Pediatric Orthopaedics — MCQs

Pediatric Orthopaedics Indian Medical PG Practice Questions and MCQs

Question 171: Pseudoflexion deformity of the hip is typically seen in which of the following conditions?

A. Iliopsoas abscess (Correct Answer)
B. Tom Smith arthritis
C. Rickets
D. Posterior dislocation of the hip

Explanation: ### Explanation **Correct Answer: A. Iliopsoas Abscess** **Why it is correct:** The term **Pseudoflexion deformity** refers to a clinical presentation where the hip appears to be in a fixed flexion deformity (FFD), but the underlying joint itself is healthy. In an **Iliopsoas abscess**, the collection of pus irritates the iliopsoas muscle, causing it to go into a protective spasm. Since the iliopsoas is the primary flexor of the hip, the patient holds the hip in flexion to minimize tension on the muscle and reduce pain. The key diagnostic feature is that while extension is painful and restricted, **internal and external rotation of the hip are preserved and painless** when the hip is in a flexed position. This distinguishes it from true intra-articular pathology where all movements are restricted. **Why other options are incorrect:** * **Tom Smith Arthritis:** This is septic arthritis of the infancy. It involves the destruction of the femoral head/epiphysis, leading to a **true deformity** and global restriction of all hip movements. * **Rickets:** Typically presents with bony deformities like coxa vara, genu valgum, or genu varum due to softened osteoid, but it does not cause an acute pseudoflexion deformity. * **Posterior Dislocation of the Hip:** This presents with a characteristic position of **flexion, adduction, and internal rotation**. This is a true structural deformity resulting from the displacement of the femoral head, not a "pseudo" deformity. **High-Yield Clinical Pearls for NEET-PG:** * **Psoas Sign:** Pain on passive extension of the hip; a classic sign of psoas irritation (abscess or retrocecal appendicitis). * **Thomas Test:** Used to measure Fixed Flexion Deformity (FFD). In pseudoflexion, the test may be positive, but the preservation of rotations helps localize the pathology to the muscle rather than the joint. * **Triad of Psoas Abscess:** Fever, flank pain, and limp (or restricted hip extension).

Question 172: What is the treatment of choice for a fracture of the shaft of the femur in a child less than 2 years of age?

A. Gallows traction (Correct Answer)
B. Hip spica cast
C. Russell traction
D. Intramedullary nail

Explanation: **Explanation:** The management of pediatric femoral shaft fractures is primarily determined by the **age and weight** of the child. **Why Gallows Traction is Correct:** Gallows traction (also known as Bryant’s traction) is the treatment of choice for children **under 2 years of age** (or weighing less than 12–15 kg). In this method, both legs are suspended vertically using skin traction such that the buttocks are just lifted off the bed. The child’s body weight acts as counter-traction. It is preferred because it allows for easy nursing care and diapering while maintaining alignment in a population where rapid remodeling occurs. **Analysis of Incorrect Options:** * **Hip Spica Cast:** While often used for children aged 6 months to 5 years, it is typically the primary treatment for stable fractures or used *after* a brief period of traction. In very young infants (<2 years), Gallows is traditionally the first-line teaching for exams. * **Russell Traction:** This is a form of skin traction used for older children (usually >5 years) or adults for pre-operative stabilization. It involves a sling under the knee and does not suspend the patient vertically. * **Intramedullary (IM) Nail:** Rigid IM nails are contraindicated in young children due to the risk of damaging the trochanteric epiphysis and blood supply to the femoral head (leading to AVN). Flexible (Elastic) nails are used for children aged 5–12 years. **NEET-PG High-Yield Pearls:** * **Age < 2 years:** Gallows Traction. * **Age 2–5 years:** Immediate Hip Spica (if shortening <2cm) or Traction followed by Spica. * **Age 6–12 years:** Titanium Elastic Nailing System (TENS). * **Age > 12 years:** Lateral entry Rigid Intramedullary Nail. * **Caution:** In Gallows traction, always monitor **peripheral circulation** (dorsalis pedis pulse) to prevent compartment syndrome or ischemia.

Question 173: Arrange the following diseases in order of the zones of their involvement while going from metaphysis to epiphysis: Gigantism, Rickets, Gaucher's disease, Scurvy?

