Water on the Knee (Knee Effusion)

Knee effusion, commonly referred to as "water on the knee," is a condition characterized by an abnormal accumulation of fluid within the knee joint. This excess fluid can cause swelling, pain, and stiffness in the affected knee.

Causes

• Trauma or Injury: Direct blows to the knee, fractures, or ligament sprains can lead to knee effusion.
• Arthritis: Conditions like osteoarthritis, rheumatoid arthritis, and gout can cause inflammation and fluid buildup in the knee joint.
• Infection: Bacterial or viral infections, such as septic arthritis, can lead to knee effusion.
• Overuse or Repetitive Strain: Activities that involve repetitive knee movements, like running or cycling, can cause irritation and fluid accumulation in the knee joint.
• Cysts or Tumors: Benign growths, such as Baker's cysts, or malignant tumors can cause fluid buildup in the knee.

Symptoms

• Swelling: Visible swelling around the knee joint, which may be warm to the touch.
• Pain: Pain or tenderness in the knee, especially with movement or weight-bearing activities.
• Stiffness: Reduced range of motion or stiffness in the knee joint.
• Instability: Feeling of instability or giving way of the knee.
• Limited Mobility: Difficulty walking, climbing stairs, or performing daily activities due to knee pain and swelling.

Diagnosis

Diagnosing knee effusion typically involves a combination of physical examination, medical history, and imaging tests, such as:

• X-rays: To rule out fractures or other bone-related issues.
• Ultrasound: To visualize the fluid accumulation and guide aspiration (fluid removal) if necessary.
• Magnetic Resonance Imaging (MRI): To evaluate soft tissue injuries, ligament sprains, or meniscal tears.
• Arthrocentesis: A procedure where a needle is inserted into the knee joint to remove fluid for analysis.

Treatment

Treatment for knee effusion depends on the underlying cause and may involve:

• Conservative Management: Rest, ice, compression, elevation (RICE), physical therapy, and pain management with medications.
• Aspiration: Removing excess fluid from the knee joint using a needle.
• Corticosteroid Injections: Injecting anti-inflammatory medications into the knee joint to reduce swelling and pain.
• Surgery: In some cases, surgical intervention may be necessary to address underlying conditions, such as ligament repairs or meniscectomy (removal of damaged cartilage).