Knees are one of the most commonly injured joints, and sprains are a common injury. They happen when something forces ligaments in your knee to stretch too far or tear. Sports injuries and falls cause most sprained knees. You’ll probably be able to manage your symptoms with at-home treatments, but you should visit a healthcare provider to get the injury diagnosed.
Knee sprains are injuries that happen when ligaments in your knee joint stretch too far or tear.
Ligaments are bands of tissue-like ropes that hold your muscles and bones together and prevent them from moving too far. Ligaments also make sure your joints only move in the direction(s) they’re supposed to.
Visit a healthcare provider if you have pain or swelling in your knee — or if it’s hard to move or use your knee (especially if you experience an injury or fall).
There are four knee ligaments in your knee joint, including your:
It’s more common to sprain collateral ligaments (your MCL or LCL), but you can sprain any ligament — including multiple ligaments during the same injury.
Knees are one of the most commonly injured joints. Sprains are common injuries, especially among athletes.
The most common sprained knee symptoms include:
Anything that forces your knee to move farther than its natural range can cause a sprain. This can happen in any direction, including forcing your knee to bend or flex, or to twist side-to-side more than it should.
The most common sprained knee causes include:
Anyone can sprain their knee, but athletes and people who do physical work are more likely to. Athletes who play sports that make you stop, twist or change direction suddenly have a higher risk, including:
Exercise habits that can increase your knee sprain risk include:
Playing a sport that stresses your knee joints year-round with no off-season or time to rest and recover.
A healthcare provider will diagnose a sprained knee with a physical exam. Your provider will examine your injured knee. They’ll check your range of motion (they might compare it to your other, uninjured knee).
Tell your provider when you first noticed symptoms, especially if you know exactly when the injury happened or what caused it.
Your provider might have you perform a few clinical tests during your physical exam. These tests are physical movements or positions that can help diagnose or rule out other kinds of injuries. Your provider can administer these tests without any special equipment. They’ll tell you to lie down, sit or stand in a specific position and will then move your knee.
Your provider might use imaging tests to take pictures of your knee joint and the tissue around it. Your provider might use:
Healthcare providers grade knee sprains based on how damaged your knee ligaments are:
You can probably manage sprained knee symptoms at home. But visit a healthcare provider first so they can diagnose the injury and make sure nothing else inside your knee is damaged.
The most common treatment for knee sprains is the R.I.C.E. method:
Over-the-counter NSAIDs (aspirin or ibuprofen) or acetaminophen can reduce pain and inflammation. Talk to your provider before taking over-the-counter (OTC) pain medication for longer than 10 days.
You might need to wear a brace that supports your knee and holds it in place. You may also need crutches while your knee heals. Your provider might suggest physical therapy to prevent stiffness and improve your range of motion.
It’s rare to need surgery after a knee sprain. You may need surgery if you have a severe sprain or other injuries like a bone fracture (broken bone).
You should feel better gradually after you start treating a sprained knee. It might take a few weeks for your symptoms to improve.
Ask your provider how much you can use your knee while you’re recovering. Don’t start using your knee again unless your provider says it’s safe, even if it feels better. If you put stress on your knee ligaments before they’ve fully healed, there’s an increased chance you’ll re-injure them or make the original sprain worse.
There might not be any way to prevent a knee sprain, especially if you’re an athlete. But there are ways you can lower your risk. During sports or other physical activities:
Follow these general safety tips to reduce your risk of an injury:
Knee sprains are usually temporary injuries. Most sprains don’t affect your ability to play sports or stay active after your provider says it’s safe to resume playing or training.
Spraining a knee once might make it more likely to injure that knee again in the future (especially if you had a moderate or severe sprain). Ask your provider what you can do to reduce your risk of future sprains.
It usually takes at least a few weeks for a sprained knee to heal. More severe sprains can take up to a few months. Your healthcare provider will tell you what to expect.
Ask your provider which activities and motions are safe to do while you’re recovering. They’ll tell you when it’s safe to return to intense physical activity using your knee.
Visit a healthcare provider if you’ve experienced an injury and have knee sprain symptoms. Talk to your provider if your symptoms aren’t improving after a few days of treatment (or if they’re getting worse).
Go to the ER if you experience any of the following:
Knee sprains and knee ligament tears are similar injuries. The difference is how severely your ligaments are stretched or damaged.
Grade 1 and grade 2 knee sprains mean your ligaments are stretched or partially torn, but not completely. A grade 3 knee sprain is a complete tear, meaning the injury stretched your ligament far enough to break it apart.
Grade 3 knee sprains and ligament tears are the same injury, and can include:
Visit a healthcare provider if you’re experiencing pain, swelling or can’t move your knee. They’ll diagnose the injury and suggest the right treatments.
A note from Cleveland Clinic
Knee sprains are painful, and it can be scary to know something damaged your knee joint. They’re a common (and frustrating) risk for anyone who plays a sport or is physically active. The good news is that most sprained knees heal with rest and at-home treatments.
Don’t ignore symptoms like pain and swelling in your knee — especially if you twisted your knee or something hit it. Visit a healthcare provider to get the injury diagnosed. They’ll help you understand what’s damaged, how long you’ll need to heal and when it’s safe to resume training, practice or playing.
Last reviewed by a Cleveland Clinic medical professional on 09/21/2023.
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