Anatomical Variations and Anomalies

Anatomical Variations and Anomalies Indian Medical PG Question 1: Match the following 1. Hirschsprung's disease 2. Posterior urethral valve 3. Choledochal cyst 4. Intussusception A. Jaundice B. Currant jelly stools C. Distended abdomen D. Oligohydramnios

• A. 1-C, 2-D, 3-B, 4-A
• B. 1-A, 2-D, 3-B, 4-C
• C. 1-C, 2-D, 3-A, 4-B (Correct Answer)
• D. 1-D, 2-C, 3-A, 4-B

Anatomical Variations and Anomalies Explanation: ***Correct Answer: 1-C, 2-D, 3-A, 4-B*** **Correct Associations:** - **Hirschsprung's disease (1) → Distended abdomen (C)**: Congenital absence of ganglion cells in the distal bowel leads to functional obstruction and subsequent abdominal distension. This is a hallmark presentation in neonates and infants. - **Posterior urethral valve (2) → Oligohydramnios (D)**: Urethral obstruction in utero prevents normal fetal urine output, resulting in decreased amniotic fluid (oligohydramnios). This can be detected on prenatal ultrasound. - **Choledochal cyst (3) → Jaundice (A)**: Congenital dilatation of the bile ducts causes biliary obstruction, presenting with jaundice as part of the classic triad (jaundice, abdominal mass, and pain). - **Intussusception (4) → Currant jelly stools (B)**: Telescoping of bowel causes mucosal ischemia and venous congestion, leading to bloody mucoid stools with characteristic "currant jelly" appearance. This is a pathognomonic feature. *Incorrect: 1-C, 2-D, 3-B, 4-A* - Incorrectly associates choledochal cyst with currant jelly stools (which is specific to intussusception) and intussusception with jaundice (which indicates biliary pathology). *Incorrect: 1-A, 2-D, 3-B, 4-C* - Wrongly links Hirschsprung's disease with jaundice instead of its characteristic abdominal distension, and misidentifies intussusception's primary feature. *Incorrect: 1-D, 2-C, 3-A, 4-B* - Swaps the associations between Hirschsprung's disease and PUV. Oligohydramnios is specific to urinary tract obstruction (PUV), not intestinal pathology (Hirschsprung's).

Anatomical Variations and Anomalies Indian Medical PG Question 2: Which of the following is a treatment option for Volkmann's ischemia?

• A. Bone shortening
• B. Fasciotomy (Correct Answer)
• C. Cock up splint
• D. Turn buckle splint

Anatomical Variations and Anomalies Explanation: ***Fasciotomy*** - **Fasciotomy** is the **emergency surgical treatment** for **acute Volkmann's ischemia** caused by compartment syndrome. - This procedure involves making incisions through the fascia to relieve elevated compartment pressure and restore blood flow, preventing irreversible muscle and nerve damage. - Must be performed urgently to prevent progression to **Volkmann's contracture** (established muscle necrosis and fibrosis). *Bone shortening* - **Bone shortening** is a reconstructive procedure used in **late/established Volkmann's contracture**, not for acute ischemia. - It may be used to facilitate soft tissue reconstruction or correct deformities after muscle necrosis has occurred. - Does not address the acute ischemic emergency. *Cock up splint* - A **cock-up splint** maintains the wrist in extension and is used for **rehabilitation** in chronic/established Volkmann's contracture. - May help prevent further deformity or support weakened extensors after muscle damage has occurred. - Does not treat the acute compartment syndrome or restore blood flow. *Turn buckle splint* - A **turnbuckle splint** is used for **gradual correction of joint contractures** in established Volkmann's contracture. - This is a rehabilitative device for chronic cases, not for acute treatment. - Does not address the acute circulatory compromise or compartment syndrome.

Anatomical Variations and Anomalies Indian Medical PG Question 3: In an accident case, after the arrival of medical team, all should be done in early management except;

• A. Glasgow coma scale
• B. Check BP (Correct Answer)
• C. Stabilization of cervical vertebrae
• D. Check Respiration

