Common Causes of Swollen Knees
There are many reasons that your knee may be swollen. Here are some of the most common.
Recent Injury - Trauma to the joint may cause knee swelling. Just like any other part of the body, when the structure of the knee is damaged it starts to bleed. This causes the knee to swell up and is often accompanied by soreness and bruising.
ACL tear, meniscus tear, or other ligament sprains - One of the most common causes of knee bleeding is a tear or sprain in the ligaments of the knee. When a person ruptures a ligament, it causes the knee joint to bleed. The accumulated blood causes a swollen knee.
Osteoarthritis of the Knee - Also often called "water on the knee", arthritis is the term for the wear and tear on the cartilage and bones in the knee joint. Arthritis often causes the body to produce extra joint fluid in the affected area, so an arthritic knee may experience gradual knee swelling. This is often exacerbated by activity.
Gout - Gout is a form of arthritis, and may affect any joint. One of the most common symptoms of gout is a swollen knee, if that's the joint currently affected.
Knee Bursitis - The area around the knee is cushioned by fluid-filled sacs called bursa. When this area becomes inflamed (usually due to overuse or other repetitive stress injury), it is known as bursitis. As with most inflammations, knee bursitis may cause swelling around the knee.
Infection - Infection in the knee may be caused by a wound or from surgery in the area. A knee joint infection may also be caused by infection from other areas of the body. When the joint is infected, it may cause a swollen knee.
There are other less common causes of swollen knees, such as tumors or knee dislocations, but these are much rarer than the causes listed above.
Diagnosing a Swollen Knee
Your doctor may order an MRI or other type of radiological assessment. A sample of the fluid or blood in the swollen knee may be taken, then sent off for blood tests and further analysis.
Swollen Knee Treatment
The swollen knee treatment varies depending on the cause of the swollen knee. Once the proper diagnosis is made, your doctor will determine the best form of treatment. Here are some common forms of swollen knee treatment:
RICE - As with many injuries, the RICE method (rest, ice, compression, and elevation) may be employed to help treat a swollen knee. Check out our knee sleeves, which may help with compression, and also our knee cold therapy products to help with icing.
Aspiration or Draining - Your doctor may drain the fluid or blood away from the knee in order to alleviate pressure from the area. While this alleviates the swollen knee, further treatment may be necessary for the root cause of the problem (ie. ACL reconstruction for an ACL tear)
Anti-Inflammatory Medication - Over the counter medicines such as ibuprofen or aspirin may help reduce inflammation in swollen knees.
Steroid Injections - A cortisone injection may be used to reduce pain and swelling in the knee. This is typically used for patients with persistent arthritis, though your doctor may suggest for other knee indications depending on the circumstances of the swollen knee.
Surgery - Knee surgery may be necessary to fix a tear or to clean out infection. Surgery itself may cause swollen knees, but usually clears up with time. Again, your doctor may use the RICE method to help relieve swelling after knee surgery.