Non-Ossifying Fibroma

Also known as: nonossifying fibroma, NOF, fibrous cortical defects, cortical Desmond's.

What is non-ossifying fibroma?

A Non-ossifying fibroma (NOF) is a common, benign (non-malignant / non-spreading) fibrous tissue (like a scar) tumor in boys and girls that is usually found in the thigh (femur) or shin (tibia) bones, but it can occur in other bones.

What causes non-ossifying fibroma? 

The cause is unknown.

What are the symptoms of non-ossifying fibroma?

In most cases, NOF doesn’t cause any symptoms, and is frequently discovered by chance when an X-ray is done. Mild pain and swelling may be present in the affected area. If large it may weaken the bone and increase the risk of a fracture occurring.

What are non-ossifying fibroma care options? 

In most cases, NOFs do not require treatment.

Surgery may be considered if it may weaken the bone, the bone requires stabilization or after a fracture. Many treatment options are available and our Orthopedic and other specialists at Nicklaus Children's Hospital will discuss them with you to ensure the best possible outcome.

Reviewed by: Jack Wolfsdorf, MD, FAAP

This page was last updated on: September 09, 2025 10:23 AM