HEALTH CONDITION

Baker's cyst

A Baker's cyst (popliteal cyst) is a fluid-filled lump at the back of the knee. It may get better on its own or by treating the condition causing it, but you should get any lumps checked by a GP.

Symptoms of a Baker's cyst

The main symptom of a Baker's cyst is a soft lump at the back of the knee. The fluid-filled lump may be more visible when standing up. Credit: Science Photo Library: https://www.sciencephoto.com/media/550738/view The lump may be your only symptom, but you may also have: knee or leg pain tightness, stiffness or aching in your knee difficulty bending your knee clicking in your knee Your symptoms may be worse after walking.

What happens at your appointment

The GP will examine your leg and check for other health conditions that could be causing a Baker's cyst. They may send you for an ultrasound or MRI scan , or refer you to a specialist for more tests or to rule out any serious causes.

Treatment for a Baker's cyst

A Baker's cyst does not always need treatment. Sometimes, particularly in children, it will get better on its own. If the Baker's cyst is caused by an underlying condition, your symptoms will usually get better when that condition is treated. But other treatments for a Baker's cyst can include: painkillers a painkilling injection ( hydrocortisone injection ) in your knee physiotherapy draining fluid out of the cyst surgery to repair damage to your knee joint – it's rare to have surgery to remove a Baker's cyst A Baker's cyst can take a few months to a few years to get better.

Things you can do if you have a Baker's cyst

There are things you can do to ease the pain, swelling and other symptoms of a Baker's cyst while it gets better. They can also help if a Baker's cyst has burst (ruptured). If this happens, your symptoms will be worse than normal until the swelling goes down, which can take a few weeks. Do rest your knee gently apply an ice pack (or a bag of frozen vegetables) wrapped in a tea towel to your knee for around 10 minutes at a time, and repeat every few hours if needed raise your leg – you can rest it on a pillow take ibuprofen or paracetamol to help with pain and swelling

Causes of a Baker's cyst

Sometimes there is no particular cause of a Baker's cyst, especially in children. In adults they usually happen when another health condition causes damage to the knee joint, like: a knee injury osteoarthritis or rheumatoid arthritis gout Anyone can get a Baker's cyst, but they are more common in people aged 35 to 70.

Source: NHS, last reviewed 26 June 2025. Contains public sector information licensed under the Open Government Licence v3.0.

This page is general information and is not medical advice. It does not replace a registered doctor, and it is not a prescription or a recommendation to use any medicine or test. Prices are listed prices and may change. Always follow the advice of your doctor or pharmacist.