(WNDU) - Bone cysts are fluid-filled areas inside of a growing bone that has yet to develop into an actual bone. They are benign, which means not cancerous, and develop in children and young adults ...

Medically reviewed by Lauren Schlanger, MD Key Takeaways A ganglion cyst is the most common cause of a lump on your hand or wrist and often feels round or oval. A carpal boss is a hard, bone-like lump ...