What Is a Bone Cyst?
Bone cysts are abnormal, liquid-filled pockets that form within your bones.
They mostly develop in long bones — such as the bones in the arms or legs — and often near a growth plate.
Types of bone cysts
There are two main types of bone cysts:
Unicameral bone cysts
A unicameral — or simple — cyst is the most common type of bone cyst. These cysts are benign, meaning that they are not cancerous and will not spread to other parts of the body.
Unicameral bone cysts occur more often in children and teens than in adults.
Aneurysmal bone cysts
Aneurysmal bone cysts also are benign, but they can be more serious than a unicameral cyst.
Bleeding inside the bone causes aneurysmal bone cysts. If the bleeding continues, it can lead to a large cyst that may deform the bone.
Bone cyst causes and risk factors
There are no known bone cyst risk factors since the medical community does not yet fully understand what causes them.