Congenital Hand Anomalies — MCQs
Tardy ulnar nerve palsy is specifically associated with which type of fracture?
Hand deformity presenting as hyperextension at the metacarpophalangeal joint and flexion at the interphalangeal joint occurs due to paralysis of which muscle group?
In which of the following conditions is an atrial septal defect (ASD) commonly observed?
In which condition is the presence of an extra pair of ribs sometimes observed?
What type of epiphysis is represented by the epiphysis at the tip of the coracoid process?
Madelung's deformity is characterized by an abnormality in which bone?
What is the most common route of transmission for Toxoplasma gondii in adults?
Identify the condition shown in the CT scan image.
Which one of the following life-threatening congenital anomalies in the newborn presents with polyhydramnios, aspiration pneumonia, excessive salivation and difficulty in passing a nasogastric tube?
Fracture at which site affects the longitudinal growth of a bone?
Congenital Hand Anomalies Indian Medical PG Practice Questions and MCQs
Question 1: Tardy ulnar nerve palsy is specifically associated with which type of fracture?
- A. Lateral condyle fracture of the humerus (Correct Answer)
- B. Medial condyle fracture of the humerus
- C. Fracture of the humeral shaft
- D. Fracture of the radial shaft
Explanation: ***Lateral condyle fracture of the humerus*** - This fracture, especially in children, can lead to **cubitus valgus deformity** as a long-term complication if it heals incorrectly. - The resulting **valgus angulation** at the elbow abnormally stretches the ulnar nerve behind the medial epicondyle, causing **tardy ulnar nerve palsy** years after the initial injury. *Medial condyle fracture of the humerus* - While close to the ulnar nerve, medial condyle fractures are more likely to cause **immediate nerve damage** due to direct impingement, rather than delayed or "tardy" palsy from chronic stretching. - Complications typically involve varus deformity, which does not commonly stretch the ulnar nerve in the same manner as valgus. *Fracture of the humeral shaft* - This type of fracture is more commonly associated with **radial nerve injury** (e.g., wrist drop), especially in fractures of the mid-shaft. - It does not typically lead to long-term deformities at the elbow that would cause **delayed ulnar nerve compression**. *Fracture of the radial shaft* - Radial shaft fractures (e.g., Monteggia, Galeazzi) primarily affect the **radial nerve** or the **posterior interosseous nerve**. - They do not directly involve the elbow joint in a manner that would cause **tardy ulnar nerve palsy**.
Question 2: Hand deformity presenting as hyperextension at the metacarpophalangeal joint and flexion at the interphalangeal joint occurs due to paralysis of which muscle group?
- A. Extensor digitorum
- B. Lumbricals and interossei (Correct Answer)
- C. Flexor digitorum profundus
- D. Intrinsic hand muscles excluding interossei
Explanation: ***Lumbricals and interossei*** - This deformity, also known as a **claw hand**, results from the paralysis of the **lumbricals** and **interossei** muscles, which are crucial for flexing the **metacarpophalangeal (MCP)** joints and extending the **interphalangeal (IP)** joints [1]. - When these muscles are paralyzed, the unopposed action of the **extensor digitorum** causes **MCP joint hyperextension**, and the unopposed action of the **flexor digitorum superficialis** and **profundus** causes **IP joint flexion**. *Extensor digitorum* - The **extensor digitorum** primarily extends the **MCP** and **IP** joints; its paralysis would lead to **flexion deformities**, not hyperextension at the MCP joint. - Paralysis of the intrinsic muscles removes the counteracting force that limits **extensor digitorum** action at the **MCP joints**, leading to their hyperextension. *Flexor digitorum profundus* - The **flexor digitorum profundus** primarily flexes the **distal interphalangeal (DIP)** joints [1]. Its paralysis would result in an inability to flex these joints, not the described deformity. - This muscle contributes to the IP flexion seen in claw hand when unbalanced by weak intrinsic muscles, but its paralysis alone would not cause this specific pattern. *Intrinsic hand muscles excluding interossei* - This option is too broad and vague. While some intrinsic muscles (e.g., thenar or hypothenar muscles) contribute to hand function, the specific combination of **lumbricals** and **interossei** is responsible for the classic claw hand deformity. - The **lumbricals** and **interossei** are the key intrinsic muscles for the balance of forces at the MCP and IP joints; excluding interossei would leave out a critical component of the deformity's cause [1].
