Menu

DVT or Baker's Cyst? How to Tell the Difference

Medically Reviewed by Jennifer Robinson, MD on May 09, 2022

DVT and Baker’s cyst show up in your body similarly. In fact, it can be difficult for a doctor to tell which condition you’re dealing with just by looking at your body. But each condition has completely different causes and treatments.

DVT and Baker’s Cysts Basics

DVT happens when a blood clot forms deep in a vein. Veins are blood vessels that carry oxygen-low blood toward your heart after delivering the oxygen to your tissues. Most often, clots can form in the lower part of your body such as your legs, thighs, or pelvis. But you can also get them in your arms.

Blood clots in a vein can slow down or block blood flow. DVTs can trigger serious issues or even death if they break free from their original spot and travel through your bloodstream to your lungs. This blockage is called a pulmonary embolism (PE). PE can damage your lungs or even stop blood from getting to them altogether.

Baker’s cysts, sometimes called popliteal cysts, don’t involve veins or your bloodstream. These cysts happen when synovial (joint) fluid builds up behind your knee. Synovial fluid lubricates your knee joint and helps it move smoothly.

Problems with your knees might lead to Baker’s cysts. These include:

  • A tear in your knee cartilage
  • Cartilage injuries
  • Knee arthritis (in older adults)
  • Rheumatoid arthritis
  • Other knee problems that cause knee swelling

What Symptoms Do DVT and Baker’s Cyst Share?

You might find it hard to tell whether you’re dealing with a Baker’s cyst or DVT because some of their symptoms overlap. Both can cause:

  • Swelling in the leg
  • A spot that’s warm to the touch
  • Bruising or discoloration
  • Tenderness in the swollen area

DVT and Baker’s cysts can both show up as swelling without discomfort, making them both sometimes hard to notice. You might find it harder to bend or move your leg with both.

Sometimes Baker’s cysts can rupture. If this happens, you may feel a sharp pain in your knee, and you’ll see swelling down your calf. Your calf may also look red. These symptoms are similar to DVT in your lower leg.

How Are DVT and Baker’s Cyst Diagnosed?

A Baker’s cyst will only swell behind your knee. But DVTs can happen anywhere in your leg or even your arm. But if your DVT is causing swelling behind the knee, your doctor will look at your body and do certain tests to see which condition you’re dealing with.

They’ll likely try to gather as much info as possible with the following questions:

  • Where is the point of tenderness?
  • Is the swelling in one specific spot or widespread?
  • Has skin color changed?
  • Is there fever?
  • Was there an injury in this spot recently or in the past?

They’ll compare your affected leg with the other one to see the differences. They may also ask you to flex and extend your knee to see if there’s pain with the movement.

To get a fuller picture of what lies beneath the surface of your swollen leg, your doctor may use:

Ultrasound. This imaging test can show your doctor the flow of blood in your veins and whether there are blockages or clots. It can also show your doctor if the lump behind your knee is solid or fluid.

Blood test. A test called the D-dimer blood test can look for a certain substance in your blood that clots release when they break up. A negative D-dimer usually means you do not have a clot.

X-ray. To look for DVT, your doctor can inject dye into the vein they suspect may have a clot and look at images of it. For a Baker’s cyst, X-ray can’t show the cyst itself, but your doctor can look for arthritis in your knee.

MRI. Doctors don’t typically use this imaging test to look for DVT, but it does show your veins and any clots in those veins. It can also give your doctor more information about your knee joint to help them diagnose or rule out Baker’s cyst.

What Are the Treatments?

Treatments for DVT won’t work on Baker’s cysts, and Baker’s cyst treatments won’t help you manage DVT.

Standard DVT treatments include:

Medications. Doctors most commonly treat DVT with medications called blood thinners (anticoagulants). Though they don’t get rid of clots, they do help keep the clots you have from getting bigger. And they stop new clots from forming.

If you can’t take blood thinners, or need more aggressive treatment for DVT, your doctor can try clot busters, or thrombolytics. These medications work to break up existing clots, but come with a higher risk of severe bleeding.

Filters. Your doctor can insert a filter into a large vein called the inferior vena cava to help catch and stop any clots traveling through your bloodstream before they reach your lungs.

Thrombectomy. In some cases, your doctor may decide to do a procedure to physically remove a clot using a small flexible tube.

Common Baker’s cyst treatment includes:

Medication. To reduce swelling in your knee and help with pain, your doctor may give you a shot of corticosteroid.

Fluid drainage. Your doctor can use ultrasound to help guide a needle into your joint to drain extra fluid.

Physical therapy. A physical therapist can teach you special exercises to help reduce symptoms and increase your flexibility and strength.

Your doctor may also need to treat any underlying conditions you have that could be causing the cyst.

Show Sources

SOURCES:

Emergency Medicine News: “Distinguishing Baker's Cyst from DVT.”

CDC: “What is Venous Thromboembolism?”

Penn Medicine: “What is Baker's Cyst (Popliteal Cyst)?”

Mayo Clinic: “Baker’s Cyst”

The Bangkok Medical Journal: “Differentiation between ruptured Baker’s cyst and deep vein thrombosis (DVT).”

Cleveland Clinic: “Baker’s Cyst.”

© 2022 WebMD, LLC. All rights reserved. View privacy policy and trust info