Anatomical Variations and Anomalies Explanation: ***Check BP*** - In the **immediate/early management** of trauma (primary survey), while circulation assessment is crucial, the **initial assessment of circulation** focuses on: - **Pulse rate and quality** (radial, carotid) - **Capillary refill time** - **Skin color and temperature** - **Active hemorrhage control** - **Formal blood pressure measurement** with a cuff, while important, is typically recorded during or after these rapid initial assessments, as it takes more time to obtain an accurate reading. - In the context of this question, among the four options listed, BP measurement is relatively less immediate compared to the other life-saving priorities (airway protection, breathing assessment, C-spine stabilization, and GCS). - **Note:** This is a nuanced distinction - BP is assessed during primary survey, but the other three options have more immediate life-threatening implications if not addressed. *Glasgow coma scale* - **GCS assessment** is part of the **"D" (Disability)** step in the ATLS primary survey. - It is performed early to assess neurological status and level of consciousness. - GCS <8 indicates need for **definitive airway protection** (intubation). - This is a critical early assessment that guides immediate management decisions. *Stabilization of cervical vertebrae* - **C-spine immobilization** is part of the **"A" (Airway)** step - "Airway with cervical spine protection." - It is performed **simultaneously** with airway assessment using a **rigid cervical collar**. - This is the **first priority** in trauma management to prevent secondary spinal cord injury. - All trauma patients should be assumed to have C-spine injury until proven otherwise. *Check Respiration* - **Respiratory assessment** is part of the **"B" (Breathing)** step in the ATLS primary survey. - This involves checking: - **Respiratory rate and pattern** - **Chest wall movement** - **Air entry bilaterally** - **Signs of tension pneumothorax or flail chest** - This is an immediate life-saving priority and must be assessed early.

Anatomical Variations and Anomalies Indian Medical PG Question 4: Which of the following is not a component of the Thoracoscore?

• A. Surgery priorities
• B. ASA classifications
• C. Expected complications post-surgery (Correct Answer)
• D. Performance status

Anatomical Variations and Anomalies Explanation: ***Expected complications post-surgery*** - While patient risk assessment tools aim to predict surgical outcomes, the **Thoracoscore** specifically calculates risk based on present patient characteristics and surgical plan, not based on a list of expected complications. - Expected complications are a *result* of the risk score, not an input into its calculation. *ASA classifications* - The **American Society of Anesthesiologists (ASA) Physical Status Classification System** is a crucial component of the Thoracoscore, reflecting the patient's overall health status and comorbidity burden. - A higher ASA classification indicates greater surgical risk and contributes to the Thoracoscore calculation. *Surgery priorities* - **Surgery priority** (e.g., elective, urgent, emergency) is an important factor in the Thoracoscore, as urgent or emergent surgeries are associated with higher risk. - This parameter helps categorize the immediacy and complexity of the surgical intervention. *Performance status* - The patient's **performance status**, often assessed using scales like the Eastern Cooperative Oncology Group (ECOG) or Karnofsky, is a significant predictor of surgical outcome and is included in the Thoracoscore. - A lower performance status (indicating poorer functional capacity) increases the calculated surgical risk.

Anatomical Variations and Anomalies Indian Medical PG Question 5: Pressure difference of 5 mm Hg between the two upper limbs occurs in which congenital heart disease?

• A. HOCM
• B. Coarctation of Aorta
• C. Supra-valvular aortic stenosis (Correct Answer)
• D. TOF

Anatomical Variations and Anomalies Explanation: ***Supra-valvular aortic stenosis*** - **Supravalvular aortic stenosis** causes a **pressure gradient** across the aortic valve, leading to a significant **pressure difference** between the upper limbs, typically with a **higher pressure** in the right arm. - This is due to the **Coanda effect**, where the high-velocity jet of blood preferentially flows up the **right subclavian artery** as it exits the aorta. *HOCM (Hypertrophic Obstructive Cardiomyopathy)* - HOCM is characterized by hypertrophy of the **left ventricular septum** causing **outflow tract obstruction**, but it does not typically cause a significant **pressure difference** between the upper limbs. - The obstruction primarily affects **ventricular ejection** rather than differential flow to major arteries. *Coarctation of Aorta* - **Coarctation of the aorta** causes a significant **blood pressure difference** between the upper and lower extremities, with higher pressures in the arms [1]. - However, it does not typically cause a marked **pressure difference between the two upper limbs**, unless the coarctation is pre-ductal and affects the subclavian artery circulation asymmetrically, which is less common for a difference of just 5 mmHg. *TOF (Tetralogy of Fallot)* - **Tetralogy of Fallot** is a cyanotic heart disease involving **pulmonary stenosis**, ventricular septal defect, overriding aorta, and right ventricular hypertrophy [2]. - While it causes significant circulatory abnormalities and potential for **hypoxia**, it does not inherently lead to a measurable **pressure difference** between the upper limbs.

Anatomical Variations and Anomalies Indian Medical PG Question 6: The following arrow marked vessel can cause torrential hemorrhage during cholecystectomy. Which of the following is the correct description?