Question 3: In which of the following conditions is an atrial septal defect (ASD) commonly observed?
- A. Down syndrome
- B. Turner's syndrome
- C. Holt-Oram syndrome (Correct Answer)
- D. Ellis-van Creveld syndrome
Explanation: ***Correct: Holt-Oram syndrome*** - Holt-Oram syndrome has the **strongest and most specific association with secundum atrial septal defects (ASDs)** among the options listed - Approximately **75% of patients have congenital heart defects**, with **ASD being the most common** (followed by VSD) - Classic presentation: **upper limb abnormalities** (radial ray defects, triphalangeal thumb) + **ASD** - Autosomal dominant inheritance with mutations in TBX5 gene - When a question asks about "commonly observed" ASD, Holt-Oram is the classic teaching association *Incorrect: Ellis-van Creveld syndrome* - While Ellis-van Creveld syndrome does have a high incidence of cardiac defects (50-60%), the **most characteristic cardiac finding is a common atrium (single atrium)** rather than a typical secundum ASD - A common atrium is an extreme form of ASD where there is complete absence of the atrial septum - The syndrome is primarily characterized by **chondroectodermal dysplasia**: short limbs, short ribs, polydactyly, and dental/nail abnormalities - Much rarer than Holt-Oram syndrome *Incorrect: Down syndrome* - Down syndrome (Trisomy 21) has a high prevalence of congenital heart defects (40-50%), but the **most characteristic defect is an atrioventricular septal defect (AVSD)**, also known as endocardial cushion defect - While AVSDs involve the atrial septum, they are **distinct from isolated ASDs** and involve both the atrial and ventricular septa with abnormal AV valves - Other common defects: VSD, PDA, and tetralogy of Fallot *Incorrect: Turner's syndrome* - Turner's syndrome (45,XO) is characterized by congenital heart defects in about 25-50% of cases - The **most common cardiac abnormalities are coarctation of the aorta (30%) and bicuspid aortic valve (30%)** - Left-sided obstructive lesions predominate; **ASDs are less commonly associated** with Turner's syndrome - Other features: short stature, webbed neck, lymphedema, and gonadal dysgenesis
Question 4: In which condition is the presence of an extra pair of ribs sometimes observed?
- A. Down syndrome
- B. Turner syndrome (Correct Answer)
- C. Holt-Oram syndrome
- D. Fibrous dysplasia
- E. Klinefelter syndrome
Explanation: ***Turner syndrome*** - **Turner syndrome** (45,X) is often associated with skeletal abnormalities, including an extra pair of ribs (cervical ribs) in some cases. - Other common skeletal features include **short stature**, a **shield chest**, and **cubitus valgus**. *Down syndrome* - **Down syndrome** (trisomy 21) is characterized by specific facial features, intellectual disability, and congenital heart defects. - While it can manifest with various skeletal anomalies, an extra pair of ribs is not a characteristic feature. *Klinefelter syndrome* - **Klinefelter syndrome** (47,XXY) is characterized by hypogonadism, tall stature, gynecomastia, and learning difficulties. - Skeletal features may include long limbs and decreased bone density, but cervical ribs are not typically associated with this condition. *Holt-Oram syndrome* - **Holt-Oram syndrome** is a genetic disorder affecting heart and limb development, specifically the upper limbs (thumb abnormalities, phocomelia). - It does not typically involve the presence of an extra pair of ribs. *Fibrous dysplasia* - **Fibrous dysplasia** is a bone disorder where normal bone is replaced by fibrous tissue, leading to weakened bone and fractures. - It is a localized bone condition and does not involve the presence of supernumerary ribs.
Question 5: What type of epiphysis is represented by the epiphysis at the tip of the coracoid process?
