Bursae are fluid-filled cavities located at tissue sites where tendons or muscles pass over bony prominences near joints, such as the knee. The function of a bursa is to facilitate movement and reduce friction between moving parts.
Linda J. Vorvick, MD, Medical Director and Director of Didactic Curriculum, MEDEX Northwest Division of Physician Assistant Studies, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.