Simple bone cyst

A bone cyst, or geode, is a cyst that forms in bone. They are benign and can be found in various bones in the body. Bone cysts may or may not contain fluid. Although many types of bone cysts may be associated with trauma, the cause is often unknown. Types include simple bone cysts, aneurysmal bone cysts, traumatic bone cysts, and epidermoid bone cysts.

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