Kneecap (Prepatellar) Bursitis
What it is
Plumbers, carpet layers, and other people who spend a lot of time on their knees often experience swelling in the front of the knee. The constant friction irritates a small lubricating sac (bursa) located just in front of the kneecap (patella). The bursa enables the kneecap to move smoothly under the skin. If the bursa becomes inflamed, it fills with fluid and causes swelling at the top of the knee. This condition is called kneecap (prepatellar) bursitis.
Who Is at Risk?
This can occur during surgery as the physician retracts soft tissues as part of the procedure. This can also break intercellular bridges and release substances that promote blood clotting.
Other factors that may contribute to the formation of thrombi in the veins include:
Source from AAOS, Viewmedica, WebMD