Neonatal osteofibrous dysplasia: Synchronous tibial and fibular involvement is common

Abstract

Osteofibrous dysplasia is a rare non-malignant fibro-osseous bone tumour, first described and characterised under this name by Campanacci in 1976. It is most commonly encountered in the tibia of children and young adults, but less frequently seen in the neonate with only few prior reports in the literature. We report a case of neonatal congenital osteofibrous dysplasia, presenting with unilateral limb deformity at birth. Radiographs demonstrated well-defined mixed lytic-sclerotic lesions, in a previously unreported distribution in this age-group, confined to the distal metadiaphysis of the affected tibia and fibula. Open surgery was performed for deformity correction, with tissue biopsy confirming the radiographically-suspected diagnosis. We present the up-to-date clinical, radiological and pathological findings in this case of a rare pathology with some novel features, within this age group, in disease distribution and consequent radiographic appearances. OFD should be considered in the differential of similar congenital deforming bone lesions of the lower limb. We also review the small number of previously published cases of congenital OFD in the neonate, noting in particular that the frequency of ipsilateral fibular involvement appears to be higher than that observed in older patients.

Figure 1.

Clinical photograph demonstrating the left lower limb deformity noted at birth

Figure 2.

Anteroposterior (A) and lateral radiographs (B) of the left ankle at presentation (on day of birth) demonstrating mixed lytic-sclerotic lesions of the distal tibia and fibula with associated deformity

Figure 3.

Photomicrographs, H&E stained section, x10 magnification. Demonstrating (A): tumour composed of irregular woven bone trabeculae with conspicuous osteoblastic rimming [*]. Intervening collagenous stroma with monotonous spindle cells. (B): Further section showing the stroma composed of bland spindle cells embedded in a collagenous matrix. Focal ossification is noted. Cytokeratin MNF116 stain showing single dispersed positive cells [*], confirming the diagnosis of congenital osteofibrous dysplasia

Figure 4.

Anteroposterior (A) and lateral radiographs (B) of the affected limb (aged 14 months). There is post-surgical new bone formation with defined cortices of the distal tibia and fibula, and reactive sclerosis at the osteotomy sites. The focal lesion has a non-aggressive radiological appearance and the proximal diaphyses remain spared. (C): Clinical photograph demonstrating orthogonal alignment of the limb and minimal visual deformity as compared with Figure 1