• A. Moynihan's caterpillar hump due to bend of right hepatic artery (Correct Answer)
• B. Moynihan's caterpillar hump due to bend of left hepatic artery
• C. Moynihan's caterpillar hump due to bend of cystic artery
• D. Moynihan's caterpillar hump due to bend of common hepatic artery

Anatomical Variations and Anomalies Explanation: ***Moynihan's caterpillar hump due to bend of right hepatic artery*** - The image shows an anatomical variation where the **right hepatic artery** forms a tortuous bend near the cystic duct, resembling a "caterpillar hump." - This anatomical anomaly, known as **Moynihan's hump**, places the right hepatic artery in close proximity to the operative field during cholecystectomy, making it vulnerable to accidental injury and potentially causing torrential hemorrhage. *Moynihan's caterpillar hump due to bend of left hepatic artery* - The left hepatic artery originates from the common hepatic artery and supplies the left lobe of the liver, typically staying well away from the area of concern during routine cholecystectomy. - A bend in the **left hepatic artery** would not be located in the position shown or pose the same risk during gallbladder removal. *Moynihan's caterpillar hump due to bend of cystic artery* - The cystic artery typically arises from the right hepatic artery and is ligated during cholecystectomy to devascularize the gallbladder. - While it supplies the gallbladder, the described "caterpillar hump" refers specifically to a tortuous **right hepatic artery**, not the cystic artery itself. *Moynihan's caterpillar hump due to bend of common hepatic artery* - The common hepatic artery branches into the proper hepatic artery and gastroduodenal artery, located more proximally to the area depicted. - A bend in the **common hepatic artery** would not be found in such close proximity to the cystic duct and would not be described as Moynihan's caterpillar hump in this context.

Anatomical Variations and Anomalies Indian Medical PG Question 7: All are derived from ectoderm except for which of the following?

• A. Hair follicles
• B. Nails
• C. Lens of the eye
• D. Adrenal cortex (Correct Answer)

Anatomical Variations and Anomalies Explanation: ***Adrenal cortex*** - The adrenal cortex is derived from the **intermediate mesoderm**, specifically from the cells lining the posterior abdominal wall. The cells migrate to develop into the adrenal cortex. - It produces various steroid hormones, including **aldosterone**, **cortisol**, and **androgens**, which regulate diverse bodily functions. *Lens of the eye* - The lens of the eye is derived from the **surface ectoderm**. It forms from an invagination of the surface ectoderm called the lens placode. - Its primary function is to **focus light** onto the retina. *Hair follicles* - Hair follicles develop from the **surface ectoderm** [1]; they are invaginations of the epidermis that extend into the dermis. - They produce hair, which provides **insulation** and **protection** [1]. *Nails* - Nails are also derivatives of the **surface ectoderm**, forming thickened plates on the dorsal surface of the distal phalanges. - They provide **protection** to the fingertips and aid in grasping objects.

Anatomical Variations and Anomalies Indian Medical PG Question 8: The following ocular structure is not derived from surface ectoderm –

• A. Epithelium of lacrimal glands
• B. Crystalline lens
• C. Sclera (Correct Answer)
• D. Corneal epithelium

Anatomical Variations and Anomalies Explanation: **Sclera** - The **sclera** develops from the **neural crest cells**, which differentiate into mesenchymal tissue around the optic cup, forming the fibrous coats of the eye [1]. - It is part of the **fibrous tunic** of the eye, along with the cornea, and provides structural support. *Epithelium of lacrimal glands* - The **epithelium of lacrimal glands** originates from the **surface ectoderm** through invaginations and subsequent differentiation. - These glands are responsible for producing the **watery component of tears**. *Crystalline lens* - The **crystalline lens** also develops from the **surface ectoderm**, specifically from the lens placode, which invaginates to form the lens vesicle. - It is crucial for **focusing light** onto the retina. *Corneal epithelium* - The **corneal epithelium** is derived from the **surface ectoderm** and forms the outermost layer of the cornea [1]. - It provides a **protective barrier** and helps maintain the smooth refractive surface of the cornea [1].

Anatomical Variations and Anomalies Indian Medical PG Question 9: Which of the following is TRUE about bronchopulmonary segments?

