Q: I have pain in my low back. My doctor says I have a facet synovial cyst. What is this, and what can I do?
A: Synovial cysts are soft, fluid-filled lumps, which can form in joints throughout the body. Facet cysts occur near the facet joints of the spine. The spine is a stack of bones (vertebrae) with cushioning disks in between. The vertebrae have spiky projections on the back, which connect to the projections on the vertebrae above and below via small joints called facet joints. These are synovial joints, meaning they are surrounded by a membrane (synovium), which produces a fluid to provide nourishment and lubrication to the joint.