Anatomy
10 questionsIdentify the nerve passing through the Triangle of Doom:
Which artery shown here should be avoided during paracentesis?
Which is correct sequence about the blood supply of the primitive gut?
The area marked as $X$ was selected for gastrostomy. Which of the following statements is incorrect about this area? (Recent NEET Pattern 2016-17)
Which nerve marked as $X$ is shown in the image given below? (Recent NEET Pattern 2016-17)
Which of the following blood vessels is Drummond's Artery? (Recent NEET Pattern 2016-17)
Which of the following is correct about the image shown below?
Identify the structure marked as X in the specimen of left cubital fossa
The following image of posterior abdominal wall and pelvic inlet shows a structure marked as X. Identify it:
Which is correct about the markings shown on the left popliteal fossa? (Recent NEET Pattern 2016-17)
NEET-PG 2017 - Anatomy NEET-PG Practice Questions and MCQs
Question 311: Identify the nerve passing through the Triangle of Doom:
- A. Genital branch of genitofemoral nerve
- B. Femoral branch of genitofemoral nerve (Correct Answer)
- C. Ilio-inguinal nerve
- D. Lateral femoral cutaneous nerve
Explanation: ***Femoral branch of genitofemoral nerve*** - The **Triangle of Doom** is an inverted triangle located inferior to the deep inguinal ring, bounded by the **vas deferens medially** and the **gonadal vessels laterally**. - The **femoral branch of genitofemoral nerve** courses along the **external iliac artery** and passes through or immediately adjacent to the Triangle of Doom. - This nerve is at significant risk during laparoscopic inguinal hernia repair when dissecting within this triangle, making it a critical landmark. - Injury can result in sensory loss over the anterior thigh. *Lateral femoral cutaneous nerve* - The **lateral femoral cutaneous nerve** runs **lateral to the Triangle of Doom**, passing under the lateral aspect of the inguinal ligament near the anterior superior iliac spine. - It does NOT pass through the Triangle of Doom itself. - It provides sensation to the lateral thigh and can be injured during lateral dissection, but is not within the triangle's boundaries. *Genital branch of genitofemoral nerve* - The **genital branch of genitofemoral nerve** courses through the **inguinal canal** alongside the spermatic cord. - It innervates the cremaster muscle and scrotal skin. - It lies more anterior and medial, within the inguinal canal rather than in the Triangle of Doom. *Ilio-inguinal nerve* - The **ilio-inguinal nerve** runs within the inguinal canal parallel to the spermatic cord. - It provides sensation to the groin, perineum, and inner thigh. - It is located superficial to the deep inguinal ring and anterior to the Triangle of Doom structures.
Question 312: Which artery shown here should be avoided during paracentesis?
- A. Superior epigastric artery
- B. Inferior epigastric artery (Correct Answer)
- C. Superior hypogastric artery
- D. Inferior hypogastric artery
Explanation: ***Inferior epigastric artery*** - The image depicts the **inferior epigastric artery** and its branches, which run on the anterior abdominal wall. These vessels are susceptible to injury during paracentesis, particularly if the needle is inserted lateral to the rectus abdominis muscle. - Injury to the inferior epigastric artery can lead to **significant bleeding** and **hematoma formation**, even after careful technique. *Superior epigastric artery* - The **superior epigastric artery** is a continuation of the internal thoracic artery and supplies the upper rectus abdominis muscle. It is located more superiorly and less commonly injured during **paracentesis** which is typically performed in the lower abdomen. - While it anastomoses with the inferior epigastric artery, its anatomical position makes it a less likely candidate for direct injury during standard paracentesis procedures which are usually performed below the umbilicus. *Superior hypogastric artery* - The **superior hypogastric artery** (also known as the median sacral artery) originates from the posterior aspect of the aorta and is involved in the arterial supply of structures within the pelvis. - This artery is located **deep within the pelvis**, far from the anterior abdominal wall where paracentesis is performed, making it anatomically irrelevant to this procedure. *Inferior hypogastric artery* - The term **inferior hypogastric artery** is not a standard anatomical term for a major artery; the primary pelvic arterial supply is from the internal iliac artery, sometimes referred to as the hypogastric artery, which branches into numerous smaller vessels. - Regardless of specific nomenclature, any such vessel would be located **deep in the pelvis** and not in the abdominal wall where injury during paracentesis would be a concern.
