What Is a Subchondral Bone Cyst? It's a fluid-filled sac that forms in one or both of the bones that make up a joint. They're especially common at the knee or hip. The cysts show up just under the ...

Sarcoma is a type of cancer that originates in the bones or soft tissue. Soft tissue sarcoma (STS) most often begins in the arms and legs but can also occur in other body parts. Soft tissues include ...