• A. Spherical in shape
• B. Artery is intersegmental
• C. Pulmonary veins are intersegmental (Correct Answer)
• D. Non resectable

Anatomical Variations and Anomalies Explanation: Detailed knowledge of lung anatomy is essential for thoracic surgery. ***Pulmonary veins are intersegmental*** - The **pulmonary veins** run in the connective tissue septa **between** the bronchopulmonary segments, making them **intersegmental** [1]. - This anatomical arrangement allows surgeons to ligate the veins without affecting adjacent segments during a segmentectomy. *Spherical in shape* - Bronchopulmonary segments are typically **pyramid-shaped** or cone-shaped, with their apices directed towards the hilum [1]. - Their irregular, wedge-like structure allows them to fit together within the lung. *Artery is intersegmental* - The **bronchial arteries** and **pulmonary arteries** are **intrasegmental**, meaning they run **within** the bronchopulmonary segment alongside the bronchi. - Each segment has its own arterial supply, allowing for independent blood flow. *Non resectable* - Bronchopulmonary segments are considered **functionally and surgically independent units**, making them **resectable** [1]. - This allows for the removal of diseased segments while preserving healthy lung tissue, such as in cases of **lung cancer** or localized infection.

Anatomical Variations and Anomalies Indian Medical PG Question 10: As shown in the figure, abnormal subclavian artery develops as a result of: (AIIMS May 2016)

• A. Persistence of B
• B. Persistence of A
• C. Obliteration of A with persistence of B
• D. Obliteration of B with persistence of A (Correct Answer)

Anatomical Variations and Anomalies Explanation: ***Obliteration of B with persistence of A*** - The image depicts the 7th intersegmental artery (labeled **A**) and the right dorsal aorta (labeled **B**). An **abnormal subclavian artery** (retroesophageal subclavian artery or arteria lusoria) results from the **obliteration of B** (the right dorsal aorta) distal to the 7th intersegmental artery (A). - When the right dorsal aorta (B) obliterates prematurely, the right subclavian artery (derived from A plus portions of the 4th aortic arch and right dorsal aorta) gets its distal blood supply from the left dorsal aorta, causing it to cross behind the esophagus to reach the right arm. *Persistence of B* - The normal development of the right subclavian artery involves the **regression** of a segment of the right dorsal aorta (part of **B**). If **B** (the right dorsal aorta) persists, it could lead to other malformations, but not typically an abnormal subclavian artery coursing behind the esophagus. - The persistence of the right dorsal aorta, usually proximal to the 7th intersegmental artery, would be part of a **double aortic arch** or other arch anomalies, rather than directly causing arteria lusoria. *Persistence of A* - **A** represents the **7th intersegmental artery**, which normally persists to form a crucial part of the subclavian artery. Persistence of **A** alone is a normal developmental event and does not lead to an abnormal subclavian artery. - An abnormal subclavian artery requires an alteration in the usual regression patterns of other embryological vessels, not merely the persistence of a normally persistent vessel. *Obliteration of A with persistence of B* - **Obliteration of A** (the 7th intersegmental artery) would prevent the formation of a normal subclavian artery altogether. This would lead to a severely underdeveloped or absent right subclavian artery, rather than one with an abnormal course. - If **A** obliterates, and **B** (right dorsal aorta) persists, the right arm would lack its primary arterial supply, which is a much more severe anomaly than a retroesophageal subclavian artery.

Anatomical Variations and Anomalies Flashcard 1 of 10

Question: The _____ is the most reliable bone for sex determination.

Answer: whole pelvis (bone)

Anatomical Variations and Anomalies Flashcard 2 of 10

Question: An occipital bone defect in a newborn with retroflexion of the neck and trunk is typical of _____.

Answer: iniencephaly

Anatomical Variations and Anomalies Flashcard 3 of 10

Question: _____ long bones have a modified shaft or ends, and no medullary cavity

Answer: Modified

Anatomical Variations and Anomalies Flashcard 4 of 10

Question: In the infantile form, coarctation of the aorta lies _____ the aortic arch, but before the PDA

Answer: after

Anatomical Variations and Anomalies Flashcard 5 of 10

Question: _____ skull is found in Europeans, Chinese, Indians

Answer: Mesaticephalic

Anatomical Variations and Anomalies Flashcard 6 of 10

Question: Orbits are round with sharp margins in a _____ skull

Answer: female

Anatomical Variations and Anomalies Flashcard 7 of 10

Question: Identify the type of hymen: _____

Answer: Cribriform

Anatomical Variations and Anomalies Flashcard 8 of 10

Question: Identify the type of hymen: _____

Answer: Septate

Anatomical Variations and Anomalies Flashcard 9 of 10

Question: _____ malformation presents as a massively dilated 4th ventricle and an absent cerebellar vermis

Answer: Dandy-Walker

Anatomical Variations and Anomalies Flashcard 10 of 10

Question: _____ and Parietal eminences are large in a female skull

Answer: Frontal