Fluid accumulation in the knee, often called “water on the knee,” is a common condition that can cause discomfort and limit movement. Medically known as knee effusion, it occurs when excess fluid builds up within or around the knee joint. This article clarifies what knee effusion entails and whether urgent care facilities can provide effective treatment.
Understanding Fluid in the Knee
Knee effusion signifies an abnormal increase in fluid inside the knee joint capsule. An excess can lead to noticeable symptoms. Individuals experiencing knee effusion often report swelling, pain, and stiffness. This fluid buildup can also restrict the ability to fully bend or straighten the knee, impacting mobility.
Various factors can contribute to knee effusion. Common causes include acute injuries such as ligament tears or meniscus damage. Overuse or repetitive strain from physical activities can also trigger inflammation and fluid accumulation. Different forms of arthritis, including osteoarthritis, rheumatoid arthritis, and gout, are frequent culprits. Infections within the joint, known as septic arthritis, represent a more serious cause.
When Urgent Care Can Help
Urgent care centers can address knee effusion, particularly in acute, non-life-threatening situations. They perform knee fluid aspiration, or arthrocentesis, which draws out excess fluid. This procedure provides symptomatic relief by reducing pressure and aids in diagnosing the underlying cause. Urgent care is suitable when symptoms like significant swelling, pain, or difficulty walking arise suddenly, but without signs of a severe, immediately threatening condition.
However, certain situations warrant an emergency room or specialist visit. If knee swelling accompanies a high fever, extreme redness, intense pain, inability to bear weight, or deformity, it could indicate a severe infection (septic arthritis), fracture, or other serious injury. Septic arthritis requires immediate hospital treatment. For chronic or recurring knee effusion, or complex underlying conditions, follow-up with an orthopedic surgeon or rheumatologist is recommended.
The Knee Fluid Aspiration Procedure
Knee fluid aspiration is a straightforward medical procedure to remove excess fluid from the joint. The healthcare provider cleans the skin around the knee with an antiseptic solution. A local anesthetic is then applied to numb the skin and deeper tissues.
Once the area is numbed, a sterile needle is carefully inserted into the joint space. The excess fluid is withdrawn into a syringe. It may be sent to a laboratory for analysis to identify the cause of the effusion, such as infection, inflammatory markers, or crystals. After aspiration, the needle is removed, and a small bandage is applied to the injection site.
After the Procedure and What Comes Next
After knee fluid aspiration, patients may experience mild soreness at the needle insertion site for a day or two. Applying ice packs, resting the knee, and keeping it elevated can help reduce swelling and discomfort. While some normal activities can be resumed, strenuous activities or heavy lifting should be avoided for a couple of days.
Draining the fluid provides symptomatic relief and can alleviate pain and pressure, but it does not address the root cause of the effusion. Follow-up care is important for diagnosis and long-term management. Patients should schedule an appointment with their primary care physician or a specialist to determine and treat the underlying condition to prevent recurrence. Seek prompt medical attention for warning signs like increasing pain, swelling, redness, warmth around the aspiration site, fever, or any discharge, as these could indicate a complication.