Scurvy
- Radiologic findings in infantile scurvy are diagnostic.
- The characteristic radiologic changes occur at the growth cartilage-shaft junction of bones with rapid growth. The knee joint, wrist, and sternal ends of the ribs are typical sites of involvement.
- Radiologic diagnosis of scurvy is based on the following specific changes:
- In the early phase of scurvy, the cortex becomes thin and the trabecular structure of the medulla atrophies and develops a ground-glass appearance.
- The zone of provisional calcification becomes dense and widened, and this zone is referred to as the white line of Fränkel.
- The epiphysis also shows cortical thinning and the ground-glass appearance (Wimberger sign).
- As scurvy becomes advanced, a zone of rarefaction occurs at the metaphysis under the white line. The zone of rarefaction typically involves the lateral aspects of the white line, resulting in triangular defects called the corner sign of Park. This area has multiple microscopic fractures and may collapse with impaction of the calcified cartilage onto the shaft.
- The lateral aspect of the calcified cartilage can project as a spur(pelken spur).
- Subperiosteal hemorrhages are not visualized in the active phase. With healing, they become calcified and are readily observed.