Presentation
Fall and pain.
Patient Data
Age: 10 years
From the case:
Unicameral bone cyst with fracture - humerus
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Well circumscribed, expansile, lucent lesion in the metaphysis and proximal diaphysis. Through the inferior aspect of the lesion a pathological fracture is noted, coursing obliquely downwards from medial to lateral.
From the case:
Unicameral bone cyst with fracture - humerus
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A prominent trabeculation through the upper part of the lesion on x-ray mimics a multiloculated lesion, however unilocularity is confirmed on CT.
CT obtained sometimes later confirms that the lesion is well circumscribed and unilocular.
Case Discussion
Features that are consistent with a unicameral bone cyst with a pathological fracture and fallen fragment sign.