NEET-PG 2024 Practice Questions

Q: The covering of an omphalocele is derived from which of the following layers?

Amnion. ***Amnion*** - An **omphalocele** is a congenital abdominal wall defect where abdominal contents protrude through the umbilical ring, covered by a sac derived from the **amnion** and peritoneum. - The covering of an omphalocele defect is an intact peritoneal sac that is covered externally by **amnion**. *Chorion* - The **chorion** is the outermost membrane surrounding an embryo, providing protection and nourishment, but it does not form the covering of an omphalocele. - It works in conjunction with the decidua to form the **placenta** and has finger-like projections called villi on its outer surface. *Mesoderm* - The **mesoderm** is one of the three primary germ layers in embryonic development, giving rise to connective tissue, muscle, and blood cells. - **Fetal skin**, not the omphalocele covering, develops from the mesoderm and ectoderm. *Endoderm* - The **endoderm** is the innermost of the three primary germ layers, giving rise to the lining of the digestive tract and respiratory system. - The omphalocele covering is derived from the amnion, not the endoderm, which is involved in forming internal organs. *Ectoderm* - The **ectoderm** is the outermost of the three primary germ layers, giving rise to the nervous system, skin epidermis, and sensory organs. - While ectoderm contributes to skin development, the omphalocele sac is specifically covered by amnion, not ectodermal derivatives.

Q: A patient presents with pain in the back of the thigh and leg after lifting heavy weights. Which spinal segment is most likely involved?

S1. ***S1*** - Pain radiating to the **back of the thigh and leg** after lifting heavy weights is the classic presentation of **S1 radiculopathy**, typically from L5-S1 disc herniation. - The S1 nerve root innervates the **posterior thigh via the sciatic nerve**, continues down the **posterior leg**, and extends to the **lateral foot and little toe**. - Clinical findings include diminished or absent **Achilles reflex**, weakness of **plantar flexion** (gastrocnemius/soleus), and sensory changes along the posterior leg and lateral foot. - This is the **most common** presentation of sciatica from heavy lifting. *L3* - L3 nerve root involvement typically causes pain in the **anterior and medial thigh** with weakness of **hip flexion and knee extension** (quadriceps). - The pain pattern does not match the posterior distribution described in this clinical scenario. *L4* - L4 radiculopathy presents with pain and numbness in the **medial leg and foot**, weakness of **ankle dorsiflexion** (tibialis anterior), and diminished **patellar reflex**. - The pain distribution is anteromedial, not posterior as described in this case. *L5* - L5 nerve root impingement causes pain radiating to the **lateral calf and dorsum of the foot**, weakness of **great toe extension** (extensor hallucis longus), and **foot drop**. - While L5 can cause posterior thigh pain, the classic distribution extends laterally down the leg, not primarily posterior. *S2* - S2 radiculopathy is uncommon and typically presents with **perineal/perianal pain** and **saddle anesthesia** rather than isolated posterior leg pain. - S2 contributes to bladder and bowel function; isolated S2 involvement would not present with the classic sciatica pattern described.

Q: Which artery is palpated behind the medial malleolus and in front of the Achilles tendon?

Posterior tibial artery. ***Posterior tibial artery*** - This artery is directly accessible for palpation in the **retromalleolar groove**, situated between the medial malleolus and the Achilles tendon. - It is a common site for assessing **peripheral circulation** in the foot. *Peroneal artery* - The peroneal artery is located **deep within the posterior compartment** of the leg, making it difficult to palpate at the ankle. - It primarily supplies the lateral compartment and is not typically palpable at the described location. *Anterior tibial artery* - The anterior tibial artery runs along the **anterior compartment** of the lower leg and, at the ankle, becomes the dorsalis pedis artery. - It is best palpated on the **dorsum of the foot** as the dorsalis pedis artery, not behind the medial malleolus. *Dorsalis pedis artery* - This artery is a continuation of the anterior tibial artery and is found on the **dorsum of the foot**, typically lateral to the extensor hallucis longus tendon. - While an important pulse point, it is not located behind the medial malleolus. *Popliteal artery* - The popliteal artery is located in the **popliteal fossa** behind the knee, where it can be palpated with deep pressure. - It is proximal to the ankle and divides into the anterior and posterior tibial arteries, making it anatomically distant from the medial malleolus.

