NEET-PG 2018 Practice Questions

Q: What constitutes the Malpighian layer of skin?

Spinosum and basale. The Malpighian layer is a historical term used to collectively refer to the stratum spinosum and stratum basale of the epidermis [1]. These two layers are responsible for keratinocyte proliferation (basale) and establishing strong intercellular connections via desmosomes (spinosum) [1].

Q: What is the primary function of the deltoid muscle?

Abduction of the shoulder. ***Abduction of the shoulder*** - The **deltoid muscle** is the major muscle responsible for **abducting the arm** at the shoulder joint, particularly after the initial 15-20 degrees. - Its different parts (anterior, middle, posterior) also contribute to flexion, extension, and rotation, but **abduction** is its primary and most powerful action. *Adduction of the shoulder* - **Adduction of the shoulder** involves moving the arm towards the midline of the body, which is primarily performed by muscles such as the **latissimus dorsi** and **pectoralis major**. - While some fibers of the deltoid can assist in adduction from certain positions, it is not its primary function. *Flexion of the elbow* - **Flexion of the elbow** involves bending the arm at the elbow joint and is primarily performed by muscles like the **biceps brachii**, **brachialis**, and **brachioradialis**. - The deltoid muscle is located at the shoulder and has no direct action on the elbow joint. *Extension of the wrist* - **Extension of the wrist** involves bending the hand backward at the wrist joint and is primarily performed by muscles in the forearm such as the **extensor carpi radialis** and **extensor digitorum**. - The deltoid muscle is a shoulder muscle and does not act on the wrist joint.

Q: Site for placing an electrode in auditory brain stem implant is?

Recess of fourth ventricle. ***Recess of fourth ventricle*** - The auditory brainstem implant (ABI) electrode arrays are typically placed on the surface of the **cochlear nucleus**, which lies in the **lateral recess of the fourth ventricle and cerebellopontine angle**. - This placement allows direct stimulation of the central auditory pathways, bypassing a damaged or absent auditory nerve. *Round window* - The round window is the site for electrode placement in a **cochlear implant**, not an auditory brainstem implant. - A cochlear implant stimulates the **auditory nerve terminals** within the cochlea. *Sinus tympani* - The sinus tympani is an **anatomical space** within the middle ear. - It is not a site for implant electrode placement for either cochlear or brainstem implants. *Lateral ventricle* - The lateral ventricles are spaces within the brain that contain **cerebrospinal fluid** and are not directly involved in the auditory pathway for implant stimulation. - Implants for hearing are generally directed towards the auditory neural structures.

Q: What is the characteristic smell of a properly mummified body?

Odourless. ***Odourless*** - A **properly mummified body** is characterized by **complete desiccation (drying) of tissues**, which prevents decomposition and eliminates putrefactive odors. - In **forensic contexts**, mummification typically occurs through **natural processes** in dry, well-ventilated environments, or through **artificial embalming** that removes moisture and inhibits bacterial growth. - The **absence of moisture** makes the body largely **odorless**, as decomposition bacteria cannot survive without water. *Sweet* - A **sweet smell** is associated with **early decomposition stages**, particularly due to the formation of **adipocere** (grave wax) or **ketone production** during fat breakdown. - This smell indicates **active decomposition**, which is **absent in properly mummified remains**. *Offensive* - An **offensive smell** indicates active **putrefaction** with significant microbial activity producing foul-smelling gases (hydrogen sulfide, cadaverine, putrescine). - Mummification **prevents putrefaction** by removing the moisture necessary for bacterial growth. - An offensive odor in supposed mummified remains suggests **incomplete mummification** or **environmental degradation**. *Pungent* - A **pungent smell** arises from **ammonia and volatile amines** produced during protein decomposition by bacteria. - This indicates **active autolysis and putrefaction**, processes that are **arrested in true mummification** due to tissue desiccation. - A properly preserved mummy should **not produce decomposition-related odors**.

Q: A patient has a history of RTA 2 years ago. He developed pain and swelling at the same site. What will be the diagnosis based on the provided X-ray features?

