Presentation
Painless swelling of arm.
Patient Data
Age: 18 years
Gender: Male
From the case:
Osteochondroma - humerus
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There is a sessile bony mass arising from the proximal metaphyso-diaphyseal region of the right humerus, with no periosteal reaction seen.
From the case:
Osteochondroma - humerus
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There is a sessile exostosis projection from anteromedial aspect of proximal metaphyso-diaphyseal of humerus, measured about 53 x 33 x 32 mm in diameters. The cartilaginous cap is measured up to 5 mm in thickness.
Bone marrow signal intensity of the mother bone, the muscles and tendons are normal.
Case Discussion
Plain film and MRI features are of a sessile osteochondroma. MRI is the best imaging modality to assess cartilage thickness. A cartilage cap of over 1.5 cm in thickness raises suspicion of a malignant degeneration.