Nonossifying Fibroma – Bone Tumour – Easy MBBS

Nonossifying Fibroma – Bone Tumour

• Developmental defect (A nest of fibrous tissue appears within the bone and persists for some years before ossifying)
• Asymptomatic (an incidental finding on x-ray)
• Metaphysis of long bone
• Multiple lesions (vast majority arises eccentrically in the metaphysis of the distal femur and proximal tibia and almost half are bilateral or multiple)

Commonest sites of Nonossifying Fibroma

• Metaphysis of long bone
• Multiple lesions (vast majority arises eccentrically in the metaphysis of the distal femur and proximal tibia and almost half are bilateral or multiple)

• Although asymptomatic nonossifying fibroma is an active lesion that persist and enlarges throughout childhood.
• Pathological fracture can occur, when the tumour occupies more than 50% of the diameter of the bone.
• With skeletal maturation non-ossifying fibromas becomes inactive or latent and ultimately ossify.

Pathology of Nonossifying Fibroma

• It looks cystic on X-Ray, though it is a solid lesion
• It consist of unremarkable fibrous tissue with a few scattered giant cell
• Macroscopically composed of soft reddish tan, granulation like tissue.
• Dense collagen arranged in a storiform pattern.

X-Ray of Nonossifying Fibroma

• Appearance is unmistakable
• A more or less oval radiolucent area surrounded by a thin margin of dense bone.
• It is actually adjacent to or within the cortex; hence the alternative name is fibrous cortical defect.

Treatment of Non-ossifying Fibroma

Treatment is unnecessary

Treatment can be done only

1) When diagnosis is in question

2) Pathological fracture is significant risk

Intracapsular curettage supplemented with bone graft or other stabilizing technique can be done.