A lytic bone lesion on X-ray should be approached systematically using five steps: patient age (the single most powerful clue — under 20 favours benign lesions, over 40 mandates excluding metastasis and myeloma first), location within the bone (epiphysis, metaphysis, or diaphysis each suggest specific diagnoses), zone of transition (narrow/sclerotic rim = benign; permeative = highly aggressive), periosteal reaction (solid = benign; Codman's triangle/sunburst/onion-skin = malignant), and matrix pattern (chondroid arcs-and-rings, osteoid fluffy/cloud-like, ground-glass for fibrous dysplasia, or no matrix). Investigation follows a stepwise sequence — MRI before biopsy, staging CT for suspected malignancy, bone scan for multifocal disease, and targeted bloods — and biopsy must always be planned by the treating oncological surgeon in the line of the definitive surgical incision, as a misplaced biopsy can contaminate compartments and mandate amputation.
What is the most powerful diagnostic clue when evaluating a lytic bone lesion?
Which lytic bone lesion is most likely in a 25-year-old patient presenting with a metaphyseal lesion?
Which zone of transition indicates a benign lytic bone lesion?
What type of periosteal reaction is typically associated with malignant lytic bone lesions?
In the evaluation of a lytic bone lesion, which matrix pattern is most suggestive of an osteosarcoma?
A 45-year-old patient presents with a lytic bone lesion in the diaphysis of the femur. What should be the first step in approaching this lesion?
Which of the following lesions is most likely to present with a lytic bone lesion in a patient under 20 years of age?
What is the recommended sequence of imaging for suspected malignant lytic bone lesions?
Which of the following features suggests a benign lytic lesion when observed on X-ray?
Which type of biopsy is always preferred for lytic bone lesions, and why?
