There are many possible causes for knee swelling. This swelling does not always cause pain, but it should not be ignored. Another term for knee swelling is knee effusion, which is the medical term for water on the knee. The swelling could be from fluid accumulation around the knee. The knee effusion can be severe due to constant stress on the knee from sports or work that places weight on the knee.
Causes of knee swelling could be:
- Bursitis - The result of overfilled sacs called bursa. Bursa is usually extra protection and adds flexibility to the joint. When a bursa in the knee becomes inflamed, it can feel squishy and may not be painful.
○ Prepatellar Bursitis - Is an inflammation of the bursa in front of the kneecap. This condition can be caused by repeatedly kneeling for an extended period.
○ Septic Bursitis - An infection in the knee. This type can have symptoms similar to the flu. Knee swelling and pain can be a late sign of this progressive condition.
- Tumor - Although a tumor can cause the knee to swell, there may not be a pain. One sign is pain only at night.
- Juvenile Rheumatoid Arthritis - Can cause aching and swelling in the knee before age 16. It can also present as an aching in the muscles.
- Osgood-Schlatter Disease - This condition is caused by growth spurts in teens and is mainly found in the area where the tendon from the kneecap connects to the shinbone. Swelling could be found in the tibial tubercle, which is where the tendon that goes across the knee attaches to the tibia.