Non-ossifying fibroma of distal tibia: case report

Abstract

Non-ossifying fibroma is a benign fibrohistiocytic lesion most commonly seen in the metaphyseal region in children. It usually doesn’t present with any symptoms. As the bone grows and undergoes remodeling, the lesion tends to vanish and get substituted with healthy bone. Nonetheless, the lesion can debilitate the affected bone, leading to a potential fracture. Here, we report a case of non-ossifying fibroma in the metaphyseal region of the tibia in a 13-year female. The patient presented with complaints of pain in the left leg for 5 months and underwent radiological investigation showing a well-defined, multi-loculated, expansile, radiolucent, lytic lesion with a thin sclerotic margin in the meta-diaphyseal region of the distal tibia, for which extended bone curettage with bone grafting was performed. The sample was sent for histopathological examination, which showed bony trabeculae with bits of tumor composed of spindle cells with elongated nuclei and scant cytoplasm, arranged in a storiform pattern along with many scattered multinucleate giant cells and foamy histiocytes suggestive of non-ossifying fibroma. Post operatively, non-weight bearing mobilization was advised for 4 weeks. Most non-ossifying fibromas were diagnosed in childhood to late adolescence, found incidentally, and clinically asymptomatic. Most distal tibial non-ossifying fibromas (NOFs) tend to transpire at a specific anatomical site located at the far end of the interosseous membrane. The prognosis for NOFs is typically excellent with a low risk of recurrence.