Alternate Names : Popliteal cyst
Baker’s cyst is an accumulation of joint fluid (synovial fluid) that forms behind the knee.
Overview, Causes, & Risk Factors
A Baker’s cyst may form by the connection of a normal bursa (a normal lubricating fluid sac) with the knee joint. This type is more common in children.
The condition can also be caused by the herniation of the knee joint capsule out into the back of the knee, which is more common in adults. This commonly occurs with a tear in the meniscal cartilage of the knee.
In older adults, Baker’s cysts are frequently associated with knee arthritis.
Pictures & Images
A baker’s cyst is seen as a swelling behind the knee. It forms when joint fluid collects behind the knee. The swelling may be due from inflammation or from other causes, like arthritis. The condition can be seen in both adults and children.
Review Date : 7/10/2009
Reviewed By : Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; and C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Dept. of Orthopaedic Surgery. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.