Baker’s Cyst Causes, Symptoms & Treatment Options
A Baker’s cyst, also known as a popliteal cyst, is a fluid-filled swelling that develops at the back of the knee. It forms when excess joint fluid builds up and collects behind the knee, often due to an underlying knee condition. While many baker’s cyst knee cases are painless, others can cause stiffness, swelling, and discomfort that worsens with activity.
Start with our quick Symptom Assessment or connect directly with an Upswing Coach today.
Request an AppointmentReady to take the next step?
Start your symptom assessment or connect with a coach instantly.
Find Relief TodayOverview
A Baker’s cyst is a fluid-filled sac that develops behind the knee, often causing a visible bulge or a feeling of tightness, particularly when the knee is fully straightened.The knee naturally contains synovial fluid, which lubricates and cushions the joint, reducing friction between bones, ligaments, and muscles.
When the knee produces too much synovial fluid—usually because of inflammation or injury—the fluid can be pushed into the space behind the knee, forming a cyst. In some cases, a Baker’s cyst can rupture, allowing fluid to leak into the calf and causing sudden pain and swelling.
What causes Baker’s Cyst?
A Baker’s cyst develops when swelling inside the knee joint forces excess synovial fluid into the back of the knee. As this fluid accumulates, it forms a visible and sometimes painful lump.
1. How the Condition Develops
- Increased fluid production inside the knee due to inflammation
- Pressure within the knee joint is pushing fluid backward
- Gradual formation of a cyst behind the knee
2. Common Everyday Causes
- Repetitive knee strain or overuse
- Prolonged standing or walking
- Activities that place repeated stress on the knee joint
Underlying Conditions That May Lead to a Baker’s Cyst
Several knee conditions commonly contribute to bakers cyst formation, including:
- Arthritis (including osteoarthritis): Causes chronic inflammation and excess fluid production
- Knee injuries, such as a meniscus tear: Disrupt normal joint mechanics and increase swelling
- Rheumatologic conditions: Autoimmune or inflammatory diseases that affect joints, tendons, and ligaments
Addressing these underlying problems is key to effective baker’s cyst treatments.
Symptoms
You may have a baker’s cyst if you experience one or more of the following baker’s cyst symptoms:
- Swelling behind the knee and sometimes extending into the calf
- A feeling of tightness or pressure behind the knee
- Difficulty bending, straightening, or fully flexing the knee
- A soft, fluid-filled lump that may change in size over time
- Increased discomfort after physical activity or prolonged standing
Symptoms may fluctuate and can worsen as the cyst enlarges.
When to see a doctor
If symptoms of a Baker’s cyst persist, worsen, or interfere with daily activities, you should see an orthopedic specialist. A growing lump behind the knee, increasing pain, or restricted movement should not be ignored.
Your doctor will ask about:
- Previous knee injuries
- History of arthritis or joint disease
- Activity level and symptom progression
Diagnostic Tests May Include:
- X-ray: To assess joint alignment and rule out arthritis or fractures
- Ultrasound: To confirm the presence of a fluid-filled cyst
- MRI (in some cases): To identify the underlying cause, such as a meniscus tear
Imaging helps confirm the diagnosis and guides appropriate baker’s cyst treatments.
If a Baker’s cyst ruptures, it can cause sudden calf swelling and pain. Because this can mimic a blood clot, immediate medical evaluation is necessary.
Non-operative treatment
Most baker’s cyst cases are treated by managing the underlying knee condition rather than the cyst itself. In many people, the cyst resolves once knee inflammation is controlled.
Common Non-Surgical Baker’s Cyst Treatments Include:
- Resting and limiting activities that strain the knee
- Icing the back of the knee to reduce inflammation
- Non-steroidal anti-inflammatory medications (NSAIDs)
- Ultrasound-guided drainage of excess fluid, if needed
Some Baker’s cysts resolve on their own without direct intervention. However, cysts that continue to grow, cause pain, or limit motion may require further treatment.
Rehabilitation Exercises
Targeted exercises can improve knee strength, mobility, and circulation.
(Refer to the PDF Exercise Program below.)
Surgical Treatment
Surgery for a Baker’s cyst knee condition is rarely required. In most cases, correcting the underlying knee problem causes the cyst to disappear.
Surgical removal may be considered if:
- Conservative baker’s cyst treatments fail
- The cyst is large and painful
- The cyst repeatedly returns despite treatment
Surgery focuses on addressing the root cause rather than simply removing the cyst.
Recovery
Recovery time from a Baker’s cyst varies depending on symptom severity and treatment type.
- Mild cases may resolve within weeks with conservative care
- Cysts that require repeated drainage may take longer to fully resolve
- If surgery is necessary, recovery typically takes at least 4 weeks
Following your doctor’s treatment plan and addressing the underlying knee condition are essential for preventing recurrence.
Dr. Jay Kimmel is a board-certified orthopedic surgeon specializing in sports medicine, arthroscopic surgery, and shoulder and knee disorders. He completed his orthopedic training at New York-Presbyterian/Columbia University Medical Center and a Sports Medicine Fellowship at Temple University.
Dr. Kimmel previously served as the Director of the Connecticut Sports Medicine Institute at Saint Francis Hospital and has held faculty appointments as Clinical Assistant Professor in the Departments of Orthopedics and Family Medicine at the University of Connecticut. He has extensive experience caring for athletes as a team physician for high school and collegiate programs and continues to teach in the athletic training departments at Westfield State University and Springfield College.
Find the Support You Need — Right When You Need It
Whether you’re managing pain for the first time, need ongoing guidance, or require expert medical care, we’re here to help you every step of the way.
ORTHO DIRECT
Video visit with an orthopedic doctor for advice and a care plan.
$30
/MonthMRI DIRECT
Fast, affordable MRI with orthopedic review. No insurance required.
$499
/MonthFrequently Asked Questions
Who commonly experiences a Baker’s cyst?
Baker’s cysts are most common in adults with underlying knee problems such as osteoarthritis, rheumatoid arthritis, or meniscus injuries. Athletes and individuals who place repetitive stress on the knee are also at higher risk. However, a Baker’s cyst can develop in anyone with knee inflammation.
What are the most helpful ways to support healing?
The most effective baker’s cyst treatments focus on reducing knee inflammation and addressing the underlying cause. Rest, activity modification, icing, and anti-inflammatory medications can help relieve symptoms. Physical therapy exercises may improve knee mobility and strength, while fluid drainage may be recommended in persistent cases.
Can a Baker’s cyst go away on its own?
Yes, some Baker’s cysts resolve on their own, especially when knee inflammation decreases or the underlying condition is treated. However, if baker’s cyst symptoms persist, worsen, or limit movement, medical evaluation is important to prevent complications or recurrence.
Is it possible to stay active with a Baker’s cyst?
In many cases, yes. Low-impact activities such as walking, cycling, or swimming are often safe and may help maintain knee mobility. However, activities that cause pain, swelling, or pressure behind the knee should be avoided. A healthcare provider can guide safe activity levels based on the severity of the baker’s cyst knee condition.