What is a baker’s cyst?
A baker’s cyst is a pocket of fluid that forms a lump behind the knee. It is also known as popliteal cyst.
What causes a Baker’s cyst?
Baker’s cysts in children often involve the bursa, the small sac of fluid behind the knee. The bursa may join the sac that cushions the knee bones (synovial sac) to form a cyst.
Arthritis is the most common cause in adults, but a Baker’s cyst also can be caused by a knee injury. Swelling from arthritis or knee injury can cause fluid to build up in your knee. The cyst forms when the fluid is push out at the back of the knee.
What are the symptoms of a Baker’s cyst?
Baker’s cyst causes no symptoms for majority of the people. However, some patient may feel:
- Tightness or stiffness behind the knee.
- Swelling felt behind the knee and it gets worse when you stand.
- Slight pain felt behind the knee and pain can radiate to upper calf area. You will fell this when you bend you knee or straighten your knee all the way.
Sometimes the pocket of fluid behind the knee can tear open and drain into the tissues of the lower leg. This can cause swelling and redness in that part of the leg.
How is a Baker’s cyst diagnosed?
Your doctor will physically examine your knee and order investigations such as MRI scan to diagnose the inside of your knee.