A. Scurvy - Rickets - Gaucher's disease - Gigantism
B. Scurvy - Rickets - Gigantism - Gaucher's disease (Correct Answer)
C. Gigantism - Scurvy - Gaucher's disease - Rickets
D. Rickets - Scurvy - Gigantism - Gaucher's disease

Explanation: To solve this question, one must understand the micro-anatomy of the long bone and where specific metabolic and genetic pathologies manifest. The sequence requested is from **Metaphysis to Epiphysis**. ### 1. The Correct Sequence (Option B) * **Scurvy (Metaphysis):** Vitamin C deficiency leads to defective osteoid formation. The primary pathology occurs in the **metaphysis**, specifically at the "Zone of Provisional Calcification," leading to the classic "Trummerfeld zone" (zone of rarefaction). * **Rickets (Physis - Hypertrophic Zone):** Rickets is characterized by a failure of mineralization of the osteoid. This occurs predominantly in the **hypertrophic zone of the growth plate (physis)**, causing the characteristic widening and cupping seen on X-rays. * **Gigantism (Physis - Proliferative Zone):** Excess Growth Hormone acts on the **proliferative zone of the physis**, leading to increased longitudinal bone growth before the epiphyses fuse. * **Gaucher’s Disease (Epiphysis/Subchondral):** While Gaucher’s affects the marrow (Erlenmeyer flask deformity in metaphysis), its most definitive orthopedic complication is **Avascular Necrosis (AVN)**, which primarily involves the **epiphysis**. ### 2. Why Other Options are Wrong * **Options A, C, and D** are incorrect because they misplace the anatomical site of pathology. For example, placing Gigantism before Rickets ignores that GH stimulates the proliferative layer (closer to the epiphysis), whereas Rickets affects the mineralizing hypertrophic layer (closer to the metaphysis). ### 3. High-Yield NEET-PG Pearls * **Scurvy:** Look for Wimberger’s ring sign and Pelkan spurs. * **Rickets:** Look for "Cupping, Fraying, and Splaying" of the metaphysis. * **Achondroplasia:** Affects the **proliferative zone** (failure of chondrocyte proliferation). * **Memory Aid:** From Metaphysis $\rightarrow$ Epiphysis: **S**curvy (Metaphysis) $\rightarrow$ **R**ickets (Hypertrophic) $\rightarrow$ **A**chondroplasia/**G**igantism (Proliferative) $\rightarrow$ **G**aucher's/AVN (Epiphysis).

Question 174: Bilateral congenital dislocation of the hip is associated with all, EXCEPT:

A. Lordotic spine
B. Excess genu valgum (Correct Answer)
C. Waddling gait
D. Shelton's line deformity

Explanation: In **Developmental Dysplasia of the Hip (DDH)**, specifically bilateral congenital dislocation, the femoral head is displaced superiorly and posteriorly out of the acetabulum. This structural change alters the biomechanics of the pelvis and lower limbs. **Explanation of the Correct Answer:** * **Option B (Excess genu valgum):** This is the correct answer because it is **not** typically associated with DDH. In fact, patients with DDH often exhibit a "pseudo-genu varum" appearance or neutral alignment. Genu valgum (knock-knees) is more commonly associated with conditions like rickets or certain skeletal dysplasias, rather than isolated hip dislocation. **Analysis of Incorrect Options:** * **Option A (Lordotic spine):** In bilateral dislocation, the center of gravity shifts forward because the femoral heads are posterior to the acetabulum. To maintain balance, the patient compensates by increasing the lumbar curvature, leading to **exaggerated lumbar lordosis**. * **Option C (Waddling gait):** Due to the lack of a stable fulcrum (dislocated hip) and the resulting functional shortening/weakness of the gluteus medius muscles, the patient exhibits a bilateral Trendelenburg gait, commonly known as a **waddling gait**. * **Option D (Shenton’s line deformity):** Shenton’s line is an imaginary curved line formed by the inferior border of the pubic ramus and the medial margin of the femoral neck. In DDH, the superior displacement of the femur **breaks this continuity**, making it a hallmark radiological sign. **Clinical Pearls for NEET-PG:** * **Trendelenburg Test:** Positive in DDH due to abductor insufficiency. * **Galeazzi Sign:** Used for unilateral DDH (apparent shortening of the femur). * **Ortolani & Barlow Maneuvers:** Most reliable clinical tests for neonatal screening (up to 2-3 months). * **Radiology:** Von Rosen’s view is used for diagnosis; Perkins' line and Hilgenreiner's line help define the quadrants of dislocation.

