Video Description
A soft swelling behind the knee that moves slightly and sits just below the joint is often a Baker’s cyst — a fluid-filled pocket, also called a popliteal cyst. It can appear with gym or sports activity, or with age-related changes in the knee.
It matters because it usually points to something else happening inside the knee.
This page covers what a Baker’s cyst is, why it forms, and how physiotherapy is typically approached.
Symptoms
- Pain and swelling around the knee
- Difficulty and stiffness bending the knee, felt behind the joint
- Restricted movement past a certain point of bend
- Stiffness behind the knee when standing up from sitting or going down stairs
A small cyst may cause little pain and reasonable mobility. A larger cyst can noticeably affect walking and bending.
Why it forms
A Baker’s cyst usually develops when there is another problem in the knee that increases fluid production, including:
- A cartilage tear from injury, an accident, or ageing
- A meniscus injury to the knee’s shock-absorbing tissue
- Osteoarthritis (joint wear)
How physiotherapy helps
On assessment, a physiotherapist can often identify a Baker’s cyst; an MRI can confirm it and show the number and size of cysts and any underlying damage. For a smaller cyst, treatment first aims to stop fluid accumulating and to help any injured structure in the knee heal, followed by exercises.
As the knee is strengthened, the cyst often reduces gradually as the body reabsorbs the fluid. While it is present, it helps to limit deep bending, repeated stair climbing, and squatting; standing and walking are usually fine. Recovery varies with the underlying cause.
Booking an assessment
If you have noticed a swelling behind your knee, an assessment can check what is driving it. Learn more about knee pain physiotherapy or call to book.
Chennai Physio Care® — Anna Nagar West, Chennai
📞 73052 74514
🕐 Monday – Saturday, 8:30 AM – 7:00 PM
Home visits are available across Anna Nagar, Kilpauk, Mogappair, Arumbakkam, Koyambedu, and Korattur. Call us to discuss whether a home visit is appropriate for your situation.
Last reviewed by Dr. N Vanathy, PT — July 2026 Chennai Physio Care®, Anna Nagar West, Chennai