system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
12 years male came with swelling of lower end tibia which is surounded by rim of reactive bone. what is most likely diagnosis?
assistant
The correct answer is  Brodie&;s abscess : seen in immunocompetent host 1. It is along standing localized pyogenic abscess in the bone . 2. It usually involves long bones e.g. upper end of tibia 3. classical brodie&;s abscess looks like a small walled off cavity in bone with little or no periosteal reaction. usual isolated oganism is Staphlococcus aureus ref : maheswari 9th ed