. Inflammation is typically thought of as being very bad, but in reality, it’s a necessary component to tissue healing, so long as it doesn’t turn into a chronic process.

Many cellular processes are taking place here, including the formation of new blood vessels (angiogenesis), changes to the permeability of vessel walls, inundation of white blood cells and platelets to the injured tissue, etc.

A more simple way of thinking about inflammation is considering it a process whereby the body is cleaning up debris in the injured area and preparing the area for the deposition of new healthy tissue.

This is a necessary part of the healing phase, and by applying the PRICE acronym to your treatment strategy, you will be ensuring that you provide a healthy environment for healing while minimizing the risk of prolonging the inflammatory phase longer than necessary.

When getting back to activities on your feet, it may be advised to wear an ankle brace that offers good ankle support, but this can be guided by your physical therapist.

While ankle bracing can help offer support, this isn’t something you want to completely rely on down the road, which is partially why physical therapy is so important.

In more severe lateral ankle ligament sprains, or especially with high ankle sprains, a walking boot may also be advised. Feel free to check out our information on some of the most common walking boots available.

Phase 2 – Range of Motion (ROM), Proximal Strengthening, and Foot Intrinsics

Usually after a few days, or a bit longer depending on the severity, it is advised to begin active range of motion (ROM) exercises without disrupting the healing of the injured ankle ligament.

The active component is key, as you will be in more control this way and performing a more functional activity, as opposed to static stretching. It is ok to feel some stiffness or mild discomfort when performing these exercises, but it’s best to avoid too much motion that creates pain.

The most caution should be taken when performing inversion, and depending on the state of your injury, your physio may advise avoiding this motion altogether, as this will stretch the ATFL and CFL.

Plantarflexion should also be performed with caution for the same reasons, ensuring not to move to far or rapidly into plantarflexion, although this direction is usually a little less risky. Eversion and dorsiflexion are typically fine to perform.

Common exercises include ankle pumps within a tolerable range, eversion active ROM, tracing the alphabet with your foot within a tolerable limit, and ankle dorsiflexion passive ROM and/or calf stretching as symptoms allow.

While the ankle may not be quite ready to begin strengthening at this point, you can certainly maintain hip and knee strength as you allow your ankle to recover. This is highly recommended, as muscles can decondition quite quickly following injury, especially if you are unable to bear weight for a while.

Important muscle groups to strengthen include the quads, hamstring, glutes, hip adductors, hip flexors, and the core. By maintaining strength in these muscle groups, you will improve your chances of a successful recovery and avoid any risk of setbacks as you get back on your feet.

Similarly, strengthening the small intrinsic muscles of the foot in a manner that doesn’t aggravate the ankle will allow future phases of recovery to be much more effective with less risk of developing separate problems.

Phase 3 – Fundamental Strength and Stability

As range of motion improves and becomes much more comfortable, the next step is to begin restoring ankle strength and stability, which will address the primary problem of lateral ankle instability, and is often done by incorporating more ankle proprioception exercises.

In many cases, initial strengthening involves isolating muscle groups and using a resistance band to strengthen those groups in a safe non-weight bearing fashion.

While simple and admittedly boring, these exercises allow you to safely target the most imperative muscle groups for strength and stability, providing a solid foundation to eventually move on to more functional strengthening.

If weight bearing has been largely avoided up to this point, then a good point to start at is lateral weight shifting in a standing position with light hand support. As soon as safely possible, it’s ideal to move on to single leg stability.

There are many different ways to challenge stability in a single leg stance. For example, changing the surface (barefoot, running shoes, solid surface vs. stack of towels, etc) can offer variety and ultimately optimization of your stability program.

Other techniques to improve ankle stability and proprioception is performing single leg balance with your eyes closed. By removing visual input from the system, your body will now rely more heavily on feedback it is receiving through the ankle joints and muscles without aggravating the lateral ligament injury.

