Why is my knee swollen?

Following knee replacement surgery, many patients are concerned or surprised by the amount of swelling or even warmth noted about their knee. This occurs almost uniformly after a knee replacement surgery. There’s swelling as the body tries to build scar tissue around the knee. In fact, the physical therapy starts so quickly as to minimize the body’s ability to stop that range of motion. That scar tissue begins to build almost immediately. There’s almost a foreign body reaction as this new implant was recently put in your knee. That warmth can become concerning as certainly there is worry for infection, but the warmth is often without redness. It’s often without drainage from your wound.

If there’s concern you can always call us but know warmth in the knee and swelling usually lasts up to six months after knee replacement surgery. That tight feeling around your knee that round look to your knee again continues until about six months after surgery. You’ll even notice a drastic temperature difference up to six months after surgery. This doesn’t mean there’s an infection; it means that you’re having normal healing and you’re working hard to make that knee better.


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