Question 313: Which is correct sequence about the blood supply of the primitive gut?
- A. Foregut= Celiac trunk, Midgut= Superior mesenteric artery, Hindgut= inferior mesenteric artery (Correct Answer)
- B. Foregut= Superior mesenteric artery, Midgut= Celiac trunk, Hindgut= inferior mesenteric artery
- C. Foregut= Celiac trunk, Midgut= Superior mesenteric artery, Hindgut= ileocolic artery
- D. Foregut= Celiac trunk, Midgut= Inferior mesenteric artery, Hindgut= inferior mesenteric artery
Explanation: ***Foregut= Celiac trunk, Midgut= Superior mesenteric artery, Hindgut= inferior mesenteric artery*** - The primitive gut is divided embryologically into three main sections: **foregut, midgut, and hindgut**, each supplied by a distinct major artery originating from the dorsal aorta [1]. - The **celiac trunk** supplies the derivatives of the foregut, the **superior mesenteric artery (SMA)** supplies the midgut derivatives, and the **inferior mesenteric artery (IMA)** supplies the hindgut derivatives [1]. *Foregut= Superior mesenteric artery, Midgut= Celiac trunk, Hindgut= inferior mesenteric artery* - This option incorrectly assigns the **superior mesenteric artery** to the foregut and the celiac trunk to the midgut. - The celiac trunk supplies the foregut, and the superior mesenteric artery supplies the midgut. *Foregut= Celiac trunk, Midgut= Superior mesenteric artery, Hindgut= ileocolic artery* - While the foregut and midgut associations are correct, the **ileocolic artery** is a branch of the superior mesenteric artery [1] and supplies only a portion of the midgut and hindgut transition, not the entire hindgut. - The main artery for the entire hindgut is the **inferior mesenteric artery** [1]. *Foregut= Celiac trunk, Midgut= Inferior mesenteric artery, Hindgut= inferior mesenteric artery* - This option correctly identifies the **celiac trunk** for the foregut but incorrectly assigns the **inferior mesenteric artery** to the midgut. - The **superior mesenteric artery** is the primary blood supply for the midgut.
Question 314: The area marked as $X$ was selected for gastrostomy. Which of the following statements is incorrect about this area? (Recent NEET Pattern 2016-17)
- A. Bounded on right by inferior border of liver
- B. Bounded on left by costal margin (Correct Answer)
- C. Bounded inferiorly by first part of duodenum
- D. Preferred site for gastrostomy
Explanation: ***Bounded on left by costal margin*** - This statement is marked as incorrect in this context because the more **precise anatomical term** for the left boundary of **Labbé's triangle (gastric triangle)** is the **left costal cartilage** (specifically 7th, 8th, and 9th costal cartilages). - While "costal margin" and "costal cartilage" are often used interchangeably in clinical practice, this question tests the more specific anatomical nomenclature. - The left costal margin is formed by these costal cartilages, but for precise anatomical description of Labbé's triangle, the term "left costal cartilage" is preferred. *Bounded on right by inferior border of liver* - This statement is correct. **Labbé's triangle**, a safe area for gastrostomy, is bounded on its **right side by the inferior border of the liver**. - This anatomical landmark helps define the region where the anterior wall of the stomach is accessible for surgical procedures without traversing other organs. *Bounded inferiorly by first part of duodenum* - This statement is correct. The **transpyloric plane** (at the level of L1 vertebra), which corresponds to the level of the first part of the duodenum, forms the **inferior boundary** of Labbé's triangle. - This boundary ensures that the gastrostomy site is on the body of the stomach and avoids damage to the duodenum. *Preferred site for gastrostomy* - This statement is correct. The region marked 'X' refers to **Labbé's triangle**, which is anatomically considered the **preferred and safest site for gastrostomy**. - This triangular area allows direct access to the anterior wall of the stomach without crossing other vital organs (liver, colon), reducing surgical risks and complications.
