What is a Baker's Cyst?
A Baker's cyst, also known as a Popliteal cyst, is a type of fluid-filled swelling that occurs behind the knee. These cysts are often painless and cause no symptoms apart from feeling of a swelling in the back of the knee, but they can occasionally become large and uncomfortable, especially if they put pressure on the nerves or blood vessels in the area.
Baker's cysts are typically the result of underlying conditions such as arthritis. The most common type of arthritis that can cause a Baker's cyst is osteoarthritis, which is a degenerative joint disease that affects the cartilage in the knee. Other conditions that can lead to the development of a Baker's cyst include rheumatoid arthritis, gout, and knee injuries such as tears in the meniscus or joint capsule.
How is a Baker's Cyst diagnosed?
Diagnosis is a combination of clinical signs and imaging. Symptoms of a Baker's cyst include swelling, discomfort, occasional pain, a feeling of tightness in the back of the knee, and difficulty bending or straightening the joint. In some cases. If a Baker's cyst is suspected, a doctor will typically perform a physical examination and order imaging tests such as an xray, ultrasound or MRI scan to confirm the diagnosis and exclude other causes of knee swelling. An ultrasound is usually the imaging modality of choice in diagnosing a Baker's cyst and can be performed in clinic. Xrays are very useful in diagnosis Knee osteoarthritis and MRI scans are the gold standard in visualising the meniscus, ligaments and Knee cartilage.
What are the available treatments for Baker's cyst?
Treatment for a Baker's cyst often involves addressing the underlying condition that is causing it, such as managing arthritis with medications or physical therapy.
Although Baker's cysts are generally not serious, they can be uncomfortable and can interfere with a person's ability to move and exercise. It is important to see a doctor if you experience any symptoms of a Baker's cyst, so that the underlying cause can be identified and treated.
Although not commonly performed due to high chance of recurrence, a Baker's cyst can be drained if it is causing significant discomfort or if it is at risk of rupturing. This procedure is typically performed by a doctor, who will use a needle to remove the fluid from the cyst under ultrasound guidance to avoid nerve or blood vessel injury. In some cases, a small incision may be made to drain the cyst, but this is less common. It is preferable to treat the underlying problem in the knee rather than draining the fluid from the cyst.
Can injections help in Baker's Cyst?
Although not considered a treatment of Baker’s cyst per se, Hyaluronic acid injections help with knee pain in patients with osteoarthritis of the knee. Hyaluronic acid is a substance that is naturally present in the body, and it plays a role in lubricating and cushioning the joints. Injections of Hyaluronic acid may help to reduce pain and swelling in the knee, and they may improve joint function. However, these injections are not typically recommended as a first-line treatment for a Baker's cyst.
In summary, If you have a Baker's cyst, the best course of action is to see a doctor for a clinical evaluation, ultrasound scanning and treatment plan. The doctor may recommend medications, physical therapy, or other treatments to manage the underlying condition that is causing the cyst. In some cases, the cyst may need to be drained if it is causing symptoms or if it is at risk of rupturing. The doctor will be able to provide you with more information about the potential benefits and risks of more invasive treatments like injections or surgery.
At ACTIVATE Musculoskeletal Clinic in Kent, patients have access to doctor-led non-surgical treatments for Knee pain including medications, physiotherapy, ultrasound scanning and injections. Book your appointment online or contact us to find out more.
About the Author: Dr. Mustafa Alnaib MBChB, MRCS, MSc, FEBOT is an orthopaedic surgeon, musculoskeletal doctor and Clinic Director at ACTIVATE Musculoskeletal Clinic in Kent.