Pediatric Orthopaedics — MCQs

Pediatric Orthopaedics Indian Medical PG Practice Questions and MCQs

Question 81: What is the commonest congenital deformity?

A. Congenital club hand
B. Congenital club foot (Correct Answer)
C. Absence of femur
D. Absence of fibula

Explanation: **Explanation:** **Congenital Clubfoot (CTEV - Congenital Talipes Equinovarus)** is the most common congenital musculoskeletal deformity, occurring in approximately 1 to 2 per 1,000 live births. It is characterized by a complex three-dimensional deformity involving four components: **C**avus, **A**dduction (forefoot), **V**arus (heel), and **E**quinus (ankle). The high incidence and its classic presentation make it a frequent topic in postgraduate entrance exams. **Analysis of Options:** * **Congenital Clubfoot (Correct):** Its high prevalence (1:1000) and well-documented genetic/environmental etiology make it the most frequent among the listed options. * **Congenital Club Hand:** This is a longitudinal radial deficiency. While significant, it is much rarer than CTEV, occurring in approximately 1 in 30,000 to 100,000 births. * **Absence of Femur (PFFD):** Proximal Femoral Focal Deficiency is a rare developmental defect (1 in 50,000 births) involving the hip and femur. * **Absence of Fibula:** Fibular hemimelia is the most common long-bone deficiency, but its overall incidence (1 in 40,000) is still significantly lower than that of clubfoot. **High-Yield Clinical Pearls for NEET-PG:** 1. **Standard Treatment:** The **Ponseti Method** (serial casting) is the gold standard. The order of correction follows the acronym **CAVE** (Cavus first, then Adduction and Varus, finally Equinus). 2. **Pirani Score:** Used to assess the severity of CTEV and monitor progress during casting. 3. **Kite’s Angle:** On X-ray (AP view), the angle between the talus and calcaneus is **decreased** in CTEV (parallelism). 4. **Relapse Prevention:** After casting, a **Steenbeek or Denis Browne splint** is used (held in 70° external rotation) until age 3–4 years.

Question 82: Vertical talus is associated with:

A. Congenital flat foot (Correct Answer)
B. Ankle dislocation
C. Talus fracture
D. Pes cavus

Explanation: **Explanation:** **Congenital Vertical Talus (CVT)**, also known as **"Rocker-Bottom Foot,"** is a rare form of rigid congenital flat foot. The core pathology involves a fixed dorsal dislocation of the navicular on the head of the talus. Because the talus is locked in a vertical position (plantarflexed), the midfoot is displaced dorsally, resulting in the loss of the medial longitudinal arch and a characteristic convex appearance of the sole. **Analysis of Options:** * **A. Congenital flat foot (Correct):** CVT is the most severe form of rigid flat foot present at birth. Unlike flexible flat foot, it does not resolve with age and requires surgical intervention. * **B. Ankle dislocation:** While the talonavicular joint is dislocated, the ankle joint (talocrural joint) itself remains intact. * **C. Talus fracture:** Vertical talus is a congenital structural deformity, not a traumatic injury. Fractures of the talus in children are rare and usually result from high-energy trauma (e.g., Aviator’s fracture). * **D. Pes cavus:** This is a high-arched foot, the clinical opposite of the flat foot seen in CVT. Pes cavus is often associated with neuromuscular conditions like Friedreich’s ataxia or Charcot-Marie-Tooth disease. **NEET-PG High-Yield Pearls:** 1. **Radiological Hallmark:** On a lateral X-ray in forced plantarflexion, the talus remains vertical and does not align with the first metatarsal (the **Meary’s angle** remains increased). 2. **Associations:** Up to 50% of cases are associated with neuromuscular disorders like **Myelomeningocele** or chromosomal abnormalities (Trisomy 13, 15, 18). 3. **Differential Diagnosis:** Must be distinguished from **Calcaneovalgus foot**, which is a flexible postural deformity that corrects with passive stretching. 4. **Treatment:** The "Reverse Ponseti" technique (serial casting) followed by surgical pinning is the modern management approach.

Question 83: What is the known etiology of Perthes disease?