Chronic osteomyelitis. ***Chronic osteomyelitis*** - The history of an **RTA 2 years ago** suggests a prior injury or open fracture, which is a common predisposing factor for chronic osteomyelitis. - The X-ray shows changes consistent with chronic infection, such as **bony sclerosis**, **lytic areas** (abscesses/sequestration), and possibly **periosteal reaction**, indicating persistent inflammation and bone destruction. *Osteogenic sarcoma* - This is a **primary malignant bone tumor** typically presenting with aggressive periosteal reaction (**sunburst** or **Codman's triangle**) and rapid bone destruction, which are not the predominant features here. - While it can cause pain and swelling, the history of a remote RTA followed by a chronic course makes osteogenic sarcoma less likely than infection. *Ewing's sarcoma* - This is another **highly malignant bone tumor** known for its characteristic **onion-skin periosteal reaction** and lytic lesions, often presenting in younger individuals. - The X-ray features do not clearly depict the characteristic onion-skin appearance, and the temporal history suggests a chronic inflammatory process rather than an aggressive de novo tumor. *Multiple myeloma* - This is a **plasma cell malignancy** characterized by multiple punched-out lytic lesions in the bone, often affecting the axial skeleton. - The X-ray image shows a more localized and heterogeneous pattern of bone changes, including sclerosis and reactive bone formation, which are not typical for multiple myeloma.

Q: A patient had osteomyelitis in their left tibia 2 years ago. They now present with pain and swelling at the same site. X-ray shows bone destruction, sequestrum, and involucrum. What is the most likely diagnosis?

Chronic osteomyelitis. ***Chronic osteomyelitis*** - The presence of **bone destruction**, **sequestrum** (dead bone), and an **involucrum** (new bone formation around infected tissue) is pathognomonic for **chronic osteomyelitis**. - A history of prior osteomyelitis at the same site, followed by recurrent pain and swelling, indicates a **chronic, persistent infection**. *Ewing's sarcoma* - This is a **highly malignant primary bone tumor** that typically presents with a **"onion skin" appearance** on X-ray due to periosteal reaction, which is not described here. - While it causes pain and swelling, the specific radiological findings of sequestrum and involucrum are not characteristic of Ewing's sarcoma. *Osteogenic sarcoma* - Also known as **osteosarcoma**, this is a **primary bone malignancy** characterized by the production of **osteoid**. X-rays often show a **"sunburst" pattern** or Codman's triangle. - While it causes bone destruction and pain, the presence of sequestrum and involucrum points away from a primary bone tumor and towards a chronic infectious process. *Multiple myeloma* - This is a **hematologic malignancy** involving plasma cells, leading to **punched-out lytic lesions** in bones. - It does not typically present with sequestrum and involucrum, nor does it have a direct causal link to prior osteomyelitis in this manner.

Q: Which of the following is the most important infiltrate in rheumatoid arthritis?

Macrophages. ***Macrophages*** - **Macrophages** are crucial in rheumatoid arthritis synovium due to their role in producing **pro-inflammatory cytokines** like TNF-̑, IL-1, and IL-6, which drive joint destruction [1], [2]. - They also contribute to the **pannus formation** and degrade cartilage and bone through the release of proteases [1]. *Dendritic cells* - While present in the synovium, **dendritic cells primarily function as antigen-presenting cells**, initiating T-cell responses. - Their direct contribution to tissue damage and chronic inflammation is less prominent than that of macrophages. *CD4+ Helper cells* - **CD4+ T helper cells** orchestrate the immune response by activating B cells and macrophages, but they are not the primary effector cells causing direct tissue damage [3]. - They secrete cytokines that promote inflammation but do not directly participate in tissue degradation. *Neutrophils* - **Neutrophils are abundant in the synovial fluid** during acute flares, contributing to inflammation and breakdown of cartilage through the release of enzymes. - However, their role in the chronic, sustained synovial inflammation and tissue destruction characteristic of RA is less significant compared to macrophages. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Osteoarticular And Connective Tissue Disease, pp. 677-678. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Inflammation and Repair, pp. 105-106. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, p. 1212.

Q: What is the current term used to refer to Down syndrome?

