Fractures: scaphoid blood supply: 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 · Fractures: scaphoid blood supply

Sample item

Avascular necrosis is most likely after a fracture through which part of the scaphoid, and why?

AProximal pole, because the blood supply enters distally and runs retrogradeBWaist, because both poles are supplied only from the waistCTubercle, because it lies within the articular cartilageDDistal pole, because it has no ligamentous attachments

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

The answer and the reasoning

A. Proximal pole, because the blood supply enters distally and runs retrograde

The scaphoid receives most of its blood supply from the dorsal carpal branch of the radial artery entering at the distal part and flowing retrograde. A proximal pole fracture therefore leaves the fragment ischaemic with a high risk of nonunion and avascular necrosis.

Option by option

A. Proximal pole, because the blood supply enters distally and runs retrograde (correct)
Correct. Retrograde supply makes the proximal pole most vulnerable.
B. Waist, because both poles are supplied only from the waist
Both poles do not depend on the waist; supply enters at the distal part.
C. Tubercle, because it lies within the articular cartilage
Tubercle fractures usually unite because the blood supply is rich.
D. Distal pole, because it has no ligamentous attachments
The distal pole is well supplied by the entering vessels.

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, Proximal pole, because the blood supply enters distally and runs retrograde. The scaphoid receives most of its blood supply from the dorsal carpal branch of the radial artery entering at the distal part and flowing retrograde.

Why is "Waist, because both poles are supplied only from the waist" not the answer?

Both poles do not depend on the waist; supply enters at the distal part.

Why is "Tubercle, because it lies within the articular cartilage" not the answer?

Tubercle fractures usually unite because the blood supply is rich.

Why is "Distal pole, because it has no ligamentous attachments" not the answer?

The distal pole is well supplied by the entering vessels.

What concept does this question test?

It tests Fractures: scaphoid blood supply in Orthopaedics. A proximal pole fracture therefore leaves the fragment ischaemic with a high risk of nonunion and avascular necrosis.

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 Fractures: scaphoid blood supply?

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.