Question 175: Which gene mutation is seen in Marfan syndrome?

A. Fibrillin-1 gene (Correct Answer)
B. FGFR-3 gene
C. COL1A1 gene
D. Fibrillin-2 gene

Explanation: **Explanation:** **Marfan Syndrome** is an autosomal dominant connective tissue disorder characterized by mutations in the **FBN1 gene** located on **chromosome 15q21.1**. This gene encodes **Fibrillin-1**, a glycoprotein essential for the formation of elastic fibers in the extracellular matrix. Fibrillin-1 also plays a critical role in sequestering Transforming Growth Factor-beta (TGF-β); its deficiency leads to excess TGF-β signaling, resulting in the characteristic overgrowth of long bones and weakening of connective tissues. **Analysis of Incorrect Options:** * **FGFR-3 gene (Option B):** Mutations in the Fibroblast Growth Factor Receptor 3 gene lead to **Achondroplasia**, the most common cause of dwarfism. * **COL1A1 gene (Option C):** Mutations in Collagen Type 1 (COL1A1/COL1A2) are associated with **Osteogenesis Imperfecta**, characterized by bone fragility and blue sclera. * **Fibrillin-2 gene (Option D):** Mutations in the FBN2 gene (chromosome 5) cause **Beals Syndrome** (Congenital Contractural Arachnodactyly), which mimics Marfanoid features but presents with multiple joint contractures and "crumpled" ears. **High-Yield Clinical Pearls for NEET-PG:** * **Skeletal:** Arachnodactyly (long fingers), pectus excavatum/carinatum, and scoliosis. * **Ocular:** **Ectopia lentis** (dislocation of the lens), typically **superior-temporal** (upward). * **Cardiovascular:** The most serious complications are **Aortic Root Dilation** and Aortic Dissection. * **Diagnostic Criteria:** Based on the **Revised Ghent Nosology**, focusing on FBN1 mutation, aortic root aneurysm, and ectopia lentis.

Question 176: A metaphyseal fracture that touches the physis but does not cross it is classified under which type of Salter-Harris physeal injury?

A. Type I
B. Type II (Correct Answer)
C. Type III
D. Type IV

Explanation: The **Salter-Harris classification** is the most widely used system to describe physeal (growth plate) injuries in children. The classification is based on the involvement of the physis, epiphysis, and metaphysis. ### **Explanation of the Correct Answer** **Option B (Type II)** is correct because it involves a fracture through the **physis** that extends upwards into the **metaphysis**. In this injury, the fracture line "touches" the physis and travels along it before exiting through the metaphyseal bone. This results in a triangular fragment of the metaphysis remaining attached to the epiphysis, known as the **Thurston-Holland sign**. Type II is the most common type of Salter-Harris fracture. ### **Why Other Options are Incorrect** * **Type I:** The fracture occurs exclusively through the **physis** (hypertrophic zone). It does not involve the metaphysis or epiphysis. It is often a clinical diagnosis as X-rays may appear normal. * **Type III:** The fracture line runs through the physis and extends downwards into the **epiphysis** (intra-articular). It does not touch the metaphysis. * **Type IV:** This is a vertical fracture that crosses **all three layers**: the metaphysis, the physis, and the epiphysis. It is intra-articular and carries a high risk of growth arrest. ### **NEET-PG High-Yield Pearls** * **Mnemonic (SALTER):** * **S** (Type I): **S**lip (Separated physis) * **A** (Type II): **A**bove (Metaphysis) — *Most common* * **L** (Type III): **L**ower (Epiphysis) * **T** (Type IV): **T**hrough (Metaphysis, Physis, and Epiphysis) * **ER** (Type V): **ER**asure/Crush (Compression of physis) — *Worst prognosis* * **Prognosis:** Types I and II usually have a good prognosis and can be managed conservatively. Types III and IV are intra-articular and often require Open Reduction and Internal Fixation (ORIF) to prevent joint incongruity and growth plate closure.

