Why does a sprained ankle swell?

Swelling commonly occurs after an ankle injury in the inflammatory phase of healing. A more formal term for this specific type of swelling is “exudate edema”, whereby “exudate” refers to the accumulation of fluid due to increased vascular permeability, and “edema” is simply the latin word for swelling.

While it may not seem intuitive for the body to want to increase the permeability blood vessels, this actually allows for a greater amount of white blood cells to enter the damaged tissue and begin cleaning up the area.

Therefore, while swelling can be uncomfortable and unsettling, it’s a natural byproduct of the inflammatory phase of tissue healing.

How long does a sprained ankle stay swollen?

Unfortunately, there is no definite answer to this, as it depends on the severity of injury, comorbidities, access to educational resources and rehab, and daily tasks that are required while you recover from your ankle sprain.

That said, after an acute ankle sprain, you should start to notice the swelling beginning to subside after 2-3 days with continued reduction from there. Given this is a key component to the inflammatory phase of healing, it’s common to see swelling last up to a week or two in more severe cases.

If your ankle is still swollen after approximately 1 week, I wouldn’t be too concerned, especially if you are noticing improvement in other areas, such as comfort, ability to tolerate weight bearing, improved range of motion, and the swelling isn’t increasing.

Patients will occasionally experience a temporary recurrence of mild localized swelling further along in the rehab process as they begin more weight bearing activities, or if they happen to aggravate their ankle, but this would have been preceded with a reduction in swelling

On the other hand, if your ankle is still swollen after 4 weeks for example, I would be a fairly concerned, especially if your ankle swelling and overall function (or lack thereof) is still interfering with your life. If there is no change tot he swelling after many weeks, I would play it safe and seek a second opinion from another doctor or physiotherapist, just in case something was missed the first time around.

In the meantime, one thing you can do to help manage the swelling and prevent secondary tissue damage during the inflammatory phase is to apply ice to your ankle sprain.

Icing a Sprained Ankle

Applying ice to a sprained ankle, which is more formally termed “cryotherapy”, is one of the most common recommendations to reduce pain and swelling in the acute stage of an ankle sprain (Bleakley et al. 2006), and to reduce secondary tissue damage; however, this requires the correct application of ice, as well as appropriate situations.

Adverse effects of ice can include skin rash/allergic reaction (most common), increased pain, frostbite, and general tissue damage. For this reason, we will provide some examples of how ice is generally applied in in a safe manner, as well as some situations when one would want to avoid applying ice to a sprained ankle.

When to Avoid Ice

There are numerous precautions and contraindications to using ice as a form of treatment for ankle sprains. These include, but are not limited to, the following:

• Active Deep Vein Thrombosis (DVT)
• Chronic wound(s) in the area
• Cold hypersensitivity conditions, such as Reynaud’s disease.
• Impaired circulation in the area
• Impaired sensation in the area
• Hemorrhagic conditions
• Skin reactions to cold, i.e. cold urticaria
• Impaired cognition or ability to communicate

How to Test Sensation for Safe Application of Ice

Testing for protective sensation is always recommended especially if you suspect you have altered sensation from your injury or any other condition. There are many different types of sensation, but in this case, it’s pretty simple.

To ensure you can receive proper feedback about how your skin and other soft tissue is responding to ice, you can simply trial applying heat and ice in a random order and test your ability to differentiate the two.

For example, in the clinic, we have little vials of water that we fill with cold and warm water. To ensure adequate protective sensation, we typically get the patient to close their eyes and tell us if they feel cold or warm as we touch a single vial of water to their skin in and around the area of intended application.

We do this about 10 times with a random order of hot vs. cold. If the patient is able to correctly identify 9 or 10 of the vial temperatures (at least a 90% success rate), then we can be confident they have intact protective sensation.

This, combined with the absence of any contraindications or major precautions, will suggest that cryotherapy is a safe modality for the patient if they are educated on adverse responses and how to apply the ice correctly.

How Long to Ice a Sprained Ankle

This will depend on method of application. Generally speaking, you want to ensure that the skin and underlying tissue cools sufficiently, but not to the point of completely numbing the area.

No matter what type of application, it’s highly recommended to frequently check the skin for excessive redness, and allergic reaction such as hives, skin damage, and to generally test the level of remaining sensation.

We have listed some more specific guidelines for different types of cryotherapy; however, please keep in mind that you should always check with a healthcare professional who can see you in person, particularly if it’s the first time applying ice.

Ice Massage: 10 Minutes

When icing your sprained ankle via ice massage, it’s a good idea to start out with the notion “less is more”. This is one of the most targeted and aggressive forms of cryotherapy and involves the direct application of ice on skin.

