Presentation
Lump felt on the medial aspect of the knee
Patient Data
Age: 15 years
Gender: Male
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An osteochondroma arises from the medial aspect of the distal femoral diaphysis, extending away from the joint. It has a small cartilage cap, and associated with no pathological fracture. Minimal surrounding muscular edema most likely mechanical in nature.
Case Discussion
Osteochondromas can be single, or multiple in cases of hereditary multiple exostoses/diaphyseal aclasis.
Malignant transformation to a chondrosarcoma is suggested if the cartilage cap measures more than 15mm in thickness and/or there is continued growth in size after skeletal maturity 1.