Presentation
6 month history of left hip pain. Normal US hips and knees. Normal x-ray pelvis and knee 3 months ago.
Patient Data
Age: 7 years
Gender: Male
From the case:
Perthes disease
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The left femoral epiphysis is small and more sclerotic than the right. In addition, there is linear subchondral lucency. Appearances of a subchondral fracture in avascular necrosis.
From the case:
Perthes disease
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Zoomed image of the left hip. The subchondral lucency is clearly demonstrated.
Case Discussion
There are a couple of features of avascular necrosis in this case (small, sclerotic epiphysis with linear subchondral lucency). The repeat imaging in this case is key to making the diagnosis - despite previously normal imaging.