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OrthoVellum

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Oncology
intermediate
X-Type

Unicameral Bone Cyst (Simple Bone Cyst)

Benign Bone Lesions

An 8-year-old boy presents with arm pain after minor trauma during a fall. Radiographs show a well-defined, central, metaphyseal lytic lesion in the proximal humerus with thinned cortices and a pathological fracture. The lesion abuts the physis. There is no periosteal reaction or soft tissue mass. A fragment of cortical bone is noted lying within the dependent portion of the cyst. Regarding unicameral bone cyst:

Mark each as TRUE or FALSE

A

Unicameral bone cyst (UBC, also called simple bone cyst) is a benign, fluid-filled, unilocular lesio...

B

Radiographically, UBC appears as a central, well-defined, metaphyseal lytic lesion with thinned but ...

C

UBC is a malignant lesion requiring aggressive treatment; it primarily affects elderly patients; ecc...

D

Many UBCs present with pathological fracture; fractures may heal the cyst in 10-15% of cases (more c...

E

Active cysts (adjacent to physis) have higher recurrence rates (50-60%) compared to latent cysts (10...

Answer the questions to see explanations

Click T (True) or F (False) for each option