osteoid osteoma

An osteoid osteoma is a benign bone tumor. They are small, more often occur in boys, and most often are found in the femur (thigh bone) or tibia (shin bone). They are characteristically painful, in that the pain gets worse over time, is worse at night, and is relieved by aspirin. They may be surgically removed, but some can be treated conservatively with aspirin, since some tumors disappear after skeletal maturity is reached in the late teens.