Q2: What are your differentials for this lesion?

A2: Your differentials should include infection, osteoid osteoma, and eosinophilic granuloma (yes, I am aware that you haven’t studied tumors yet, but please keep this radiographic appearance in mind). In this case, the lesion is a Brodie’s abscess and the sclerosis is reactive in nature. Also, the periosteal response should lean you away from an aggressive tumor as the cause.