When to see the doctor for a Baker’s cyst
Swelling that comes on quickly or doesn’t go away may be a sign of infection. Other signs of infection include fever, tiredness, and severe knee pain. You should also call your doctor if you experience shortness of breath along with swelling in your leg.
Pain and/or swelling behind the knee might also be a sign of a blood clot, which is a much more dangerous condition that should be addressed immediately.
Diagnosing a Baker's cyst
Your doctor will perform a physical exam and ask about the symptoms you’re experiencing, which will most likely be related to an injury that occurred to your knee. Because just one knee is affected most of the time, your doctor will compare the affected knee with the other one to assess swelling.
Your doctor can also shine a light on the cyst to see if the fluid appears to light up, as it is translucent under the skin.
While X-rays will not show the presence of a cyst, they will show evidence of the damage that caused your cyst. Your doctor may request an MRI (magnetic resonance imaging) scan to see the cyst itself as well as look for any tearing that may have caused the cyst.
Treatments for a Baker's cyst
A Baker's cyst usually resolves by itself. If your cyst does not go away on its own, or if it is causing you pain, your doctor can drain the fluid with a needle (a procedure known as arthrocentesis).
Other treatments for Baker’s cysts include:
- Over-the-counter (OTC) medications
- Steroid injections in the knee joint
- Surgery that removes the cyst
If an injury or other medical condition like arthritis is causing your Baker's cyst, that problem will need treatment. Otherwise, your cyst may continue to return, potentially causing more damage.
There are steps you can take at home to help your cyst heal. These include:
- Applying a compression wrap or a cold pack
- Using a cane or crutch to reduce pressure on your joint while walking
- Propping up your knee and resting it as much as you can
- Taking OTC anti-inflammatory medications such as ibuprofen
Physical therapy can help if the cyst affects your range of motion or you have permanent damage from an injury. When you have an injury, you may overcompensate by walking or carrying yourself differently. A physical therapist can help you stretch and relearn how to use your knee as the cyst heals.
If your injury is bad enough, your doctor may refer you for surgery to repair the damage. By fixing the problem that caused your cyst, future damage can be prevented.