Question 315: Which nerve marked as $X$ is shown in the image given below? (Recent NEET Pattern 2016-17)
- A. Nerve of Laterjet
- B. Criminal nerve of Grassi (Correct Answer)
- C. Crow's feet
- D. Celiac trunk
Explanation: ***Correct: Criminal nerve of Grassi*** - The image shows the **vagal innervation to the stomach**. The nerve marked 'X' is a **posterior gastric nerve** branch that innervates the **fundus** and is often referred to as the criminal nerve of Grassi due to its implication in **recurrent ulceration if not transected during vagotomy**. - This nerve is part of the **posterior vagal trunk** and specifically innervates the posterior aspect of the fundus and body of the stomach. Its omission during a vagotomy can lead to continued acid secretion. *Incorrect: Nerve of Laterjet* - The nerve of Laterjet refers to the **anterior and posterior gastric nerves** that run along the **lesser curvature** of the stomach. - These nerves primarily innervate the **body and antrum** of the stomach and control acid secretion from the parietal cells. *Incorrect: Crow's feet* - "Crow's feet" refers to the **pyloric branches** of the anterior and posterior nerves of Laterjet, which ramify around the **pylorus**. - These are distinguished from the nerve of Grassi which supplies the fundus. *Incorrect: Celiac trunk* - The celiac trunk is an **artery**, not a nerve. It is a major visceral branch of the aorta that supplies blood to the foregut structures, including the stomach, liver, and spleen. - It does not represent neural innervation as depicted in the image.
Question 316: Which of the following blood vessels is Drummond's Artery? (Recent NEET Pattern 2016-17)
- A. C (Correct Answer)
- B. D
- C. A
- D. B
Explanation: ***C*** - Label C points to the **marginal artery of Drummond**, which is a continuous arterial anastomosis running along the mesenteric border of the large intestine. - This artery provides a crucial **collateral blood supply** to the colon, connecting branches of the superior and inferior mesenteric arteries. *A* - Label A points to branches of the **superior mesenteric artery** supplying the transverse colon, specifically the **middle colic artery** and possibly the **right colic artery**. - These are major contributors to the colon's blood supply but are not individually referred to as Drummond's artery; rather, they anastomose with it. *B* - Label B points to the **superior mesenteric artery** itself, which is the main artery supplying the small intestine, and parts of the large intestine (up to the distal transverse colon). - The superior mesenteric artery is a primary source of blood flow, but Drummond's artery is a separate anastomotic channel. *D* - Label D points to branches of the **inferior mesenteric artery** supplying the descending colon, specifically the **left colic artery**. - This artery contributes to the distal portion of Drummond's artery, but D itself indicates one of the feeding vessels rather than the marginal artery itself.
Question 317: Which of the following is correct about the image shown below?
- A. A = Cisterna magna, B= Posterior nasal aperture
- B. A = Ethmoidal sinus, B= Auditory tube opening
- C. A = Sphenoid sinus, B= Auditory tube opening (Correct Answer)
- D. A = Sella turcica, B= Posterior nasal aperture
Explanation: ***A = Sphenoid sinus, B= Auditory tube opening*** - Label **A** clearly points to the **sphenoid sinus**, an air-filled cavity within the sphenoid bone, located posterior to the nasal cavity and inferior to the sella turcica. - Label **B** indicates the opening of the **auditory (Eustachian) tube** in the lateral wall of the nasopharynx, connecting the nasopharynx to the middle ear. *A = Cisterna magna, B= Posterior nasal aperture* - **Cisterna magna** is a subarachnoid space located posterior to the cerebellum and medulla, not visible at this anterior anatomical location. - The **posterior nasal aperture (choana)** is the opening between the nasal cavity and the nasopharynx, which is located more anteriorly and inferiorly relative to point B. *A = Ethmoidal sinus, B= Auditory tube opening* - The **ethmoidal sinuses** are located anterior to the sphenoid sinus, within the ethmoid bone, and would appear more superior and anterior to where A is located. - While B is correctly identified as the auditory tube opening, A is misplaced for the ethmoidal sinus. *A = Sella turcica, B= Posterior nasal aperture* - The **sella turcica** is a saddle-shaped depression in the sphenoid bone, superior to the sphenoid sinus, which houses the pituitary gland. - The **posterior nasal aperture** is incorrect for B, as explained above.
