A Baker's cyst is a fluid-filled swelling that develops behind the knee. This causes the knee joint to produce excess joint fluid (synovial fluid).
The fluid then accumulates to form a cystic swelling at the back of the knee.
If present, the cyst itself is generally not the main issue but it indicates that there is another structure in the knee that has been injured, such as a ligament rupture, meniscus injury or arthritis.
If you’re reading this after a recent MRI of your knee, it may also be referred to as a popliteal cyst on the report and it is likely that the scan has detected other issues within the knee.
Baker’s cyst symptoms
This varies between different knee injuries, but a Baker’s cyst will generally give the feeling of swelling or fullness at the back of the knee.
It can restrict the ability to squat or bend the knee because the cyst can get jammed. Fluid from the cyst can also ‘leak’ down the back of the leg which occupies space and gives a tightness and fullness feeling in the calf zone. In more severe cases, there can be visible swelling in the ankle that generally worsens throughout the day.
As Baker’s cysts are a result of another knee injury or condition, the treatment of a Baker's cyst typically focuses on managing the underlying cause.
Therefore identifying the underlying condition contributing to the Baker’s cyst is crucial. Over time the Baker’s cyst symptoms will improve as the range of motion and strength of the knee improve. Here are some common treatment options:
There may be knee pain with certain activities in life, yet there are some things that you just need to get on with despite your knee injury. Here’s a traffic light system to help you decide what activities are okay to do and which you’re better off avoiding:
Ice for Baker's Cyst
Applying an ice pack to the back of the knee can help temporarily reduce pain associated with a Baker’s cyst. Use a towel to protect the skin and apply for 15-20 minutes at a time while sitting with your leg elevated on a couch
Physiotherapy management for Baker's Cyst
In the early stages of physiotherapy, focus is on restoring full knee joint range of movement and activating the quadriceps as it has such an important role in controlling the knee joint and help movement become pain-free again.
Other potential methods for reducing pain include taping and hands-on treatment which can both be useful where pain is quite limiting and affecting basic day to day activities.
As the knee pain improves, appropriate intermediate and advanced exercises are prescribed to continue to build knee strength with considerations made for single leg balance, hip strength, calf strength and pelvic stability.
There may be other factors such as reduced hip and ankle flexibility which may also need to be addressed to help effectively overcome the knee injury and Baker’s cyst symptoms.
For people who have athletic goals such as sport, gym and running, rehab considerations will be made to help prepare for the needs of those activities which can include impact (jumping and landing) and multi-directional movements.
These are recommended only in some cases. Corticosteroids into the knee joint help to reduce inflammation and relieve symptoms, but on their own do not fix knee injuries as they do not replace a thorough exercise program
Removing the cyst (aspiration)
If the Baker's cyst is particularly large and causing significant discomfort, a healthcare provider may consider draining the excess fluid from the cyst using a needle
In rare cases, the above measures may not be enough and the cyst can persist and cause significant problems. In such cases an opinion from a knee surgeon can be useful for whether surgery could be an option. This should be considered a final option only
For every 1kg of body weight, the knees must absorb 4 times more pressure during walking. That means if you lose 3kgs, that’s 12kg less pressure that your knee must absorb every single time you take a step with that leg.
If multiplied across a full day, it’s a huge reduction of stress that the knee has if you lose weight - so every little bit helps. As the knee pain settles, there will be naturally more options for exercise.
Consulting a Dietician is strongly recommended to help adjust diet if pain is limiting daily life to help prevent unwanted weight gain, and help support healthy weight loss as physical activity increases as the knee recovers over time.
WHAT IS THE BEST MEDICATION FOR A Baker’s cyst?
Combined with appropriate advice and management from a Physiotherapist, medication can be useful for reducing pain short term to enable better movement.
However, oral medication cannot reduce the size of the cyst, and also does not fix the underlying injury which caused the cyst.
Consulting a General Practitioner and/or Pharmacist is recommended if medication is considered to help with pain relief.