Your knee is a complex joint that has many moving parts. This makes it more prone to injury.

As we age, the stress of everyday movements and activities can be enough to trigger symptoms of pain and fatigue in our knees.

If you’re going about your everyday activities and feel sudden knee pain, it can be hard to know what to do next. Some causes of sudden knee pain are health emergencies requiring attention from a medical professional. Other knee conditions you can treat at home.

In this article, we’ll walk you through conditions that cause sudden knee pain so you can spot the differences and plan your next steps.

Causes of sudden knee pain

Knee pain that appears out of nowhere may seem like it couldn’t be related to an injury. But the knee is a tricky body part. It consists of many parts that can become:

• stretched out

• worn

• aggravated

• partially torn

• fully ruptured

It doesn’t take a traumatic blow or hard fall for the parts of your knee to become injured.

Here’s a summary of common knee issues. More information about each issue (and their treatment options) follows the table.