- A. Atavistic (Correct Answer)
- B. Traction epiphysis
- C. Pressure epiphysis
- D. None of the options
Explanation: ***Atavistic*** - An **atavistic epiphysis** is a phylogenetic remnant representing a part that was a **separate bone in lower vertebrates** but has become fused in humans during evolution. - The **tip of the coracoid process** is classified as an atavistic epiphysis because the coracoid was a separate bone in reptiles and birds, and the apical epiphysis at its tip represents this evolutionary remnant. - This epiphysis appears around **puberty (15-18 years)** and fuses by the **mid-twenties** [1]. [1] *Traction epiphysis* - A **traction epiphysis** is located at sites of **major muscle or tendon attachment** and does not contribute to longitudinal bone growth. - While the coracoid process does have a traction epiphysis at its **base** (for attachments of short head of biceps and coracobrachialis), the question specifically asks about the **tip/apex** of the coracoid process. - The **tip** primarily represents a phylogenetic remnant rather than serving as the primary attachment point, making it atavistic rather than traction in classification. *Pressure epiphysis* - A **pressure epiphysis** is found at the **articular ends of long bones**, transmits weight-bearing forces, and contributes significantly to **longitudinal bone growth** [1]. - The coracoid process tip is a non-articular projection that does not bear weight or transmit pressure across joints. - It does not contribute to longitudinal growth of the scapula [1]. *None of the options* - This option is incorrect because the tip of the coracoid process definitively fits the classification of an **atavistic epiphysis** based on its evolutionary origin and developmental characteristics.
Question 6: Madelung's deformity is characterized by an abnormality in which bone?
- A. Humerus
- B. Proximal ulna
- C. Distal radius (Correct Answer)
- D. Carpals
Explanation: ***Distal radius*** - **Madelung's deformity** is primarily characterized by a **malformation of the distal radius**, specifically the physis (growth plate). - This leads to abnormal growth, causing the **radius to shorten and bow** dorsally, resulting in a prominent distal ulna. *Humerus* - The **humerus** is the bone of the upper arm, and abnormalities of this bone are not characteristic of Madelung's deformity. - Conditions affecting the humerus typically involve the shoulder or elbow joint, distinct from the wrist pathology seen in Madelung's. *Proximal ulna* - The **proximal ulna** forms part of the elbow joint, and while the ulna can be affected, the primary abnormality in Madelung's is in the radius. - While the ulna may appear prominent, this is secondary to the radial deformity, not a primary issue of the proximal ulna. *Carpals* - The **carpal bones** are located in the wrist, distal to the radius and ulna, and are not the primary site of deformity in Madelung's. - While wrist motion may be affected, the underlying cause is the abnormal growth of the distal radius, which can then impact carpal alignment.
Question 7: What is the most common route of transmission for Toxoplasma gondii in adults?
- A. Transmission through blood transfusion
- B. Ingestion of undercooked meat containing tissue cysts (Correct Answer)
- C. Congenital transmission from mother to fetus
- D. Fecal-oral transmission via contaminated cat feces
Explanation: ***Ingestion of undercooked meat containing tissue cysts*** - Consuming **undercooked or raw meat** (especially pork and lamb) containing **tissue cysts (bradyzoites)** is the **most common route** of *Toxoplasma gondii* transmission in adults in most countries - These cysts are highly resistant and survive digestion, releasing bradyzoites that cause systemic infection - This accounts for **30-63%** of infections in various populations *Fecal-oral transmission via contaminated cat feces* - Contact with **oocysts** from cat feces (in litter boxes, contaminated soil/water) is an important route - However, it's less common than meat consumption in most developed countries - Oocysts require 1-5 days to sporulate and become infective *Transmission through blood transfusion* - **Rare route** - tachyzoites have short survival in stored blood - Modern screening practices have made this extremely uncommon - Not a significant transmission route in general populations *Congenital transmission from mother to fetus* - Occurs when **primary maternal infection** happens during pregnancy - Important clinically but represents a small proportion of total infections - Does not apply to adult acquisition of infection
Question 8: Identify the condition shown in the CT scan image.
