[Juxtacortical osteosarcoma of the radius in a child].

The authors report a rare case of juxtacortical osteosarcoma of the radius in a child. The diagnosis and treatment were delayed because of misleading and wrongly reassuring radiological and histological aspects. The 12-year-old boy was admitted for a tumefaction of the proximal extremity of the right radius noticed after trauma. Physical examination showed a hard and slightly painful swelling. Xrays showed an irregular osseous mass developed from the superior metaphysis of the radius and encircling it. MRI showed a juxtacortical tumor with medullary involvement. A biopsy concluded to a fracture callus. Ten months later, the tumor became painful and homogeneous, regular and well defined on Xrays. A repeat biopsy showed juxtacortical osteosarcoma. Enbloc resection of the tumor was done. After a follow-up of 2 years, the child is alive without recurrence and metastasis and with a satisfactory function of the upper limb.