Intramedullary osteoblastoma of the femur: a case report.

INTRODUCTION

Osteoblastoma is a rare primary bone tumour, and the lesions are typically intracortical affecting long-bone metaphysis and the posterior spine. The histological hallmark is characteristic networks of trabeculated woven bone, usually lined by osteoblasts within a vascularised stroma. This case report details an unusual case of an intramedullary osteoblastoma of the femur.

CASE PRESENTATION: A 22-year-old male presented with an eight-month history of right knee pain on a background of a previous distal tibia non-ossifying fibroma. The patient underwent cross-sectional imaging, and a biopsy was obtained confirming a lesion in the distal femoral diametaphysis. MRI showed multiple internal fluid levels and septations with a sclerotic rim and associated marrow oedema, cortical sclerosis, and periosteal soft tissue oedema. Subsequent biopsy provided histological confirmation of osteoblastoma.

CONCLUSION

This case is presented to highlight the rare anatomical location for osteoblastoma: in the medullary canal of the distal femur.