Signs & Symptoms of a Hyperextended Knee

iknee xray image by JASON WINTER from

Hyperextended knee injuries occur frequently. The knee can easily be stretched or twisted in a way that tears ligaments and causes intense pain, discomfort or long-lasting effects. There are immediate signs that you might have hyperextended your knee, and symptoms that continue days after the injury.

What is Hyperextension?

A hyperextended knee injury occurs when the knee extends past a normal range of motion in the straight position. Essentially, the knee bends back on itself. Hyperextension can range from a mild injury, which is sore but heals in two to four weeks, to a severe injury requiring surgery and extensive knee pain medicines.

Immediate Symptoms

You will experience several symptoms right away if you hyperextend your knee and will recognize the need for knee pain help. You might hear or feel a pop, and it might feel as if your knee has been thrown out of line. You will experience pain at the back and sides of your knee, and swelling within the first few hours of the injury. Most significantly, you will be unable to continue playing, running, etc., on your knee. The knee may become unstable, but instability is not always readily noticed because of the swelling. You might be able to walk on it, but it will be painful.

When to Seek Care for a Hyperextended Knee

If you have been injured enough that your knee is swelling, feels unstable or there is impaired motion or pain, you should seek knee pain treatment and be evaluated by your health care provider as soon as possible. Do not try and diagnose or treat knee injuries on your own. The knee is a complex joint and can have many different injuries. Proper treatment of those injuries is imperative for full recovery.

Time Frame: Recovery from Hyperextended Knee Injury

A mild hyperextension of the knee may require only two to four weeks to heal. Rest and physical therapy will be the primary modes of treatment, and knee pain medicines may be prescribed. A knee that has experienced a ligament tear during the injury may require surgery and will likely require physical therapy and six to nine months of convalescence before returning to athletic activity.


Immediate treatment of a hyperextended knee should include using crutches, elevating it when you are sitting or lying down and icing your injury. Acetaminophen also can reduce pain. Knee pain treatment will depend on the severity of the injury. Rest and physical therapy may be required for a mild hyperextension, while surgery may be an option for a hyperextension that has resulted in a ligament tear.