Q: A patient diagnosed with sciatica has tender hamstrings. Which of the following nerves supplies a hybrid muscle that is partially spared in this patient?

Common peroneal nerve. ***Common peroneal nerve*** - The **short head of the biceps femoris** is a unique "hybrid" muscle, supplied by the **common peroneal nerve**, while the **long head** is supplied by the **tibial nerve**. - If the hamstrings are tender and sciatica is present, but this specific muscle's function is spared, it points towards the common peroneal nerve being the relevant nerve for the spared portion. *Femoral* - The **femoral nerve** primarily innervates the **anterior compartment of the thigh**, including the quadriceps femoris. - It does not supply any part of the hamstring muscles. *Obturator* - The **obturator nerve** primarily innervates the **medial compartment of the thigh**, which consists of adductor muscles. - It does not contribute to the innervation of the hamstring muscles. *Superior gluteal* - The **superior gluteal nerve** innervates the **gluteus medius**, **gluteus minimus**, and **tensor fasciae latae** muscles. - It does not supply any hamstring muscles. *Tibial* - The **tibial nerve** innervates most of the hamstring muscles (semitendinosus, semimembranosus, and the long head of the biceps femoris). - If the hamstrings are tender, involvement of the tibial nerve would likely lead to more widespread hamstring weakness rather than a partially spared scenario involving the short head of the biceps femoris.

Q: What is the most common site of congenital diaphragmatic hernia?

Posterolateral. ***Posterolateral*** - The **posterolateral** region, specifically the foramen of Bochdalek, is the most common site for congenital diaphragmatic hernia (CDH). - This type of hernia accounts for approximately 80-90% of all CDH cases and usually occurs on the **left side**. *Central tendon* - Hernias through the **central tendon** are extremely rare and are distinct from the more common forms of CDH. - Defects in the central tendon are often associated with **pericardial defects** rather than typical diaphragmatic hernias which allow abdominal contents into the thoracic cavity. *Crural* - Hernias involving the **crura** of the diaphragm are typically **hiatal hernias** (e.g., sliding or paraesophageal), which are different in origin and presentation from CDH. - These are usually acquired and involve the stomach moving into the mediastinum, rather than a congenital defect leading to abdominal viscera migrating into the chest. *Anterolateral* - While congenital diaphragmatic hernias can occur **anterolaterally** through the foramen of Morgagni, these are much less common than posterolateral hernias. - Morgagni hernias account for a small percentage of CDH cases (around 2-5%) and are typically located on the right side, often containing omentum or colon. *Esophageal hiatus* - The **esophageal hiatus** is the normal opening in the diaphragm through which the esophagus passes. - While hiatal hernias can occur at this site, these are typically **acquired hernias** in adults, not congenital diaphragmatic hernias. - Congenital CDH refers to developmental defects in the diaphragm itself, not enlargement of normal openings.

Q: A patient presents with loss of sensation on the lateral 3½ fingers and thenar atrophy. Which nerve is most likely involved?

