What kind of lysis is described in the caudal aspect of the distal metaphysis?

• A. Severe moth-eaten lysis with cortical breach
• B. Mild moth-eaten and expansile lysis in the caudal aspect of the distal metaphysis
• C. Sclerotic lesion with no lysis
• D. Ground-glass lucency

Answer: (B)

Lytic patterns on radiographs tell you how aggressively a lesion is destroying bone and how the cortex is responding. “Moth-eaten” describes multiple irregular lucencies with ill-defined margins, suggesting an active, destructive process. When a lesion is described as expansile, the bone is being pushed outward, thinning the cortex as the lesion grows. Putting these together in the caudal aspect of the distal metaphysis points to a lesion that is destructive but not fully breaking through the cortex, and it is localized to that metaphyseal region.

That combination—mild moth-eaten destruction with expansion in the distal metaphysis—best fits the described scenario. The other patterns imply either more aggressive cortical breach, no lytic destruction, or a different radiographic texture (ground-glass), which are not as consistent with the described findings.