To determine the cause, a healthcare provider may order imaging tests or performarthrocentesis.
Removing the fluid may also reduce pain and stiffness.
Once the underlying cause is found, treatment can be administered.
This may involve rest, knee immobilization, antibiotics, painkillers, steroid injections, and possibly surgery.
Verywell / Brianna Gilmartin
Swollen Knee Symptoms
Theknee jointis surrounded by a capsule.
Certain conditions can cause this fluid to accumulate.
When this happens, the knee can swell, leading to a knee effusion.
A Baker’s cyst is painless and often feels like a water-filled balloon.
However, if the cyst break opens, there may be pain, swelling, and bruising.
Knee Effusion or Edema?
A swollen knee isn’t always due to effusion.
It can also be because of the buildup of fluids outside of the joint space, callededema.
With knee edema, swelling occurs primarily in the soft tissues of the knee.
Knee edema can also occur independently, most often when the lower legs are affected.
Peripheral edema can cause puffiness, warmth, and a feeling of heaviness, typically without pain.
Both knees are generally affected.
Overuse knee injuries are commonly associated with sports like running or occupations that require heavy lifting or squatting.
Other conditions cause knee inflammation due to knee joint deterioration, causing bone to rub against bone.
These include:
Diagnosis
The first step in treating aneffusionis to pinpoint the cause.
The physical exam can reveal a lot about the underlying cause.
When the swelling is in the overlying soft tissues, the kneecap may hidden beneath the swelling.
RICE Protocol
Knee swelling due to an acute injury or flare-up is typically treated with theRICE protocol.
Medications
Different medications may be prescribed to treat different causes of knee swelling.
It can be diagnosed with a physical exam, imaging studies, and joint aspiration.
Treatment is directed by the findings of the lab and imaging tests.
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