What is a Baker's Cyst?
A Baker's cyst is also known as a popliteal cyst. It is a benign cyst that is located behind your knee. It is filled with fluid and can cause tightness behind your knee that gets worse when you fully flex or extend your knee. Baker's cyst is named after William Baker (1838–1896), the surgeon who first described it.
What causes a Baker's cyst?
Baker's cyst usually arises from problems with your knee joint. Arthritis or any cartilage tear including a meniscal tear will produce an excess of synovial fluid that will accumulate and cause a Baker's cyst.
Symptoms of a Baker's cyst
Often times there are no symptoms. You could feel knee pain, stiffness, and swelling behind your knee. As well as an inability to fully flex your knee. Symptom's usually worsen after a long period of activity.
Do I need to see a doctor?
You should consult your doctor if you have pain and swelling behind your knee. Although a Baker's cyst is a relatively benign condition, your doctor will want to rule out any serious conditions that can present like a Baker's cyst. Some of these conditions include a tumor, popliteal artery aneurysm, DVT or blood clot.
What do I need to be on the look out for?
Baker's cysts can lead to complications if the cyst bursts and synovial fluid leaks into your calf, which would result in swelling, redness, and pain in your calf. These symptoms are very similar to that of a deep vein thrombosis (DVT) and it is essential to have your doctor differentiate which condition it is. DVTs are a more serious problem that requires immediate medical attention, whereas Baker's cyst is benign and has a great prognosis.
How do I treat it?
A lot of times the Baker's cyst will disappear on it's own and no treatment is necessary. If the cyst causes pain then your doctor could inject the area with a corticosteroid to lower the inflammation and relieve the pain. Your doctor could also drain the fluid from the knee if warranted. The main treatment however, is to treat the underlying cause of the cyst.
Dr. David Carfagno is a Board Certified Internist and Sports Physician, who trained at the Cleveland Clinic Foundation
Huddleston JI, Goodman SB. Hip and knee pain. In: Firestein GS, Budd RC, Harris ED Jr, et al, eds.Kelley's Textbook of Rheumatology.
Biundo JJ. Bursitis, tendinitis, and other periarticular disorders and sports medicine. In: Goldman L, Schafer AI, eds.Goldman's Cecil Medicine