Question 177: Triple arthrodesis involves which of the following joints?

A. Calcaneocuboid, talonavicular, and talocalcaneal joints (Correct Answer)
B. Tibiotalar, calcaneocuboid, and talonavicular joints
C. Ankle joint, calcaneocuboid, and talonavicular joints
D. None of the above

Explanation: **Explanation:** Triple arthrodesis is a surgical procedure aimed at stabilizing the hindfoot and correcting deformities by fusing three specific joints. The primary goal is to provide a stable, plantigrade, and pain-free foot, often in cases of neuromuscular imbalances (like Polio or Charcot-Marie-Tooth disease) or severe degenerative arthritis. **1. Why Option A is correct:** The "triple" in the name refers to the fusion of the three main joints of the hindfoot complex: * **Talocalcaneal (Subtalar) joint:** Controls inversion and eversion. * **Talonavicular joint:** Part of the transverse tarsal joint; critical for midfoot stability. * **Calcaneocuboid joint:** The lateral component of the transverse tarsal joint. Fusing these three eliminates motion in the hindfoot while preserving motion at the ankle (tibiotalar) joint. **2. Why other options are incorrect:** * **Options B and C** are incorrect because they include the **Tibiotalar (Ankle) joint**. Fusing the ankle joint along with the hindfoot joints is termed a "pantalar arthrodesis," not a triple arthrodesis. The ankle joint must remain mobile in a standard triple arthrodesis to allow for dorsiflexion and plantarflexion. **Clinical Pearls for NEET-PG:** * **Indications:** Rigid clubfoot (relapsed), paralytic vertical talus, and rheumatoid arthritis. * **Age Criterion:** Ideally performed after skeletal maturity (usually **>10–12 years**) to avoid interfering with the growth of the tarsal bones. * **Sequence of Fusion:** During surgery, the **Talonavicular joint** is considered the "key" to the reduction and is typically addressed first to set the alignment of the medial longitudinal arch. * **Post-op:** It results in the loss of side-to-side (inversion/eversion) movement, making walking on uneven ground difficult.

Question 178: Salter Harris classification is used for what type of injury?

A. Supracondylar humerus fractures in children
B. Estimation of growth of the physes
C. Physeal injuries (Correct Answer)
D. Severity of degloving injuries to the limb

Explanation: The **Salter-Harris classification** is the most widely used system for categorizing fractures that involve the **epiphyseal plate (physeal/growth plate)** in children. Because the physis is the weakest part of the pediatric skeleton, it is more prone to injury than the surrounding ligaments. ### Why the Correct Answer is Right: The classification (Types I–V) is based on the involvement of the physis, epiphysis, and metaphysis. This is crucial because injuries involving the physis can lead to premature closure, resulting in limb length discrepancy or angular deformities. * **Type I:** Slipped (through physis only) * **Type II:** Above (physis + metaphysis) – **Most common type** * **Type III:** Lower (physis + epiphysis) – Intra-articular * **Type IV:** Through (metaphysis + physis + epiphysis) – Intra-articular * **Type V:** Erased/Rammed (compression injury) – Worst prognosis ### Why Other Options are Wrong: * **Option A:** Supracondylar humerus fractures are classified using the **Gartland Classification**. * **Option B:** Growth of the physis is estimated using tools like the **Risser’s sign** (for scoliosis) or the **Tanner-Whitehouse method**, not Salter-Harris. * **Option D:** Degloving or open injuries are typically graded using the **Gustilo-Anderson classification** or the **Mangled Extremity Severity Score (MESS)**. ### High-Yield Clinical Pearls for NEET-PG: * **Mnemonic:** **S-A-L-T-R** (Slipped, Above, Lower, Through, Rammed). * **Type II** is the most common overall. * **Types III and IV** require anatomical reduction because they are intra-articular and cross the germinal layer of the physis. * **Type V** has the highest risk of growth arrest but is often diagnosed retrospectively. * **Thurston-Holland Sign:** The triangular metaphyseal fragment seen in Type II fractures.

Question 179: How should failure of the Ponsetti technique in children be managed?

