A hip cyst is a fluid-filled space that forms inside a joint that extends from one of the bones that forms the joint of the hip. Hip bone cyst is a benign bone tumor. It does not spread to other parts of the body. It can cause weakening and thinning of the bone.
A foot cyst or a toe cyst or an ankle cyst is a benign fluid-filled space that forms inside the bone which is attached to the joint capsules of the foot or the toe or the ankle. These cysts do not have a regular shape or size and they are generally mobile in nature.
A bone cyst is a hole filled with fluid that develops in a bone. They can develop at any age, but mostly bone cysts affect children and young adults. Unicameral bone cysts are the most common of all of them. They can develop anywhere in the body, but mostly affect the upper arm or thigh.