Bone and joint infections: tuberculous versus pyogenic spondylodiscitis: 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 · Bone and joint infections: tuberculous versus pyogenic spondylodiscitis

Sample item

MRI of the thoracic spine in a young adult with months of back pain and weight loss shows involvement of three contiguous vertebrae and a large paravertebral collection. Which feature favours tuberculosis over pyogenic spondylodiscitis?

ADisc height preserved until late with a large abscessBSingle-level disease with minimal soft tissue collectionCAbrupt onset with high fever and marked neutrophiliaDEarly marked disc loss with endplate erosion at one level

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

The answer and the reasoning

A. Disc height preserved until late with a large abscess

Tuberculosis lacks proteolytic enzymes, so the disc is relatively preserved until late, while multilevel disease and large paravertebral or epidural abscesses are common. Pyogenic infection destroys the disc and endplate early and tends to be acute and limited to one level.

Option by option

A. Disc height preserved until late with a large abscess (correct)
Correct. Late disc involvement with large abscesses and multilevel spread is typical of tuberculosis.
B. Single-level disease with minimal soft tissue collection
Single-level disease with little soft tissue collection is less typical of tuberculosis.
C. Abrupt onset with high fever and marked neutrophilia
Abrupt febrile onset with neutrophilia points to pyogenic infection.
D. Early marked disc loss with endplate erosion at one level
Early disc destruction with endplate erosion is the pattern of pyogenic infection.

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 A, Disc height preserved until late with a large abscess. Tuberculosis lacks proteolytic enzymes, so the disc is relatively preserved until late, while multilevel disease and large paravertebral or epidural abscesses are common.

Why is "Single-level disease with minimal soft tissue collection" not the answer?

Single-level disease with little soft tissue collection is less typical of tuberculosis.

Why is "Abrupt onset with high fever and marked neutrophilia" not the answer?

Abrupt febrile onset with neutrophilia points to pyogenic infection.

Why is "Early marked disc loss with endplate erosion at one level" not the answer?

Early disc destruction with endplate erosion is the pattern of pyogenic infection.

What concept does this question test?

It tests Bone and joint infections: tuberculous versus pyogenic spondylodiscitis in Orthopaedics. Pyogenic infection destroys the disc and endplate early and tends to be acute and limited to one level.

How hard is this question?

We tag it as a multi-step question: it asks you to combine more than one idea. 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 and joint infections: tuberculous versus pyogenic spondylodiscitis?

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.