A. Posteromedial soft tissue release (Correct Answer)
B. Anterolateral soft tissue release
C. Triple arthrodesis
D. Lateral closing wedge osteotomy of calcaneum

Explanation: ### Explanation The **Ponseti technique** is the gold standard for managing Congenital Talipes Equinovarus (CTEV), involving serial casting followed by a tenotomy. When this conservative approach fails or in cases of late presentation (neglected clubfoot), surgical intervention becomes necessary. **1. Why Posteromedial Soft Tissue Release (PMSTR) is correct:** The primary pathology in CTEV involves contractures of the posterior and medial structures (Achilles tendon, tibialis posterior, flexor digitorum longus, and flexor hallucis longus) and associated joint capsules. **PMSTR (Turco’s procedure)** is the standard surgical salvage for failed conservative management. It involves releasing these tight structures to realign the talonavicular, subtalar, and ankle joints. **2. Why the other options are incorrect:** * **Anterolateral soft tissue release:** This is anatomically incorrect for CTEV. The deformity is characterized by varus and equinus, which are medial and posterior pathologies, not lateral. * **Triple arthrodesis:** This is a salvage procedure involving the fusion of the subtalar, talonavicular, and calcaneocuboid joints. It is reserved for **skeletally mature patients** (usually >10–12 years) with severe, rigid deformities, not as the first-line surgical response to Ponseti failure in younger children. * **Lateral closing wedge osteotomy (Dwyer’s):** This is used specifically to correct calcaneal varus. While it may be part of a larger reconstruction, it does not address the global multi-planar deformity of clubfoot as comprehensively as PMSTR. ### Clinical Pearls for NEET-PG: * **Order of correction in Ponseti (CAVE):** **C**avus $\rightarrow$ **A**dductus $\rightarrow$ **V**arus $\rightarrow$ **E**quinus. * **Pirani Score:** Used to assess the severity of CTEV and monitor progress during casting. * **Relapse:** The most common cause of failure/relapse in the Ponseti method is **non-compliance with the Steenbeek foot abduction brace**. * **Age for PMSTR:** Typically performed between 6 months and 2 years if casting fails.

Question 180: Which is the most common bone fractured during birth?

A. Clavicle
B. Humerus (Correct Answer)
C. Femur
D. None of the above

Explanation: **Explanation:** The correct answer is **Humerus**. While historically the clavicle was cited as the most common birth-related fracture, recent epidemiological data and clinical studies (often cited in standard orthopaedic textbooks like Campbell’s) indicate that the **humerus** is the most frequently fractured bone during the delivery process, particularly in cases of shoulder dystocia or breech presentations. **Breakdown of Options:** * **Humerus (Correct):** It is the most common long bone fracture. It typically occurs during the delivery of the extended arms in a breech presentation or during maneuvers to resolve shoulder dystocia in a cephalic presentation. Most are "greenstick" or displaced midshaft fractures. * **Clavicle (Incorrect):** Although very common and often cited in older literature as the most frequent, it is frequently asymptomatic and may go undiagnosed until a callus forms. In many modern competitive exams, the humerus is prioritized as the most common "documented" bone fracture. * **Femur (Incorrect):** This is much less common than humeral or clavicular fractures. It usually occurs during a difficult breech extraction when traction is applied to the lower extremities. **Clinical Pearls for NEET-PG:** 1. **Presentation:** Most neonatal fractures present with **pseudoparalysis** (the infant avoids moving the limb due to pain), which must be differentiated from Erb’s palsy. 2. **Management:** Neonatal fractures have an immense remodeling potential. Humerus fractures are typically treated with simple immobilization (pinning the sleeve to the shirt) for 2–3 weeks. 3. **Healing:** A visible callus usually forms within 7–10 days, which is often how undiagnosed clavicle fractures are eventually discovered. 4. **Prognosis:** Excellent; permanent deformity or limb length discrepancy is extremely rare due to rapid remodeling at this age.

Practice by Chapter

Developmental Dysplasia of Hip

Practice Questions

Clubfoot

Practice Questions

Pediatric Fractures

Practice Questions

Growth Plate Injuries

Practice Questions

Legg-Calvé-Perthes Disease

Practice Questions

Slipped Capital Femoral Epiphysis

Practice Questions

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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