Synonyms

• Non-ossifying fibroma
• fibrocortical defect

Category

Bone

Behaviour

Benign

Gender

Both equally

Tissue of Origin

Fibrous

Epidemiology

• Common Benign Fibrous lesion in children and young adults
• Usually incidental finding
• Predilection for distal femur and proximal tibia

Clinical Features

• Usually asymptomatic
• Incidental finding on imaging
• Rarely pathological fracture

Location

• Distal femur
• Proximal tibia
• Other long Bones

Imaging

• Plain radiograph: eccentric radiolucent lesion in metaphyseal cortex
• Well-defined sclerotic margin

Pathology

• Benign fibroblasts arranged in fascicles
• Absence of atypia

Genetics

Sporadic

Treatment

• Observation: most regress spontaneously
• Excision if symptomatic or causing pathological fracture

Prognosis

Excellent: typically involute by adulthood

Key Points

• Benign self-limited lesion
• Observation standard of care

Workup - Blood Tests

No blood tests required

Workup - Local Imaging

Plain radiograph: characteristic appearance sufficient

Workup - Biopsy

Rarely required

Workup - Staging

No staging required

Workup - Other

Follow-up imaging only if rapid growth or symptoms