Water on the knee or knee effusion is a condition characterized by the accumulation of excess fluid in the knee joint. This condition causes knee swelling or inflammation. Find out the factors that can cause knee effusion, as well as the treatment options available for this condition, through this Buzzle article.

Exercises that strengthen the thigh muscles can help prevent knee problems, as strong thigh muscles can provide better support to the knee joint.Water on the knee refers to an accumulation of fluid in or around the knee joint, which results in swelling and inflammation. The medical term for this condition is knee effusion. The lining of the knee joint capsule usually produces a lubricating fluid, known as synovial fluid. This fluid facilitates the movement of the knee joint and nourishes the cartilage.

But some factors like injuries, infections, or certain diseases can cause an overproduction of synovial fluid. After an injury or trauma to the knee joint, the body tries to surround the joint with protective fluid, which results in knee effusion.

Causes of Knee Effusion
✧ Sometimes, the synovial fluid can accumulate in the knee joint due to a physical injury or trauma. An injury caused by the overuse of the knee joint, fracture, cartilage tear, or meniscus tear can damage the tissues and capillaries of the knee, leading to the leakage and buildup of tissue fluid.

✧ Arthritis can also be associated with knee swelling and fluid buildup. Osteoarthritis is a degenerative disease that can cause chronic breakdown of the cartilage of the joints. It has been found to be one of the most important causes of knee effusion. On the other hand, rheumatoid arthritis is an autoimmune disease, which can also cause the accumulation of fluid in the knee joint.

✧ Many times, it has been observed that bacteria can spread to the joints from the bloodstream, and cause a disease known as bacterial arthritis. This condition can also cause knee effusion. People with diabetes and rheumatoid arthritis are more prone to develop bacterial arthritis.

✧ Gout is another disease associated with knee effusion, where uric acid crystals accumulate in the knee joint due to a defect in uric acid metabolism. Apart from these, pseudogout, cysts, tumors, and kneecap bursitis are some other causes of knee effusion.
Knee Effusion Symptoms
✧ Pain, stiffness, and swelling are the most common symptoms of this condition. The pain caused by this condition has been observed to subside with rest.

✧ Along with swelling, one can feel puffiness around the bony parts of the knee. An accumulation of fluid in the knee joint can limit the movement of the affected individual. The affected individual may experience stiffness or difficulty in bending or straightening his or her knee.

✧ If fluid accumulation is caused by an injury, then bruising can be easily noticed. In such a situation, the affected individual may find it impossible to bear weight on the injured knee.
Diagnosis and Treatment
Diagnosis

As knee effusion can be caused by several factors, it is quite important to determine the underlying cause(s) to ensure its proper treatment and speedy recovery. Several tests are carried out to diagnose the underlying causes of knee effusion, which are explained below.

X-ray: An X-ray is done to look for fractures, or broken and dislocated bones.

Magnetic Resonance Imaging (MRI): MRI is usually conducted when X-rays fail to detect the underlying cause of the swelling. It basically helps identify tendon and ligament injuries not visible in an X-ray.

Ultrasound: Ultrasound is employed for evaluating joint pain and swelling. It helps diagnose arthritis, as well as disorders of the tendons and ligaments.

Blood Tests: Blood tests are usually carried out to detect the presence of an infection, bleeding disorder, and Lyme disease. It can help diagnose conditions like rheumatoid arthritis and gout as well.

Joint Aspiration: It is also known as arthrocentesis, wherein a sample of the fluid accumulated in or around the knee joint is withdrawn, and then examined to detect the presence of blood, bacteria, and crystals.

Arthroscopy: Arthroscopy is performed to examine the inside of the knee joint. This procedure involves the insertion of a small, lighted tube with an arthroscope (a type of magnifying lens) through a small incision made on the knee.
Treatment

Depending on the underlying causes, the treatment of knee effusion can differ significantly. To treat the symptoms, over-the-counter pain medications are usually prescribed by physicians. If they fail to provide relief, then stronger drugs can be prescribed to ease the pain.
As mentioned already, blood tests and a joint aspiration are carried out to detect the presence of an infection. If the presence of an infection is confirmed, then it can be treated with appropriate antibiotics.
Non-steroidal anti-inflammatory drugs (NSAIDs) can also be prescribed to reduce the swelling and stiffness associated with knee effusion. Corticosteroids are another class of drugs that can be used for treating knee effusion, especially if the inflammation is severe and does not respond to NSAIDs. But these medications can produce several side effects, some of which can be quite severe.
If gout and pseudogout are responsible for causing fluid accumulation in the knee joint, your physician can recommend colchicine, along with corticosteroid injections and NSAIDs. Allopurinol or probenecid are the drugs that can help lower the production of uric acid in the body. So, these medications can help prevent gout-related knee effusion.
A large buildup of fluid, along with severe inflammation can require a joint aspiration. So, joint aspiration is not only a diagnostic test, but also a treatment option for knee effusion. As mentioned already, it involves the removal of the fluid accumulated around the knee joint. Physicians can sometimes administer a corticosteroid injection after removing the excess fluid from the knee joint, if the inflammation is severe in nature.
Arthroscopy or Arthroscopic knee surgery is another treatment option, wherein a surgical tool, known as arthroscope is used to examine the knee joint. This instrument can also be used to repair or remove the damaged tissues present in the knee joint.
If all these treatment options fail to provide relief, and if it becomes impossible to stand or bear weight on the knee joint, then knee replacement surgery may be required.
Home Remedies
If you develop knee effusion, you can employ the following home remedies or lifestyle changes to reduce the accompanied pain and swelling.

☑ Give rest to your knee joint to speed up the healing process. Avoid weight-bearing activities as much as possible.

☑ Cold therapy or the application of ice on the affected knee can help reduce the swelling caused by knee effusion. To make it more effective, you can apply an ice pack (a bag of ice/iced towel/frozen vegetables) for about 15 to 20 minutes after every 2 to 4 hours.

☑ Elevation can also relieve the pressure on your knee joint, and return the blood to the upper part of the body. The injured knee should be elevated higher than the level of the heart, by placing some pillows under the leg.

☑ Use crutches or walking devices to protect the knee joint from further injury. Walking devices like crutches help remove the pressure from your knee joint while walking. Knee braces can also be used for protecting the knee.
The main risk factors for knee effusion are osteoarthritis, gout, and obesity. Obese people are likely to experience this problem over a period of time, due to the excess weight or pressure placed on the knee joints while walking or doing other activities. So, if you are obese, then consider to lose weight by exercising, but make sure that you do not injure or overuse the knees while doing so. People having an increased risk of developing knee effusion should remain vigilant against the disease, and report any kind of knee problems immediately to their physicians. As far as the treatment and medications are concerned, follow the advice of your physician and refrain from self-medicating.

Disclaimer: This article is for informative purposes only, and should not be treated as a substitute for professional medical advice.