A. Pyogenic infection
B. Tubercular infection
C. Trauma
D. Unknown (Correct Answer)

Explanation: **Explanation:** **Legg-Calvé-Perthes Disease (LCPD)** is an idiopathic avascular necrosis of the femoral head occurring in children, typically between ages 4 and 8. **1. Why the correct answer is "Unknown":** Despite extensive research, the exact primary cause of Perthes disease remains **unknown (idiopathic)**. The underlying pathophysiology involves a temporary interruption of the blood supply to the capital femoral epiphysis, leading to bone infarction and subsequent remodeling. While various theories suggest associations with hypercoagulability (Protein C or S deficiency), venous obstruction, or delayed skeletal maturity, none have been definitively proven as the universal etiology. **2. Why the other options are incorrect:** * **Options A & B (Pyogenic/Tubercular Infection):** Perthes is a non-infectious, aseptic process. While Septic Arthritis (Pyogenic) or TB Hip can mimic the clinical presentation (limp and pain), they involve inflammatory markers (raised ESR/CRP) and joint destruction driven by pathogens, which are absent in Perthes. * **Option C (Trauma):** While a history of minor trauma is often reported by parents, it is generally considered an incidental finding that brings the pre-existing condition to medical attention rather than being the causative factor. **Clinical Pearls for NEET-PG:** * **Classic Presentation:** A painless (or mildly painful) limp in a young boy (Male:Female ratio = 4:1). * **Radiological Sign:** The **"Crescent Sign"** (subchondral fracture) is a pathognomonic early sign. * **Staging:** Commonly classified using the **Waldenström stages** (Initial, Fragmentation, Reossification, and Healed). * **Prognosis:** The most important prognostic factor is the **age at onset**; children younger than 6 years generally have better outcomes due to higher remodeling potential.

Question 84: Which classification system is NOT used for Perthes' disease?

A. Catterall classification
B. Salter Thompson classification
C. Stulberg classification
D. Salter Harris Classification (Correct Answer)

Explanation: **Explanation:** The correct answer is **D. Salter-Harris Classification**. This system is used to categorize **physeal (growth plate) fractures** in children based on the involvement of the epiphysis, physis, and metaphysis. It is not used for Perthes' disease, which is an idiopathic avascular necrosis of the femoral head. **Analysis of other options:** * **Catterall Classification:** Based on the extent of involvement of the femoral head seen on AP and lateral X-rays. It divides the disease into four groups (I-IV) based on the size of the necrotic segment. * **Salter-Thompson Classification:** A simplified version of Catterall’s, focusing on the extent of the **subchondral fracture (crescent sign)**. Group A involves less than half the head, while Group B involves more than half. * **Stulberg Classification:** This is used to assess the **long-term prognosis** and end-stage morphology of the hip after the disease has run its course. It classifies the femoral head shape (spherical, ovoid, or flat) and its congruency with the acetabulum. **High-Yield Clinical Pearls for NEET-PG:** * **Herring (Lateral Pillar) Classification:** Currently the most popular prognostic system. It is based on the height of the lateral pillar of the capital femoral epiphysis during the fragmentation stage. * **Age of Onset:** Typically occurs in children aged 4–8 years; more common in boys. * **Earliest Sign:** The earliest radiographic sign is often a **widening of the joint space** or a small, dense epiphysis. * **Gage’s Sign:** A V-shaped radiolucency on the lateral side of the epiphysis (a "Head-at-risk" sign).

Question 85: A one-and-a-half-year-old child fell while holding her father's hand. She subsequently cried and held her forearm in a pronated position, refusing to move the affected extremity. What is the most appropriate management at this stage?