Median. ***Median*** - The **median nerve** provides sensation to the **lateral 3½ fingers** (thumb, index, middle, and radial half of the ring finger) and innervates the **thenar muscles**, making its involvement consistent with the described symptoms [1]. - **Thenar atrophy** points directly to motor innervation loss of the thenar eminence, which is a key function of the median nerve. *Ulnar* - The **ulnar nerve** supplies sensation to the **medial 1½ fingers** (little finger and ulnar half of the ring finger) and innervates most of the **intrinsic hand muscles**, but not the thenar muscles [1]. - Damage typically causes **hypothenar atrophy** and **clawing** of the 4th and 5th digits, which are not described here. *Radial* - The **radial nerve** primarily provides sensation to the **dorsal aspect of the hand** and innervates the **extensor muscles of the forearm and hand**. - Its injury would typically lead to **wrist drop** and sensory loss in the dorsal hand, not thenar atrophy or lateral finger sensory loss. *Anterior interosseous nerve* - The **anterior interosseous nerve** is a **purely motor branch of the median nerve** that innervates muscles involved in **flexion of the thumb IP joint** and **index finger DIP joint**. - It does not have any sensory innervation, so loss of sensation in the lateral 3½ fingers would not be a symptom.

Q: What is the diagnosis based on the image shown ![img-5.jpeg](img-5.jpeg)

Bladder exstrophy. ***Bladder exstrophy*** - The image distinctly shows an **exposed urinary bladder** on the abdominal wall, a hallmark of bladder exstrophy. - This congenital anomaly results from a **failure of midline closure** of the infraumbilical abdominal wall and bladder. *Omphalocele* - An omphalocele involves protrusion of **abdominal viscera** (intestines, liver) into the base of the umbilical cord. - The herniated organs are typically **covered by a sac** composed of peritoneum and amnion, which is absent in the image. *Umbilical hernia* - An umbilical hernia is a protrusion of abdominal contents through the **umbilical ring**, but the skin remains intact and covers the defect. - The image clearly shows an **exposed organ** without skin coverage, ruling out an umbilical hernia. *Gastroschisis* - Gastroschisis involves the **evisceration of intestines** through a full-thickness abdominal wall defect, usually to the right of the umbilical cord. - Unlike the image, the defect in gastroschisis is typically **much smaller** and primarily involves the bowel, not the bladder, and there is no covering sac. *Epispadias* - Epispadias is a **urethral defect** where the urethral opening is on the dorsal (upper) surface of the penis or anterior bladder neck. - While epispadias is part of the **exstrophy-epispadias complex** and often associated with bladder exstrophy, it does not present with an **exposed bladder** on the abdominal wall as seen in the image.

Q: What are the effects of a lesion in Brodmann area 22?

Receptive aphasia. ***Receptive aphasia*** - A lesion in **Brodmann area 22**, specifically in **Wernicke's area**, leads to **receptive aphasia** (Wernicke's aphasia). - This condition is characterized by **impaired comprehension** of spoken and written language, **fluent but paraphasic speech**, and **poor repetition**. - This is the most comprehensive answer as it describes the entire clinical syndrome. *Expressive aphasia* - **Brodmann areas 44 and 45** (Broca's area) in the frontal lobe are associated with expressive aphasia (Broca's aphasia). - Patients have good comprehension but struggle to produce fluent speech, with effortful, telegraphic output. *Poor repetition of language* - While poor repetition is indeed a feature of Wernicke's aphasia, this option describes only one component of the syndrome rather than the complete clinical picture. - **Conduction aphasia** (from arcuate fasciculus lesions) is characterized by poor repetition with **relatively preserved** comprehension and fluent speech, distinguishing it from Wernicke's aphasia. - "Receptive aphasia" is the more complete answer. *Poor naming* - Difficulty with naming, or **anomia**, is a common feature across various types of aphasia, including both receptive and expressive aphasia. - It reflects disruption in language networks involving the **temporal and parietal lobes** but is not specific to Brodmann area 22 lesions.

Q: A patient presents with fecal discharge from the umbilicus. What is the most likely diagnosis?

