Fractures and trauma
Ankle Sprain (Sprained Ankle)
In short
An ankle sprain is a stretch or tear of the ligaments that support the ankle, usually after the foot rolls inwards. Nearly all sprains heal without surgery: protection, rest, ice, compression and elevation in the first days, followed by early movement, tape or a brace, and balance and strength exercises. Most people feel clearly better within about two weeks; full recovery and return to sport can take weeks to months depending on the severity.
What is an ankle sprain?
An ankle sprain happens when the strong ligaments that hold the ankle joint together are stretched beyond their normal limits and partly or completely torn. Most sprains occur when the foot rolls inwards and affect the ligaments on the outer side of the ankle; the ligaments on the inner side are injured less often [1].
Sprains are graded by severity. In grade 1 the ligament is only stretched and symptoms are mild. In grade 2 there is a partial tear, moderate swelling and slight looseness. In grade 3 the ligament is completely torn, pain is marked and the ankle feels unstable [1].
What are the symptoms?
How strong the symptoms are depends on how badly the ligaments are damaged. Common complaints include [1][2]:
- Pain, especially when standing or moving
- Swelling and bruising on the outer side of the ankle
- Tenderness to touch
- Difficulty putting weight on the foot
- A feeling that the ankle is giving way
Causes and risk factors
A sprain usually happens when the foot twists while walking on uneven ground, during a fall, or in sports that involve jumping and sudden changes of direction [1]. Taking part in certain sports raises the risk of spraining an ankle [3].
Poor balance, naturally loose ligaments, unsuitable footwear and a previous sprain are the main risk factors for a new sprain [1].
How is it diagnosed? Do I need an X-ray?
The diagnosis is usually made by examination. The doctor checks swelling, tender spots, how far the ankle moves and how stable the ligaments are [1].
Not every sprain needs an X-ray. A simple checklist called the Ottawa ankle rules looks at tenderness over specific bone points and whether the person can take a few steps. It rules out a fracture with high reliability and reduces unnecessary X-rays [5]. If a fracture is suspected, an X-ray is taken; stress X-rays or an MRI scan may be used when ligament or cartilage damage is suspected [1].
The degree of ligament damage is judged more accurately by an examination done four to five days after the injury, once pain and swelling have settled [3].
Treatment without surgery
For the first two to three days, protection, rest, ice, compression with an elastic bandage and elevation are recommended. Ice should be wrapped rather than placed directly on the skin and used for short periods every few hours. Heat, alcohol and massage are best avoided during this early phase [2].
A short period of immobilisation can ease pain and swelling, but the evidence shows better results from early movement and the use of tape or a brace together with an exercise programme, rather than a long time in a cast [3][4].
As pain starts to ease, gentle movement is encouraged to stop the ankle from stiffening; the pace of the exercises is best agreed with a doctor or physiotherapist [2].
Anti-inflammatory painkillers can reduce pain and swelling, but they have possible side effects and may affect healing, so they should be used on medical advice [3][4].
Rehabilitation usually has three phases: first controlling pain and swelling with protected weight-bearing, then range-of-motion, strength and balance work, and finally advanced strengthening, balance (proprioception) training and a gradual return to sport [1]. Supervised exercise programmes are preferred over passive treatments [3].
When is surgery needed?
Almost all ankle sprains heal without an operation [1]. Surgery is considered for people whose symptoms continue and whose ankle keeps giving way despite a thorough, well-followed exercise programme [3]. In that case, problems inside the joint can be treated by arthroscopy, or the damaged ligaments can be repaired or reconstructed [1].
How long does recovery take?
Most people feel clearly better within about two weeks. Returning to demanding activities such as running can take up to eight weeks, and severe sprains may take months [2].
Stopping rehabilitation too early is the main reason an ankle stays chronically unstable [1]. Wearing a brace and doing balance and coordination exercises help prevent another sprain [3][4], and exercise-based rehabilitation lowers the risk of re-injury [4].
To help prevent sprains, it is advised to warm up well before exercise and sport, strengthen the muscles around the ankle, wear supportive shoes and take care on uneven ground [1]. For people who have sprained an ankle before, there is strong evidence that wearing a brace during sport helps prevent another sprain [4].
When to see a doctor urgently
Go to an emergency department without delay in the following situations, as they may point to a fracture, dislocation or a problem with blood supply or nerves [2]:
- A crack or snap was heard at the time of injury
- The ankle looks deformed or out of shape
- Numbness, tingling, coldness, or a blue or grey colour in the foot
- You cannot put any weight on the foot
- Pain and swelling keep getting worse or do not improve with home care
Frequently asked questions
+How long does a sprained ankle take to heal?
With mild and moderate sprains most people feel better in about two weeks. Returning to demanding sports such as running can take up to eight weeks, and severe ligament tears may take months [2].
+Do I need an X-ray for a sprained ankle?
Not always. The Ottawa ankle rules check tenderness over specific bone points and the ability to walk, and reliably rule out a fracture; if any rule is positive, an X-ray is taken [5].
+Does a sprained ankle need a cast?
Usually not. Brief protection can ease pain, but early movement with tape or a brace plus an exercise programme gives better results than a long period in a cast [3][4].
Sources
- [1]Sprained Ankle — American Academy of Orthopaedic Surgeons (OrthoInfo).
- [2]Sprains and strains — NHS (nhs.uk), 2024.
- [3]Diagnosis, treatment and prevention of ankle sprains: update of an evidence-based clinical guideline — British Journal of Sports Medicine (Vuurberg G, et al.), 2018.
- [4]Treatment and prevention of acute and recurrent ankle sprain: an overview of systematic reviews with meta-analysis — British Journal of Sports Medicine (Doherty C, et al.), 2016.
- [5]Accuracy of Ottawa ankle rules to exclude fractures of the ankle and mid-foot: systematic review — BMJ (Bachmann LM, et al.), 2003.
This article is general information and does not replace an examination or personal medical advice. In an emergency, go to the nearest emergency department.