A. Supinate the forearm (Correct Answer)
B. Examine the child under general anesthesia
C. Elevate the limb and observe
D. Investigate for osteomyelitis

Explanation: This clinical scenario describes a classic case of **Pulled Elbow** (also known as Nursemaid’s Elbow or Subluxation of the Radial Head). ### **Explanation of the Correct Answer** The injury occurs when sudden longitudinal traction is applied to an extended, pronated arm (e.g., a child being pulled up by the hand). In children under five, the **annular ligament** is relatively lax. This traction causes the radial head to slip partially out of the ligament, which then becomes trapped in the radio-capitellar joint. The management is **manual reduction**, which is diagnostic and therapeutic. The most common technique involves **supination of the forearm** followed by flexion at the elbow. A palpable "click" often signifies successful reduction, and the child typically resumes normal limb use within minutes. ### **Why Other Options are Incorrect** * **B. Examine under GA:** This is unnecessary and invasive. Pulled elbow is a clinical diagnosis that can be managed quickly in the outpatient department without anesthesia. * **C. Elevate and observe:** Observation will not resolve the mechanical entrapment of the ligament. Delaying reduction causes prolonged pain and distress. * **D. Investigate for osteomyelitis:** The acute history of trauma (pulling) and the specific "pronated" posture are classic for subluxation. Osteomyelitis presents with fever, constitutional symptoms, and localized inflammatory signs, which are absent here. ### **High-Yield Clinical Pearls for NEET-PG** * **Age Group:** Most common between **1–4 years** (rare after age 5 due to strengthening of the annular ligament). * **Clinical Posture:** The arm is held in slight flexion and **pronation** (the "pseudoparalysis" of the arm). * **Radiology:** X-rays are usually **normal** and are only indicated if a fracture is suspected (e.g., focal bone tenderness or significant swelling). * **Reduction Techniques:** 1. Supination-Flexion (traditional) or 2. Hyperpronation (often reported as more successful).

Question 86: Which of the following conditions is NOT associated with a bird-face appearance?

A. Bilateral temporomandibular joint ankylosis
B. Treacher Collins syndrome
C. Scleroderma (Correct Answer)
D. Pierre Robin syndrome

Explanation: **Explanation:** The "bird-face" appearance (micrognathia and retrognathia) is characterized by a receding chin and a prominent nose, typically resulting from the failure of normal mandibular development or restricted growth at the temporomandibular joint (TMJ). **Why Scleroderma is the Correct Answer:** Scleroderma (Systemic Sclerosis) is associated with a **"Mask-like" facies** or "Mousier facies." The skin becomes tight, shiny, and loses its folds. Characteristic features include microstomia (small mouth) and radial furrowing around the lips (Maussage sign), but it does not typically produce the skeletal retrognathia seen in bird-face appearance. **Analysis of Incorrect Options:** * **Bilateral TMJ Ankylosis:** If this occurs during the growth period (childhood), the mandible fails to grow forward and downward. This leads to severe retrognathia and a classic bird-face deformity. * **Treacher Collins Syndrome:** An autosomal dominant disorder of craniofacial development (1st and 2nd branchial arches). It presents with mandibular hypoplasia, malar hypoplasia, and downward-slanting palpebral fissures, creating a bird-like profile. * **Pierre Robin Syndrome:** A triad of micrognathia, glossoptosis (tongue falling back), and cleft palate. The underdeveloped mandible is a hallmark feature, leading to the bird-face look. **High-Yield Clinical Pearls for NEET-PG:** * **Bird-face appearance:** Think of conditions causing **Mandibular Hypoplasia.** * **Stickler Syndrome:** Another high-yield association with bird-face appearance and Pierre Robin sequence. * **Hallermann-Streiff Syndrome:** Also known as "Bird-headed dwarfism." * **Scleroderma:** Look for "Raynaud’s phenomenon" and "CREST syndrome" in the history to differentiate it from primary skeletal deformities.

Question 87: A six-year-old child presented with a gradually progressive valgus deformity at his right elbow for the past 3 years. He has a history of cast application for 6 weeks after a fall on an outstretched hand 3 years ago. What is the probable fracture that occurred?

