Why Is One Knee Swollen but Not the Other?

Noticing that only one knee is swollen can be alarming—especially when the other knee feels perfectly fine. While swelling in both knees often points to systemic issues like arthritis, swelling in just one knee usually indicates a localized problem. Understanding the potential causes behind unilateral knee swelling can help you decide whethe
The most common reason for swelling in just one knee is trauma or overuse. You may not even remember the specific moment of injury—especially if it was a repetitive motion injury. Some possible issues include:

Ligament sprain or tear (ACL, MCL)