Accessibility Tools

Knee Effusion

What is Knee Effusion?

Knee effusion also known as water on the knee or swollen knee is a condition characterized by swelling in the knee joint due to the excess accumulation of synovial fluid(the fluid which surrounds the joint)or leakage of lymph fluid or blood into the joint space.

Picture of Knee Effusion

Causes of Knee Effusion

Some of the common causes of knee effusion include:

  • Trauma to the knee
  • Overuse injuries
  • Osteoarthritis
  • Rheumatoid arthritis
  • Gout
  • Septic arthritis
  • Infection
  • Obesity
  • Tumor

Symptoms of Knee Effusion

In addition to a swelling of the joint, knee effusion may be associated with:

  • Warmth
  • Redness
  • Pain
  • Stiffness
  • Difficulty walking

Diagnosis of Knee Effusion

Your doctor will review your medical history and symptoms and based on this a physical examination will be performed. Some of the common diagnostic tests include:

  • Joint aspiration: Also known as arthrocentesis, this procedure involves the removal of fluid from the joint space using a needle and syringe. The fluid is tested in a lab for the presence of infection, bleeding, or gout. Removing fluid from the knee also provides temporary relief of symptoms.
  • Magnetic Resonance Imaging (MRI Scan): This is an imaging study that uses a large magnetic field and radio waves to detect any damage to the soft tissues.
  • X-rays: During this study, images of the bones are produced using high-energy electromagnetic beams.
  • Ultrasonography: This study uses high-frequency sound waves to produce images of the internal parts of the knee.

Treatment for Knee Effusion

Treatment for knee effusion depends on the cause. It can include:

  • RICE Method: This is an acronym that stands for Rest, Ice, Compression, and Elevation. This is the initial treatment suggested for an injured knee.
  • Medications: Your doctor will prescribe medications to reduce swelling and pain. Antibiotics may be prescribed if the infection is present.
  • Steroid injections: Steroid medications may be injected into the knee joint to relieve inflammation.
  • Arthrocentesis: In this technique, fluid is removed from the joint space by inserting a needle to withdraw the fluid. Your doctor may then inject corticosteroids to relieve inflammation.
  • Physical therapy: Exercises may be recommended to improve knee strength and movement.
  • Weight management: Weight reduction is recommended for individuals with obesity as it reduces stress on the knee joints.
If non-conservative methods are found to be ineffective, surgery may be recommended and may include:
  • Knee arthroscopy: This is a minimally invasive procedure in which your doctor will insert an arthroscope(thin illuminated tube with a tiny camera at one end) and other instruments through tiny incisions over the joint in order to surgically repair or reconstruct the tissues and clean out the joint.
  • Knee replacement: Your doctor might suggest replacement of the total knee joint for severe pain and disability.