Swollen Knee (Water On The Knee)

Sports Medicine and Physical Therapy Clinic In Brookyn, NY Helping Treat Swollen Knee (Knee Effusion) And Other Musculoskeletal Conditions

Knee swelling is sometimes referred to as “water on the knee.” The medical term for this condition is knee effusion. Water on the knee can result from an injury, chronic overuse, or disease. Swelling in a knee joint may limit knee flexibility and function. A person may find it difficult to fully bend or completely straighten a swollen knee, and the joint may naturally bend 15 to 25 degrees while the leg is at rest. At Precision Care Medical & Sports Performance our medical providers will help you diagnose and treat this condition.

What Causes Swollen Knee (Water On The Knee)?

The knee has a joint capsule, which is like a sac that surrounds the whole joint. The capsule contains synovial fluid which nourishes and lubricates the joint, so that it can move smoothly (a bit like the oil in your car). The joint capsule acts as container, keeping the fluid within the knee joint. A swollen knee usually develops when excess fluid builds up inside the capsule and is caused by either: A) Bleeding in the Joint: aka Haemarthrosis. This is normally caused by an injury and the knee swelling comes on rapidly (within minutes). The swelling can be intense making the knee feel very tight B) An accumulation of Synovial Fluid: aka knee joint effusion or water on the knee. This type of swollen knee tends to come on gradually and may come and go, varying in degrees of severity. 

4 Ways Knee Swelling (Knee Effusion) Develops

1) Rapid swelling- that comes on immediately after an injury A swollen knee that develops immediately after an injury, within minutes, is usually due to haemarthrosis, where blood accumulates in the joint. Essentially what happens is that a structure inside the knee gets damaged and starts to bleed, building up pressure in the joint. The swelling is normally profuse and the knee balloons up. It will feel tense and very sore and is often accompanied by bruising, although that may take longer to develop. There are three main causes of a swollen knee from a haemarthrosis: 1) Ligament Tear: Where a ligament ruptures (tears completely). This is the most common cause and usually involves the ACL (Anterior Cruciate Ligament) Tear. Other symptoms include instability and pain 2) Meniscus Tear: A tear in the outer rim of the cartilage lining the knee. Associated symptoms include locking (where the knee gets stuck) and pain on stairs and when squatting 3) Bone Fracture: A break in one of the knee bones such as a patellar fracture. In most cases, it will be obvious if you have broken a bone A swollen knee like this needs urgent medical attention. 2) Delayed swelling- that appears a few hours after an injury If a swollen knee develops anything from a few hours to a few days after an injury, it is most likely due to an increase in the synovial fluid in the joint – a knee effusion. This happens when something inside the knee is damaged slightly causing irritation and a resultant increase in synovial fluid. The amount of swelling varies but it tends not to be as much as with a haemarthrosis and the swollen knee doesn’t usually feel tense. The most common causes of a knee joint effusion are: 1) Meniscus Tear: A tear in the outer part of the cartilage lining the joint (the inner part of the meniscus has a poor blood supply so doesn’t tend to bleed much when damaged) 2) Knee Sprain: Where one of the knee ligaments is overstretched, damaging a few fibres, but the ligament remains intact The amount of knee swelling may vary day to day and it may feel like it comes and goes as the injury is healing. It usually takes 6-12 weeks for soft tissues (i.e. muscles & ligaments) to heal, but cartilage injuries can take longer, as the cartilage has a very poor blood supply (PRP Injection For Meniscus Tear) 3) Gradual swelling -that develops and often fluctuates without an injury A swollen knee that develops gradually is usual a sign of an underlying knee condition rather than an injury. The fluid on the knee tends to come and go and varies in amount. There is usually only mild to moderate amounts of swelling. 4) Rapid swelling- that comes on very suddenly without an injury Occasionally, a swollen knee develops rapidly without any injury. The most common causes of this are: 1) Infection: Infections increase in the amount of fluid produced in the joint resulting in a swollen knee. They usually develop after surgery or a deep cut, but sometimes an infection in your body can spread to your joint. It is very difficult for your body to fight an infection within a joint and sometimes surgery is required 2) Gout: High levels of uric acid (produced as part of the digestive process) cause sharp, needle like crystals to form in your joints leading to inflammation and water on the knee. It is usually treated with medication and appropriate diet.

7 Ways To Reduce Swelling In The Knee

Treatment will depend on the cause of the swollen knee, but the most common ways to reduce the swelling are: 1) Ice: can be used to slow down the blood flow and therefore reduce swelling and pain. It is important to use it properly otherwise it can make things worse – see theIce Therapy section for more details and the ice wraps section for the best ways to apply ice 2) Compression: Knee braces can be used to provide compression to the knee which helps reduce swelling 3) Medication: Non-steroidal anti-inflammatories (ibuprofen) may be prescribed to reduce the knee swelling 4) Aspiration: A swollen knee can be drained by a knee pain specialist with a needle, but it does sometimes come back 5) Cortisone Injections: Cortisone is a steroid hormone that suppresses the immune system, reducing inflammation and pain 6) Elevation: Keeping the leg elevated, ideally with the knee higher than the level of the heart can help treat a swollen knee as gravity draws the fluid down away from the knee 7) Rest: Reducing your activity levels helps to take pressure of the knee which can reduce swelling otherwise the knee keeps getting irritated

How Precision Care Medical & Sports Performance can help you treat a swelling in the knee?

Our team of medical providers consisting of Sports Medicine Doctor NYC and Sports Physical Therapy at Precision Care Medical & Sports Performance focus is on finding the best non-operative treatment solutions to resolve patients’ pain and injuries. If you’d like to learn more about our services, we invite you to contact us to schedule an appointment. We participate with most health insurance plans including Medicare, Medicaid, No-Fault(Car Accidents), Workers Compensation(work related injuries). We offer same or next day appointments and Complimentary Injury Screens. Call us today (718)648-1234 

Physical Therapy Near Me