Wrist: scaphoid fracture: practice question

A Anatomy 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

Anatomy · Wrist: scaphoid fracture

Sample item

A 22-year-old man falls on an outstretched hand and has tenderness in the anatomical snuffbox. An initial radiograph is normal, and a later one shows a waist fracture of the scaphoid. Which complication is most likely, and what is the anatomical reason?

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

The answer and the reasoning

A. Avascular necrosis of the proximal fragment, because the blood supply enters distally and runs retrograde

The scaphoid receives most of its blood from branches of the radial artery that enter through the distal part and tubercle and run retrograde. A fracture through the waist or proximal pole can therefore deprive the proximal fragment of supply, causing delayed union, non-union and avascular necrosis. The snuffbox contains the radial artery and the superficial radial nerve branches, not the median nerve.

Option by option

  • A. Avascular necrosis of the proximal fragment, because the blood supply enters distally and runs retrograde (correct)

    Correct. The proximal fragment is left without its retrograde blood supply.

  • B. Median nerve compression, because the nerve lies in the snuffbox

    The median nerve lies in the carpal tunnel, not in the snuffbox.

  • C. Radial artery thrombosis, because the artery is fixed to the scaphoid tubercle

    The radial artery crosses the snuffbox but is not usually thrombosed by a scaphoid fracture.

  • D. Avascular necrosis of the distal fragment, because the blood supply enters proximally

    The distal fragment retains the entering vessels, so it remains viable.

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 Anatomy questions

Questions about this Anatomy question

What is the answer to this Anatomy question?

The best answer is A, Avascular necrosis of the proximal fragment, because the blood supply enters distally and runs retrograde. The scaphoid receives most of its blood from branches of the radial artery that enter through the distal part and tubercle and run retrograde.

Why is "Median nerve compression, because the nerve lies in the snuffbox" not the answer?

The median nerve lies in the carpal tunnel, not in the snuffbox.

Why is "Radial artery thrombosis, because the artery is fixed to the scaphoid…" not the answer?

The radial artery crosses the snuffbox but is not usually thrombosed by a scaphoid fracture.

Why is "Avascular necrosis of the distal fragment, because the blood supply e…" not the answer?

The distal fragment retains the entering vessels, so it remains viable.

What concept does this question test?

It tests Wrist: scaphoid fracture in Anatomy. A fracture through the waist or proximal pole can therefore deprive the proximal fragment of supply, causing delayed union, non-union and avascular necrosis. The snuffbox contains the radial artery and the superficial radial nerve branches, not the median nerve.

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 Wrist: scaphoid fracture?

Learn every nerve by its route, its muscles and what a lesion looks like at the bedside. That one habit answers a large share of questions. Then use the flashcards and the other Anatomy 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.