Injuries and wounds: immersion foot: practice question

A Forensic Medicine 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

Forensic Medicine · Injuries and wounds: immersion foot

Sample item

Shipwreck survivors spend three days in a lifeboat with their feet constantly wet in cold seawater. Their feet become numb, swollen and pale, then red and painful, with blistering. The air temperature never fell below freezing. What is the diagnosis?

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

The answer and the reasoning

C. Immersion foot, a non-freezing cold injury

Immersion (trench) foot follows prolonged exposure to cold and wet conditions at temperatures above freezing, causing vasoconstriction and nerve and tissue damage. Frostbite needs actual freezing of tissue. Chilblains are itchy inflammatory patches from repeated cold exposure of the skin.

Option by option

  • A. Chilblains

    Chilblains are small itchy inflamed patches and do not cause swelling of the whole foot after days of immersion.

  • B. Raynaud phenomenon

    Raynaud phenomenon is episodic colour change of digits and is not caused by prolonged wet exposure.

  • C. Immersion foot, a non-freezing cold injury (correct)

    Correct. Long wet cold exposure above freezing produces this non-freezing injury.

  • D. Frostbite

    Frostbite requires freezing temperatures and ice crystal formation in tissue.

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 Forensic Medicine questions

Questions about this Forensic Medicine question

What is the answer to this Forensic Medicine question?

The best answer is C, Immersion foot, a non-freezing cold injury. Immersion (trench) foot follows prolonged exposure to cold and wet conditions at temperatures above freezing, causing vasoconstriction and nerve and tissue damage.

Why is "Chilblains" not the answer?

Chilblains are small itchy inflamed patches and do not cause swelling of the whole foot after days of immersion.

Why is "Raynaud phenomenon" not the answer?

Raynaud phenomenon is episodic colour change of digits and is not caused by prolonged wet exposure.

Why is "Frostbite" not the answer?

Frostbite requires freezing temperatures and ice crystal formation in tissue.

What concept does this question test?

It tests Injuries and wounds: immersion foot in Forensic Medicine. Frostbite needs actual freezing of tissue. Chilblains are itchy inflammatory patches from repeated cold exposure of the skin.

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 Injuries and wounds: immersion foot?

Learn postmortem changes with their timelines, and toxicology as poison, sign, test and antidote. Then use the flashcards and the other Forensic Medicine 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.