Patent vitelline duct. ***Patent vitelline duct*** - **Fecal discharge from the umbilicus** indicates a persistent communication between the **ileum** and the **umbilicus** through a patent vitelline (omphalomesenteric) duct. - This congenital anomaly represents a remnant of the **omphalomesenteric duct** that **completely failed to involute**, creating a **fistulous tract** allowing intestinal contents to exit through the umbilicus. - This is the **most complete form** of vitelline duct persistence (other forms include Meckel's diverticulum, fibrous band, or umbilical polyp). *Urachal fistula* - A urachal fistula occurs when the **urachus** remains patent, creating a connection between the **bladder** and the umbilicus. - While it can result in umbilical discharge, the discharge would be **urine**, not feces. *Omphalocele* - An omphalocele is a **congenital abdominal wall defect** where abdominal contents protrude into a sac at the base of the umbilicus. - It does not involve a fistulous communication with intestines causing fecal discharge, but rather a **herniation** of organs covered by a peritoneal membrane. *Gastroschisis* - Gastroschisis is a congenital anomaly characterized by the **protrusion of abdominal organs** directly into the amniotic cavity **without a covering sac**, usually to the **right of the umbilicus**. - Like omphalocele, it's a **herniation defect** presenting at birth and does not involve an abnormal fistulous connection causing fecal discharge from the umbilicus.

Question 1

The covering of an omphalocele is derived from which of the following layers?

Accepted Answer

Amnion

Answer

Chorion

Answer

Mesoderm

Answer

Endoderm

Answer

Ectoderm

Question 2

A patient presents with pain in the back of the thigh and leg after lifting heavy weights. Which spinal segment is most likely involved?

Accepted Answer

S1

Answer

L4

Answer

L5

Answer

S2

Answer

L3

Question 3

Which artery is palpated behind the medial malleolus and in front of the Achilles tendon?

Accepted Answer

Posterior tibial artery

Answer

Peroneal artery

Answer

Anterior tibial artery

Answer

Dorsalis pedis artery

Answer

Popliteal artery

Question 4

Match the following nerves to their respective areas of supply to the auricle

Accepted Answer

A - Auriculotemporal, B - Greater auricular, C - Vagus, D - Lesser occipital

Answer

A - Greater auricular, B - Auriculotemporal, C - Lesser occipital, D - Vagus

Answer

A - Auriculotemporal, B - Lesser occipital, C - Greater auricular, D - Vagus

Answer

A - Auriculotemporal, B - Lesser occipital, C - Vagus, D - Greater auricular

Answer

A - Vagus, B - Greater auricular, C - Auriculotemporal, D - Lesser occipital

Question 5

A patient diagnosed with sciatica has tender hamstrings. Which of the following nerves supplies a hybrid muscle that is partially spared in this patient?

Accepted Answer

Common peroneal nerve

Answer

Femoral

Answer

Obturator

Answer

Tibial

Answer

Superior gluteal

Question 6

What is the most common site of congenital diaphragmatic hernia?

Accepted Answer

Posterolateral

Answer

Central tendon

Answer

Crural

Answer

Anterolateral

Answer

Esophageal hiatus

Question 7

A patient presents with loss of sensation on the lateral 3½ fingers and thenar atrophy. Which nerve is most likely involved?

Accepted Answer

Median

Answer

Ulnar

Answer

Radial

Answer

Anterior interosseous nerve

Question 8

What is the diagnosis based on the image shown
![img-5.jpeg](img-5.jpeg)

Accepted Answer

Bladder exstrophy

Answer

Omphalocele

Answer

Umbilical hernia

Answer

Gastroschisis

Answer

Epispadias

Question 9

What are the effects of a lesion in Brodmann area 22?

Accepted Answer

Receptive aphasia

Answer

Expressive aphasia

Answer

Poor repetition of language

Answer

Poor naming

Question 10

A patient presents with fecal discharge from the umbilicus. What is the most likely diagnosis?

Accepted Answer

Patent vitelline duct

Answer

Urachal fistula

Answer

Omphalocele

Answer

Gastroschisis

NEET-PG 2024

Anatomy

Pediatrics

Physiology

Surgery