A. Malunited lateral condylar fracture of the humerus (Correct Answer)
B. Malunited supracondylar fracture of the humerus
C. Posterior dislocation of the elbow
D. Fracture of the medial condyle of the humerus

Explanation: ### Explanation The correct answer is **Malunited lateral condylar fracture of the humerus**. **1. Why it is correct:** Lateral condyle fractures are "fractures of necessity" (usually requiring ORIF) because they are intra-articular and prone to non-union due to the pull of the extensor muscles and bathing in synovial fluid. If treated conservatively with a cast (as in this case), they often result in **non-union** or malunion. This leads to a cessation of growth on the lateral side of the distal humerus while the medial side continues to grow. This asymmetrical growth results in a **progressive cubitus valgus** deformity. **2. Why the other options are incorrect:** * **Malunited supracondylar fracture:** This is the most common pediatric elbow fracture. Malunion here typically results in **Cubitus Varus** (Gunstock deformity) due to coronal tilt, not progressive valgus. * **Posterior dislocation of the elbow:** While it can cause stiffness or heterotopic ossification, it does not typically result in a progressive angular deformity over years. * **Fracture of the medial condyle:** This is rare in children. If it leads to growth arrest or malunion, it would result in a **cubitus varus** deformity. **3. Clinical Pearls for NEET-PG:** * **Tardy Ulnar Nerve Palsy:** A classic complication of long-standing cubitus valgus (secondary to lateral condyle non-union). The ulnar nerve gets stretched over the medial epicondyle. * **Milch Classification:** Used for lateral condyle fractures (Type I: through the epiphysis; Type II: through the physis—most common). * **Progressive vs. Static:** Supracondylar malunion is a **static** deformity (occurs at the time of healing), whereas lateral condyle non-union causes a **progressive** deformity (due to growth plate disturbance).

Question 88: In a newborn child, abduction and internal rotation producing a click sound is indicative of which sign?

A. Ortolani's sign (Correct Answer)
B. Telescoping sign
C. Lachman's sign
D. Mc Murray's sign

Explanation: ### Explanation **Correct Answer: A. Ortolani's sign** **Understanding the Concept:** Ortolani’s sign is a clinical test used to identify a **dislocated hip** that is **reducible** in newborns with Developmental Dysplasia of the Hip (DDH). * **Mechanism:** The examiner flexes the infant’s hips and knees to 90 degrees. The hips are then gently **abducted** while applying anterior pressure on the greater trochanter. * **The "Click":** If the hip is dislocated, this maneuver forces the femoral head back into the acetabulum. The palpable (and sometimes audible) "clunk" or "click" as the femoral head slips over the posterior acetabular rim into the socket constitutes a positive Ortolani sign. **Analysis of Incorrect Options:** * **B. Telescoping sign:** This is seen in a **neglected or fixed dislocation**. When the femur is pushed up and pulled down along its long axis, it moves excessively due to the lack of a stable fulcrum in the acetabulum. * **C. Lachman's sign:** This is the most sensitive clinical test for an **Anterior Cruciate Ligament (ACL) tear** in the knee, not related to pediatric hip dysplasia. * **D. McMurray's sign:** This test is used to diagnose **meniscal tears** in the knee by rotating the tibia on the femur. **High-Yield Clinical Pearls for NEET-PG:** * **Barlow’s Test:** The opposite of Ortolani; it is a **provocative test** where the hip is adducted and pushed posteriorly to see if it "dislocates" (identifies an unstable but reduced hip). * **Sequence:** Remember **"O" for Out** (Ortolani reduces a dislocated hip) and **"B" for Back** (Barlow pushes it back/out). * **Age Factor:** Ortolani and Barlow signs are usually only reliable up to **2–3 months of age**. After this, soft tissue contractures develop, and **limited abduction** becomes the most reliable clinical sign of DDH. * **Investigation of Choice:** Ultrasound (USG) is preferred for infants <6 months; X-ray is used for infants >6 months (once the femoral head ossifies).

Question 89: Which of the following terms is synonymous with Blount's disease?