Question 318: Identify the structure marked as X in the specimen of left cubital fossa
- A. Biceps brachii
- B. Brachial artery (Correct Answer)
- C. Radial recurrent artery
- D. Posterior interosseous nerve
Explanation: ***Brachial artery*** - The structure marked X is a prominent, thick-walled vessel consistent with the **brachial artery**, which passes through the cubital fossa. - The brachial artery is typically found medial to the **biceps brachii tendon** and lateral to the **median nerve** in the cubital fossa. *Biceps brachii* - The **biceps brachii** is a muscle, and while its tendon passes through the cubital fossa, the structure marked X is clearly a vessel, not a muscle or tendon. - The biceps brachii muscle is usually much larger and fleshy, not a defined linear structure like X. *Radial recurrent artery* - The **radial recurrent artery** is a smaller branch arising from the radial artery, which subsequently branches off the brachial artery. - It is significantly smaller and less prominent than the structure marked X, which appears to be a main vessel. *Posterior interosseous nerve* - The **posterior interosseous nerve** is a branch of the radial nerve and is primarily a nerve structure, which appears white/yellowish and thinner than the structure marked X, which is a blood vessel. - It typically winds around the neck of the radius and passes into the posterior compartment of the forearm, not usually as prominently displayed within the cubital fossa in this manner.
Question 319: The following image of posterior abdominal wall and pelvic inlet shows a structure marked as X. Identify it:
- A. Ureter
- B. Superior hypogastric plexus (Correct Answer)
- C. Obturator nerve
- D. Genitofemoral nerve
Explanation: ***Superior hypogastric plexus*** - The structure marked 'X' is a prominent plexus of nerves located anterior to the **aortic bifurcation** and sacral promontory, a characteristic position for the superior hypogastric plexus. - This plexus is involved in relaying **sympathetic innervation** to the pelvic viscera. *Ureter* - The ureter is a muscular tube that transports urine from the kidney to the bladder and is typically found running inferiorly and medially, often crossing the **common iliac vessels**. - Its appearance would be more tubular and less spread out than the depicted neural plexus. *Obturator nerve* - The obturator nerve arises from the **lumbar plexus** (L2-L4) and descends through the psoas major muscle, typically entering the lesser pelvis to supply the medial thigh compartment. - It would appear as a distinct nerve, not a broad plexus, and is usually found more laterally relative to **midline structures** in this view. *Genitofemoral nerve* - The genitofemoral nerve (L1, L2) pierces the **psoas major muscle** and soon splits into genital and femoral branches, running on the surface of the psoas. - Its slender, linear appearance and more lateral course differentiate it from the structure shown, which is a broader nerve network.
Question 320: Which is correct about the markings shown on the left popliteal fossa? (Recent NEET Pattern 2016-17)
- A. 1 = Tibial nerve, 2= popliteal vein, 3= popliteal artery, 4= Semitendinosus
- B. 1 = Popliteal artery, 2= popliteal vein, 3= tibial nerve, 4= Semitendinosus
- C. 1 = Tibial nerve, 2= popliteal vein, 3= popliteal artery, 4= Semimembranosus
- D. 1 = Popliteal artery, 2= popliteal vein, 3= tibial nerve, 4= Semimembranosus (Correct Answer)
Explanation: ***1 = Popliteal artery, 2= popliteal vein, 3= tibial nerve, 4= Semimembranosus*** - In the popliteal fossa, the **popliteal artery** is the deepest and most medial structure, followed by the **popliteal vein** and then the **tibial nerve** superficially. - The **semimembranosus** muscle forms part of the superomedial boundary of the popliteal fossa. *1 = Tibial nerve, 2= popliteal vein, 3= popliteal artery, 4= Semitendinosus* - This option incorrectly identifies the deepest structure as the tibial nerve and mislabels the superficial aspect of the neurovascular bundle. - The muscle labeled 4 is too broad and flat to be the semitendinosus, which is more slender and located superficial to the semimembranosus. *1 = Popliteal artery, 2= popliteal vein, 3= tibial nerve, 4= Semitendinosus* - While the first three structures are correctly identified in their relative positions, the muscle labeled 4 does not correspond to the **semitendinosus**. - The **semitendinosus** would be a more superficial and narrower muscle in this region. *1 = Tibial nerve, 2= popliteal vein, 3= popliteal artery, 4= Semimembranosus* - This option incorrectly identifies the **tibial nerve** as the deepest structure in the popliteal fossa. - The correct order from deep to superficial in the neurovascular bundle is artery, vein, then nerve.