Although aneurysmal bone cysts can be painful and uncomfortable they are not dangerous and are non cancerous.
Aneurysmal bone cysts are blood filled, fibrous cysts that expand the bone and can cause pain but are not dangerous to your health and you can have them removed through some surgery if you want too.
To remove the cyst the surgeon will perform what's known as Intralesional curettage, which involves scraping out the bone to completely remove the tumor and all cyst lining.
It's a pretty simple procedure and is a good idea to have the cyst removed even though the cyst itself is not dangerous but having the surgery will stop the pain from the cyst.