Trisomy 21. ***Trisomy 21*** - This is the **current scientific and cytogenetic term** for Down syndrome, indicating the presence of an **extra copy of chromosome 21**. - It is the most accurate and precise term describing the **genetic basis** of the condition and is universally used in medical literature. - While "Down syndrome" remains the clinical name, **Trisomy 21** is the preferred term in genetic and diagnostic contexts. *Oligophrenia* - This is an **outdated and pejorative term** for intellectual disability, no longer used in medical or scientific contexts. - It was a general term for conditions with **significantly impaired intellectual development** but has been abandoned. *Mental retardation* - This term was historically used to describe conditions of cognitive impairment but has been **replaced by "intellectual disability"** due to its stigmatizing connotations. - It is **no longer acceptable** in modern medical terminology. *Intellectual disability* - This is the **current preferred term** for describing cognitive impairment, but it refers to the **functional consequence** of Down syndrome, not the condition itself. - While accurate for describing the cognitive aspects, **Trisomy 21** is the specific genetic diagnostic term. *Mongolism* - This is an **obsolete and offensive term** that was historically used for Down syndrome based on perceived facial features. - It has been completely **abandoned** due to its racist and pejorative nature and should never be used.

Q: What condition is shown in the MR angiogram of the skull?

Vein of Galen malformation. ***Vein of Galen malformation*** - The image provided is an **MR angiogram (MRA)**, which clearly shows a **large, dilated vein of Galen**. This is the characteristic appearance of a Vein of Galen malformation. - This congenital vascular malformation involves a direct artery-to-vein shunt, leading to the characteristic aneurysmal dilatation of the vein. *Dandy-Walker malformation* - This is a congenital brain malformation characterized by **agenesis or hypoplasia of the cerebellar vermis** and cystic dilation of the fourth ventricle. - While it affects brain structures, it does not involve the type of vascular abnormality seen in the image. *Pneumocephalus* - **Pneumocephalus** refers to the presence of **air within the intracranial cavity**, often due to trauma or surgery. - It would appear as dark areas on imaging, representing air, not the bright, dilated vascular structures seen here. *Crouzon syndrome* - **Crouzon syndrome** is a genetic disorder characterized by **craniosynostosis**, which is the premature fusion of skull sutures. - This condition primarily affects bone growth and skull shape, with no direct involvement of the cerebral vasculature as depicted in the MRA.

Question 1

What constitutes the Malpighian layer of skin?

Accepted Answer

Spinosum and basale

Answer

Corneum and lucidum

Answer

Spinosum only

Answer

Granulosum only

Question 2

What is the primary function of the deltoid muscle?

Accepted Answer

Abduction of the shoulder

Answer

Adduction of the shoulder

Answer

Flexion of the elbow

Answer

Extension of the wrist

Question 3

Site for placing an electrode in auditory brain stem implant is?

Accepted Answer

Recess of fourth ventricle

Answer

Round window

Answer

Sinus tympani

Answer

Lateral ventricle

Question 4

What is the characteristic smell of a properly mummified body?

Accepted Answer

Odourless

Answer

Sweet

Answer

Offensive

Answer

Pungent

Question 5

A patient has a history of RTA 2 years ago. He developed pain and swelling at the same site. What will be the diagnosis based on the provided X-ray features?

Accepted Answer

Chronic osteomyelitis

Answer

Osteogenic sarcoma

Answer

Ewing's sarcoma

Answer

Multiple myeloma

Question 6

A patient had osteomyelitis in their left tibia 2 years ago. They now present with pain and swelling at the same site. X-ray shows bone destruction, sequestrum, and involucrum. What is the most likely diagnosis?

Accepted Answer

Chronic osteomyelitis

Answer

Ewing's sarcoma

Answer

Osteogenic sarcoma

Answer

Multiple myeloma

Question 7

The following statement about keloid is true:

Accepted Answer

It will have more collagen and vascularity

Answer

Extended excision is the treatment of choice

Answer

Elevated levels of growth factor is not seen

Answer

They do not extend beyond the wound

Question 8

Which of the following is the most important infiltrate in rheumatoid arthritis?

Accepted Answer

Macrophages

Answer

Dendritic cells

Answer

CD4+ Helper cells

Answer

Neutrophils

Question 9

What is the current term used to refer to Down syndrome?

Accepted Answer

Trisomy 21

Answer

Oligophrenia

Answer

Mental retardation

Answer

Intellectual disability

Answer

Mongolism

Question 10

What condition is shown in the MR angiogram of the skull?

Accepted Answer

Vein of Galen malformation

Answer

Dandy-Walker malformation

Answer

Pneumocephalus

Answer

Crouzon syndrome

NEET-PG 2018

Anatomy

ENT

Forensic Medicine

Orthopaedics

Pathology

Psychiatry

Radiology