Abdomen and pelvis: 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 · Abdomen and pelvis

Sample item

A woman has intense pain during defaecation with a streak of blood and a tear seen at the 6 o'clock position in the lithotomy position. Why is the posterior midline the usual site?

ARich lymphatic drainageBDrainage into the portal systemCPresence of the anal columnsDPoor blood supply and less support from the sphincter fibres

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

The answer and the reasoning

D. Poor blood supply and less support from the sphincter fibres

The posterior midline of the anal canal has the weakest support from the external sphincter and a poorer blood supply, so it tears with hard stools. The pain is due to somatic innervation below the pectinate line and sphincter spasm.

Option by option

A. Rich lymphatic drainage
Lymphatic drainage does not determine the site of fissures.
B. Drainage into the portal system
Portal drainage relates to the upper rectum and is not the explanation.
C. Presence of the anal columns
Anal columns are above the pectinate line and unrelated to the tear.
D. Poor blood supply and less support from the sphincter fibres (correct)
Correct. Less support and poor vascularity make the posterior midline susceptible to tears.

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 Anatomy question

What is the answer to this Anatomy question?

The best answer is D, Poor blood supply and less support from the sphincter fibres. The posterior midline of the anal canal has the weakest support from the external sphincter and a poorer blood supply, so it tears with hard stools.

Why is "Rich lymphatic drainage" not the answer?

Lymphatic drainage does not determine the site of fissures.

Why is "Drainage into the portal system" not the answer?

Portal drainage relates to the upper rectum and is not the explanation.

Why is "Presence of the anal columns" not the answer?

Anal columns are above the pectinate line and unrelated to the tear.

What concept does this question test?

It tests Abdomen and pelvis in Anatomy. The pain is due to somatic innervation below the pectinate line and sphincter spasm.

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 Abdomen and pelvis?

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.