Metabolic bone disease: salt-and-pepper skull: 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.

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Orthopaedics · Metabolic bone disease: salt-and-pepper skull

Sample item

A 45-year-old woman has renal stones and bone pain. A skull radiograph shows fine granular mottling. Serum calcium is high, phosphate is low and PTH is raised. What is the diagnosis?

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

The answer and the reasoning

B. Primary hyperparathyroidism

Subperiosteal and trabecular resorption of the skull produces a salt-and-pepper appearance. High calcium with low phosphate and raised PTH indicates primary hyperparathyroidism. In secondary hyperparathyroidism the calcium is low or normal.

Option by option

  • A. Paget disease of bone

    Paget disease has normal calcium and phosphate and a thickened cotton-wool skull.

  • B. Primary hyperparathyroidism (correct)

    Correct. High calcium, low phosphate and high PTH with a granular skull indicate primary hyperparathyroidism.

  • C. Fibrous dysplasia

    Fibrous dysplasia has normal biochemistry and a ground-glass lesion.

  • D. Multiple myeloma

    Myeloma gives discrete punched-out lesions rather than fine mottling.

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.

More Orthopaedics questions

Questions about this Orthopaedics question

What is the answer to this Orthopaedics question?

The best answer is B, Primary hyperparathyroidism. Subperiosteal and trabecular resorption of the skull produces a salt-and-pepper appearance.

Why is "Paget disease of bone" not the answer?

Paget disease has normal calcium and phosphate and a thickened cotton-wool skull.

Why is "Fibrous dysplasia" not the answer?

Fibrous dysplasia has normal biochemistry and a ground-glass lesion.

Why is "Multiple myeloma" not the answer?

Myeloma gives discrete punched-out lesions rather than fine mottling.

What concept does this question test?

It tests Metabolic bone disease: salt-and-pepper skull in Orthopaedics. High calcium with low phosphate and raised PTH indicates primary hyperparathyroidism. In secondary hyperparathyroidism the calcium is low or normal.

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 Metabolic bone disease: salt-and-pepper skull?

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.