Osteofibrous dysplasia is a distinct clinical entity affecting the middle third of the tibia, with eccentric lytic lesion and typically with some osteoblastic rimming.
It is also called ossifying fibroma or Campanacci’s lesion.
The exact cause remains unknown, however, several theories have been proposed.
Result of excessive resorption of bone with the fibrous repair of the defect.
Congenital lesion or variant of fibrous dysplasia
Abnormal blood circulation in the periosteum
Reactive process secondary to adamantinoma or a precursor of adamantinoma
Osteofibrous dysplasia almost always appears in the first decade of life. 2/3rd of lesion noted before 5 years of age.
It is slightly more common in boys.
Tibia is almost always involved and ipsilateral fibula may be affected. Bilateral involvement, radial, and ulnar lesion are reported.
The common presenting complaint is a firm swelling localized over the tibia with associated mild to moderate anterior tibial bowing.
It is painless unless there is a co-existing pathological fracture.
Plain radiographs of the affected bone will demonstrate the anterior intracortical involvement of the middle third of the tibia.
The overlying cortex invariably thinned, expanded, or even absent.
Borders are sclerotic and soap bubble appearance.
There will be no soft tissue expansion or periosteal reaction.
The biopsy of the lesion is diagnostic.
Initial treatment during the infancy and toddler period is bracing and observation.
Surgical excision and stabilization are indicated for progressive bowing or when there is a pathological fracture.
Another surgical option includes curettage, bone graft substitute, stabilization, and intralesional bisphosphonates.
Osteofibrous dysplasia is a benign fibrous tumor with the potential for local aggressive behavior.
High incidence of local recurrence and progression is seen when operated early in life. It also recurs frequently following curettage or subperiosteal resection.
Rare cases may progress to adamantinoma.