Do I Need an MRI for a Sprained Ankle?
Updated: 4 days ago
Most sprained ankles do not need an MRI. They usually heal with rest, protection, and exercises. Your doctor may order an MRI if pain, swelling, or a loose, wobbly feeling doesn't get better with treatment, or if they think there may be a bad ligament tear, cartilage damage, or a hidden bone injury.
This guide explains what happens in a sprain, when an MRI may help, how it compares with an X-ray, and what to expect during an ankle MRI.
What is an ankle sprain?
A sprain happens when you roll, twist, or turn your foot beyond its normal range. This stretches or tears the ligaments, the tough bands that connect bones and hold the ankle joint steady. Most sprains affect the ligaments on the outside of the ankle.
Common signs of a sprain include:
Pain around the ankle, especially when you put weight on it
Swelling and bruising
Stiffness or trouble moving the ankle
A pop felt or heard at the time of the injury
A loose or unstable feeling in the joint
How sprains are graded
Doctors often grade sprains by how much the ligament is damaged:
Grade 1 (mild): the ligament is stretched but not torn
Grade 2 (moderate): the ligament is partly torn
Grade 3 (severe): the ligament is fully torn
The grade helps guide treatment. A physical exam is usually the first step in figuring it out.
How most sprains are treated
Many sprains get better with simple care. Doctors often suggest the R.I.C.E. approach: rest, ice, compression, and elevation. More serious sprains may need a brace, a walking boot, or a splint to protect the joint. Rehab exercises help bring back strength, balance, and motion, and can lower the chance of spraining the ankle again. Follow your doctor's plan for your injury.
When do you need an MRI for a sprained ankle?
An MRI is usually not the first test for a sprain. Your doctor may recommend one when:
Pain, swelling, or instability hasn't improved after several weeks of treatment
The ankle keeps giving way or feels unstable
Your doctor suspects a severe or complete ligament tear
More than one ligament may be hurt
There may be damage to the cartilage that covers the ends of the bones
An X-ray is normal, but your doctor suspects a small fracture or bone bruise
You may need surgery and your surgeon wants a detailed look first
Only your doctor can decide if you need an MRI. Get medical care right away if you can't put any weight on your foot, the ankle looks misshapen, or you have numbness or a cold, pale foot.
MRI vs. X-ray vs. physical exam
Each step in checking an ankle injury tells your doctor something different.
Test | What it shows | Limits |
Physical exam | Swelling, tenderness, range of motion, and whether you can bear weight | Can't see inside the joint |
X-ray | Broken bones and alignment | Doesn't show ligaments or cartilage well |
MRI | Ligaments, tendons, cartilage, and bone, including small fractures and bone bruises | Takes longer and costs more than an X-ray |
Doctors often start with an exam and X-ray. If those don't explain your symptoms, or if healing is slow, an MRI can give a more complete picture. MRI does not use ionizing radiation. To learn more about how these tests compare, see MRI vs. CT vs. X-ray.
What an ankle MRI can show
MRI uses a strong magnet and radio waves to make detailed pictures of the inside of the ankle. It can help your doctor see:
Ligament stretching, partial tears, and full tears
Tendon injuries, such as problems with the tendons that run along the outside or back of the ankle
Damage to the cartilage on the ends of the bones
Bone bruises and small fractures that may not show on X-ray
Swelling and fluid in or around the joint
This detail helps your doctor make a treatment plan that fits your injury. If your report uses words you don't know, our guide to ankle MRI terms can help.
How to prepare for an ankle MRI
Preparation is simple:
Arrive a little early to fill out a safety form
Wear comfortable clothes with no metal, or change into a gown if asked
Remove jewelry, watches, belts, and other metal items
Tell the team about any implants, devices, or past surgeries
Tell the team if you are pregnant or could be pregnant
The MRI magnet is very strong, so the safety screening matters. A locker is usually available for your belongings. If you're nervous about the scanner, our tips for handling claustrophobia during an MRI may help.
What to expect during the scan
You will lie on a padded table that slides into the scanner. For an ankle scan, often only the lower part of your body goes into the machine. Your ankle is placed in a coil, a lightweight frame that helps take sharper pictures.
The scanner makes loud tapping and knocking sounds, so you'll get earplugs or headphones. The technologist watches from the next room and can talk with you through a speaker. Try to stay as still as you can so the pictures are clear.
The scan is painless. There is no recovery time, so you can usually go back to your normal activities right away.
After your MRI
A board-certified radiologist reads your images and sends a report to your doctor. At Millenium MRI, results are usually sent to the referring doctor within 24 hours. Your doctor will go over the results with you and talk about next steps. These might include more rest, physical therapy, a brace or boot, or a visit with a foot and ankle specialist.
Frequently asked questions
Can an MRI show a torn ankle ligament?
Yes. MRI can show whether a ligament is stretched, partly torn, or fully torn. It can also show injuries to nearby tendons, cartilage, and bone.
Should I get an X-ray or an MRI for a sprained ankle?
Doctors often start with an X-ray to check for broken bones. An MRI may be ordered if the X-ray is normal but symptoms don't improve, or if a serious soft tissue injury is suspected.
How long after a sprain should I get an MRI?
There's no set rule. Many doctors wait to see how the ankle responds to treatment first. Your doctor will decide based on your symptoms and exam.
Can an MRI show a hidden fracture in the ankle?
Yes. MRI can show small fractures and bone bruises that may not appear on a regular X-ray.
Does an ankle MRI hurt?
No. The scan is painless. You just need to lie still and put up with some loud noises.
Do I need a doctor's order for an ankle MRI?
If you're using insurance, yes. Your doctor's order tells the imaging team which body part to scan and why. If you pay cash (self-pay), no referral is needed at Millenium MRI, and you can call and book directly.
Related reading
Schedule an MRI at Millenium MRI
Millenium MRI has centers in Ocala, Largo, and Tamarac, Florida, and in Jonesboro, Marion, North Little Rock, and Springdale, Arkansas. Our board-certified radiologists and ARRT-certified technologists focus on clear images and a comfortable visit. Same-day appointments are often available, and most patients are in and out in about 35 minutes. We accept most insurance plans, workers' compensation, personal injury cases, and self-pay. Our centers are open Monday through Friday, 9am to 5pm. Call your nearest center or request an appointment online.
This article is for general information and is not medical advice. Talk with your doctor about your specific situation.
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