A. Genu Valgum
B. Infantile Tibia Vara (Correct Answer)
C. Genu Recurvatum
D. Adolescent tibia vara

Explanation: **Explanation:** **Blount’s Disease** is a developmental disorder characterized by disordered endochondral ossification of the medial aspect of the proximal tibial physis. This leads to a progressive varus deformity (bowing) of the legs. 1. **Why the correct answer is right:** The term **Infantile Tibia Vara** is synonymous with the early-onset form of Blount's disease (typically appearing between ages 2–5). It is the most common presentation of the condition. The underlying pathology involves excessive compressive forces across the medial growth plate, leading to growth suppression (Heuter-Volkmann Law) and subsequent medial tibial beaking. 2. **Why the incorrect options are wrong:** * **Genu Valgum:** This refers to "knock-knees," where the knees angle in and the ankles are apart. Blount’s disease causes Genu Varum (bow-legs). * **Genu Recurvatum:** This refers to hyperextension of the knee joint, which is not the primary deformity in Blount’s. * **Adolescent Tibia Vara:** While this is a form of Blount's disease (late-onset), it is not considered a *synonym* for the disease as a whole. "Tibia Vara" is the general clinical term, but "Infantile Tibia Vara" is the classic synonym used in textbooks to describe the primary entity. **High-Yield Clinical Pearls for NEET-PG:** * **Radiographic Hallmark:** The **Drennan’s Metaphyseal-Diaphyseal Angle (MDA)**. An angle **>16°** is highly suggestive of Blount’s rather than physiologic bowing. * **Langenskiöld Classification:** Used to stage the severity based on the degree of metaphyseal depression and epiphyseal changes (Stages I-VI). * **Risk Factors:** Early walking, obesity, and African-American ethnicity. * **Treatment:** Bracing (KAFO) is effective for Stage I-II in children <3 years; surgical osteotomy is required for advanced stages or older children.

Question 90: A one-year-old child presented with multiple fractures in various stages of healing. What is the most probable diagnosis in this case?

A. Scurvy
B. Rickets
C. Battered baby syndrome (Correct Answer)
D. Sickle cell disease

Explanation: **Explanation:** The presentation of **multiple fractures in various stages of healing** (metachronous fractures) in an infant is a classic hallmark of **Battered Baby Syndrome** (Non-Accidental Injury). **Why Option C is correct:** In cases of physical abuse, injuries occur at different points in time, leading to radiological evidence of fractures with varying degrees of callus formation. High-yield diagnostic features include: * **Metaphyseal Corner Fractures** (Bucket-handle fractures): Highly specific for abuse. * **Multiple Rib Fractures:** Especially posterior rib fractures. * **Fractures in unusual sites:** Scapula, outer end of the clavicle, or sternum. * **Discrepancy** between the history provided by the caregiver and the clinical findings. **Why the other options are incorrect:** * **Scurvy (Vitamin C deficiency):** Typically presents with subperiosteal hemorrhage, "Pelkan’s spur," and "Wimberger’s ring sign." While it causes bone fragility, the classic radiological signs are distinct from simple multiple fractures. * **Rickets:** Characterized by cupping, splaying, and fraying of the metaphysis and a widened growth plate. While "Looser’s zones" (pseudofractures) can occur, multiple healing long-bone fractures are not the primary presentation. * **Sickle Cell Disease:** Primarily presents with "Hand-foot syndrome" (dactylitis) in infants or osteomyelitis (Salmonella). It does not typically present with multiple healing fractures. **NEET-PG High-Yield Pearls:** 1. **Osteogenesis Imperfecta (OI):** The most important differential diagnosis for Battered Baby Syndrome. Look for blue sclera, dentinogenesis imperfecta, and a family history. 2. **Legal Obligation:** In suspected cases of child abuse, the physician's priority is the safety of the child (hospitalization) and mandatory reporting to authorities. 3. **Dating Fractures:** The presence of a "soft callus" suggests an injury 1–2 weeks old, while a "hard callus" suggests 3–6 weeks.

Practice by Chapter

Developmental Dysplasia of Hip

Practice Questions

Clubfoot

Practice Questions

Pediatric Fractures

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Growth Plate Injuries

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Legg-Calvé-Perthes Disease

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Slipped Capital Femoral Epiphysis

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Pediatric Spine Deformities

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Cerebral Palsy: Orthopaedic Aspects

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Neuromuscular Disorders in Children

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Pediatric Bone and Joint Infections

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Limb Length Discrepancies

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Orthopedic Manifestations of Genetic Disorders

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