The most common causes of swollen knees are injuries, including broken bones and torn ligaments, according to Mayo Clinic. Injuries damage the knees, leading to accumulation of too much fluid in or around the knee joint. Certain diseases and conditions can also bring about swollen knees.
Other injuries that can lead to knee swelling include cartilage or meniscus tears, and knee overuse, which may lead to irritation, states Mayo Clinic. Conditions that can give rise to swollen knees include bursitis, osteoarthritis, rheumatoid arthritis, tumors and infections. Cysts, gout and pseudogout may as well cause knees to swell.
Risk factors for swollen knees include advanced age and obesity, explains Mayo Clinic. Too much weight puts pressure and stress on the knee joint and tissues surrounding the knee. Sports such as basketball may twist the knee, leading to swollen knees. Knee swelling may result in muscle weakening, muscle degeneration and painful fluid-filled sacs.
Symptoms of swollen knees include pain, swelling of the kneecap and stiffness of the knee, notes Mayo Clinic. Resting the knee, raising the affected leg higher than the heart, applying a cold compression and taking nonprescription pain killers may aid in alleviating symptoms. A patient with a swollen knee should seek medical assistance if symptoms persist or the knee becomes red and sensitive.