Phase 4 – Basic Dynamic Strength, Stability, and Proprioception

This phase will increase the volume of closed kinetic chain exercises, which are exercises performed with your feet on the ground.

For example, a squat is closed kinetic chain, whereas a seated knee extension is open kinetic chain. Closed kinetic chain exercises inherently demand sufficient strength and stability from the ankle joints, particularly through movement.

In this phase, exercises may start in a double leg stance and progressive to single leg. Similar to the previous phase, altering the environment like the surface you’re standing on can represent another type of progression or adaption to an exercise, which will continue to address any lateral ankle instability.

For example, double leg squats are often a safe starting point (assuming proper technique), and can be progressed to double leg squats on a bosu ball, then single leg squats, then to single leg squats on a bosu ball.

Double leg bosu squat

These activities will demand sufficient strength, and particularly proprioception, to maintain proper form while your center of mass is being displaced over the ankle.

Single leg bosu squat

Phase 5 – Advanced Dynamic Strength, Stability, and Proprioception

This difference between this phase and the previous is that your body will be moving in space to a larger degree. For example, a walking lunge to A-stance exercise or side stepping against a band both represent dynamic strengthening exercises whereby your body is moving in space.

Progressions may include incorporating strategies involving quicker movements or jogging exercises. From there, jumping represents an effective means to further optimize the advanced phase of rehab, as this will combine principles of plyometrics, eccentric control, joint proprioception, and overall functional strength and mobility.

Other activities such as quick feet, ladder drills, and plant + cut drills may be incorporated into your rehab program depending on your task demands, general interests, and resources available to you.

By progressing through all these phases, you can ensure optimal recovery from your lateral ligament injury and at the same time minimize the risk of recurrent sprains or any other ankle injury, while also optimizing your performance as an athlete.


Lateral ankle ligament sprains are extremely common injuries; however, given the severity of an ankle sprain can vary from mild sprains that you consider annoying, to severe sprains that keep you laid up on the couch, it is highly recommended to seek assistance from a doctor or physiotherapist in order to ensure a safe and effective recovery.

Rehab programs for lateral ankle ligament sprains generally progress through phases of protection, to restorations of range of motion and strength, to advanced stability and proprioception. This will not only help with recovery for the current injury, but will help prevent recurrent ankle sprains and chronic ankle pain in the future.

Lastly, progression through these phases should be guided by achievement of various objective checkpoints, rather than adopting a “one-size-fits-all” approach based on black and white timelines, which again, is why we recommend consulting with a physical therapist in person for any lateral ankle injury.


Larkins LW, Baker RT, Baker JG. Physical Examination of the Ankle: A Review of the Original Orthopedic Special Test Description and Scientific Validity of Common Tests for Ankle Examination. Arch Rehabil Res Clin Transl. 2020 Jul 8;2(3):100072. doi: 10.1016/j.arrct.2020.100072. PMID: 33543095; PMCID: PMC7853358.

Lee DR, Choi YE. Effects of a 6-week intrinsic foot muscle exercise program on the functions of intrinsic foot muscle and dynamic balance in patients with chronic ankle instability. J Exerc Rehabil. 2019 Oct 28;15(5):709-714. doi: 10.12965/jer.1938488.244. PMID: 31723561; PMCID: PMC6834706.

Rakshatha Kabbaligere, Beom-Chan Lee, Charles S. Layne. Balancing sensory inputs: Sensory reweighting of ankle proprioception and vision during a bipedal posture task. Gait & Posture. Volume 52, 2017, Pages 244-250, ISSN 0966-6362,

Wang H, Yu H, Kim YH, Kan W. Comparison of the Effect of Resistance and Balance Training on Isokinetic Eversion Strength, Dynamic Balance, Hop Test, and Ankle Score in Ankle Sprain. Life. 2021; 11(4):307.


The content here is designed for information & education purposes only and is not intended for medical advice.



John Schipilow

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