- A. None of the options
- B. Dandy-Walker malformation (Correct Answer)
- C. Cerebellar vermis hypoplasia
- D. Mega cisterna magna
Explanation: ***Dandy-Walker malformation*** - The image shows an enlarged posterior fossa with **cystic dilation of the fourth ventricle** and **absence/hypoplasia of the cerebellar vermis**, which are classic features of Dandy-Walker malformation. - The elevated tentorium and upward displacement of the transverse sinuses are also characteristic, contributing to the distinct appearance. *Cerebellar vermis hypoplasia* - While cerebellar vermis hypoplasia is a component of Dandy-Walker malformation, it is not the sole, defining feature. - Dandy-Walker also includes cystic dilation of the fourth ventricle and an enlarged posterior fossa, which are evident in the image and go beyond isolated vermis hypoplasia. *Mega cisterna magna* - A **mega cisterna magna** is a benign enlargement of the cisterna magna, which is the space between the cerebellum and the medulla oblongata. - Unlike in Dandy-Walker malformation, a mega cisterna magna usually does not involve displacement of the tentorium or hypoplasia of the cerebellar vermis, and the fourth ventricle is typically normal in shape and size. *None of the options* - The image clearly displays the diagnostic hallmarks of Dandy-Walker malformation, making this option incorrect.
Question 9: Which one of the following life-threatening congenital anomalies in the newborn presents with polyhydramnios, aspiration pneumonia, excessive salivation and difficulty in passing a nasogastric tube?
- A. Choanal atresia
- B. Gastroschisis
- C. Diaphragmatic hernia
- D. Tracheo-esophageal fistula (Correct Answer)
Explanation: ***Tracheo-esophageal fistula*** - This condition presents with **polyhydramnios** due to the fetus being unable to swallow amniotic fluid, **excessive salivation** from accumulated secretions in the blind-ending esophageal pouch, and difficulty passing a **nasogastric tube** because of the esophageal obstruction. - **Aspiration pneumonia** is a common complication as saliva and gastric contents can be aspirated into the lungs through the fistula. *Choanal atresia* - Characterized by **blocked nasal passages**, leading to **cyclical cyanosis** relieved by crying, but not typically associated with polyhydramnios or excessive salivation in this manner. - While it can cause respiratory distress, it does not involve esophageal obstruction or directly cause aspiration pneumonia from swallowed fluids. *Gastroschisis* - This is an **abdominal wall defect** where intestines protrude outside the body, unrelated to swallowing difficulties, polyhydramnios caused by inability to swallow, or excessive salivation. - It does not involve difficulty in passing a nasogastric tube or directly cause aspiration pneumonia. *Diaphragmatic hernia* - Involves **abdominal contents herniating into the chest cavity**, leading to **pulmonary hypoplasia** and respiratory distress. - It does not explain polyhydramnios due to impaired swallowing, excessive salivation, or the characteristic inability to pass a nasogastric tube.
Question 10: Fracture at which site affects the longitudinal growth of a bone?
- A. Epiphyseal plate (Correct Answer)
- B. Diaphysis
- C. Epiphysis
- D. Metaphysis
Explanation: ***Epiphyseal plate*** - The **epiphyseal plate**, also known as the **growth plate**, is a cartilaginous disc responsible for the **longitudinal growth** of long bones. - A fracture in this region can damage the **chondrocytes** and disrupt the normal ossification process, potentially leading to **growth arrest** or limb length discrepancies. *Diaphysis* - The **diaphysis** is the **shaft** or central part of a long bone. - While a fracture here can cause pain and instability, it typically does not directly affect the **longitudinal growth** potential of the bone. *Epiphysis* - The **epiphysis** is the end part of a long bone, initially separated from the main bone by cartilage but later fused with it. - Although it contains the epiphyseal plate in growing individuals, a fracture to the epiphysis itself (excluding the growth plate) primarily affects the **joint surface** and stability, rather than longitudinal growth directly. *Metaphysis* - The **metaphysis** is the transitional zone between the diaphysis and the epiphysis, adjacent to the growth plate. - While fractures in this area can be close to the growth plate, a metaphyseal fracture generally does not directly damage the **growth plate cartilage** to the same extent as a fracture through the plate itself, making its impact on longitudinal growth less direct or severe.
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free