For example, some clinicians may pack some crushed ice into a small paper cup, kind of like a snow cone, and then hold the cup as they place the ice directly on the skin and massage in small circles over the affected area. This is more appropriate for small areas of injury and can be very intense for the patient, sometimes to the point where it cannot be tolerated for more than a few minutes.

If tolerable, applying ice massage for 10 minutes is effective, assuming it’s been deemed safe and the skin is constantly being checked.

Ice Packs: 20-30 Minutes

Ice packs represent the most common way to ice a sprained ankle at home. This is less intense than an ice massage, again assuming correct application.

In this case, it’s highly recommended to include an insulating layer, even a damp cloth, between the skin and the ice pack, especially if it’s a plastic gel pack. This may take a little longer for the ice to take effect, but it will help avoid any pain and will minimize the risk of adverse effects.

Generally speaking, 20-30 minutes as a good amount of time to leave an ice pack on. One thing to keep in mind is that you won’t be able to see the skin under the ice pack, so it’s very important to constantly check the skin and ensure the ice is evenly distributed.

Cold Bath Immersion: 20 Minutes

For the purpose of this article, we are referring to placing the lower leg into an ice bath, not the entire body. This typically feels colder than an ice pack, and as such, may be fairly uncomfortable depending on the exact temperature.

One benefit to this method of cryotherapy is the ability to perform movements or exercises while immersed. Conversely, one drawback is that the affected limb is usually in a dependent position, meaning it’s highly unlikely you can elevate and compress at the same time.

Cryo Cuffs: 15-20 Minutes

Cryo Cuffs are usually made of nylon and are wearable devices that wrap around the affected limb. They are really common for ankles, knees, shoulders, and elbows. The cuff is attached to a cooler that contains cold water.

The cooler either hangs above the patient to allow gravity to deliver the cold water, or some more advanced devices continuously circulate the water throughout the cuff and a cooling system to maintain a consistent temperature.

Manufacturers often recommend keeping the water temperature at approximately 15 deg C / 59 deg F, but there can be a little wiggle room here depending on how long the cryotherapy is applied for and the desired effect.

Personally, while they take a bit of work, these are my favourite, especially for post-surgical recovery (e.g. post-op ACL) or acute ankle sprains, as they provide a widespread distribution of cryotherapy in a very comfortable manner.

Ice for an Acute Ankle Sprain – Recent Evidence

Applying ice to an acute ankle sprain for the for purpose of pain and swelling management has long been indicated in physiotherapy settings. Previous clinical practice guidelines have typically supported the use of the R.I.C.E protocol in the acute stage of injury; however, recent guidelines have since been modified to be a little more specific.

For example, Vuurburg et al. (2018) published an update to an evidence-based clinical practice guideline suggesting that there is insufficient evidence that ice alone will results in statistically significant difference in rehab outcomes, and rather, the R.I.C.E. principle should be used in combination with other forms of treatment, namely exercise-based treatment.

This was supported by a systematic review conducted by Miranda et al. (2018) that cited a lack of conclusive evidence to support the use of ice alone in treating swelling for an acute ankle sprain. As such, they discussed the need for more high quality randomized control trials (RCT’s) to investigate the effects of various form of cryotherapy on acute ankle sprains specifically.

Summary

Cryotherapy, or the application of ice, is a commonly recommended method to facilitate the reduction of swelling in acute ankle sprains. Timelines for application of ice will vary depending on method used, area of application, and potential precautions/contraindications.

Cryotherapy is typically more effective in the inflammatory phase of healing, and more recent evidence suggests this should be combine with other forms of treatment, for example, exercise-based treatment and the other components of the P.R.I.C.E principle.

For more information, your local doctor or physiotherapist should be able to recommend specific guidelines based on a physical assessment of your ankle sprain.

References

Bleakley CM, McDonough SM, MacAuley DC. Cryotherapy for acute ankle sprains: a randomised controlled study of two different icing protocols. British Journal of Sports Medicine 2006;40:700-705.

Miranda JP, Silva WT, Silva HJ, Mascarenhas RO, Oliveira VC. Effectiveness of cryotherapy on pain intensity, swelling, range of motion, function and recurrence in acute ankle sprain: A systematic review of randomized controlled trials. Phys Ther Sport. 2021 May;49:243-249. doi: 10.1016/j.ptsp.2021.03.011. Epub 2021 Mar 26. PMID: 33813154.

Vuurberg G, Hoorntje A, Wink LM, et al. Diagnosis, treatment and prevention of ankle sprains: update of an evidence-based clinical guideline. British Journal of Sports Medicine 2018;52:956.

Disclaimer:

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