Bone tumours: unicameral bone cyst: practice question

A Orthopaedics question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

Try it

Orthopaedics · Bone tumours: unicameral bone cyst

Sample item

A child has a pathological fracture through a central lucent lesion of the proximal humerus. A small bone fragment is seen lying in the dependent part of the cyst. What is this sign?

ADouble density sign of osteoid osteomaBFallen fragment sign of a simple (unicameral) bone cystCSoap-bubble sign of giant cell tumourDRim sign of an aneurysmal bone cyst

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

B. Fallen fragment sign of a simple (unicameral) bone cyst

The fallen fragment sign is a fractured cortical piece that falls to the dependent portion of a fluid-filled cyst and is pathognomonic of a simple bone cyst. Treatment may include injection of steroid or bone marrow, or curettage and grafting.

Option by option

A. Double density sign of osteoid osteoma
Double density sign is a bone scan feature.
B. Fallen fragment sign of a simple (unicameral) bone cyst (correct)
Correct. The fallen fragment sign indicates a unicameral cyst.
C. Soap-bubble sign of giant cell tumour
Soap-bubble sign is typical of giant cell tumour.
D. Rim sign of an aneurysmal bone cyst
An ABC is eccentric with fluid-fluid levels.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

Questions about this Orthopaedics question

What is the answer to this Orthopaedics question?

The best answer is B, Fallen fragment sign of a simple (unicameral) bone cyst. The fallen fragment sign is a fractured cortical piece that falls to the dependent portion of a fluid-filled cyst and is pathognomonic of a simple bone cyst.

Why is "Double density sign of osteoid osteoma" not the answer?

Double density sign is a bone scan feature.

Why is "Soap-bubble sign of giant cell tumour" not the answer?

Soap-bubble sign is typical of giant cell tumour.

Why is "Rim sign of an aneurysmal bone cyst" not the answer?

An ABC is eccentric with fluid-fluid levels.

What concept does this question test?

It tests Bone tumours: unicameral bone cyst in Orthopaedics. Treatment may include injection of steroid or bone marrow, or curettage and grafting.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Bone tumours: unicameral bone cyst?

Pair each fracture with its classic complication and nerve injured. Then use the flashcards and the other Orthopaedics questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.