Presentation
Focal bone swelling.
Patient Data
Age: 3
Gender: Male
From the case:
Osteochondroma - humerus
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Typical appearance of a humeral exostosis, a common finding in children presenting with a mass in the extremity. There is a cortical and medullary external focal protrusion with typical continuity of the lesion with the underlying native bone.
An ultrasound examination would show an overlying hyaline cartilage cap (osteocartilaginous exostosis/osteochondroma) .
Case Discussion
An exostosis (osteochondroma) is the most common benign bone tumour, that grows from metaphysis of bones that undergo endochondral bone formation. This case is a classic example of a sessile osteochondroma.