4. Pediatrics MCQs

A newborn infant is noted to have a painless, mobile swelling over the middle third of the right collarbone. There is no history of birth trauma. Radiographs show a distinct gap in the mid-clavicle with smooth, rounded bone ends. What is the most appropriate initial management for this condition?

A neonate presents with severe bilateral foreshortening of the forearms and clubhands. Clinical examination reveals the absolute absence of the thumbs bilaterally. Echocardiography shows an atrial septal defect. Which of the following is the most likely genetic mutation associated with this presentation?

A 35-year-old presents with chronic pain and stiffness in the right lower extremity. Radiographs show dense, undulating cortical hyperostosis resembling "flowing candle wax" along the medial cortex of the femur and tibia. Which somatic mutation is classically linked to this sporadic condition?

A newborn male is noted to have a hypoplastic right hand with symbrachydactyly. On examination, there is an absent anterior axillary fold on the ipsilateral side. What is the most widely accepted vascular etiology for this congenital anomaly?

A 3-year-old girl has congenital absence of the right thumb and a hypoplastic radius. An echocardiogram reveals an atrial septal defect. Which gene mutation is responsible for this autosomal dominant condition?

A 2-year-old child presents with unilateral tibia vara. Radiographs reveal a sharply demarcated, radiolucent defect in the medial cortex of the proximal metaphysis of the tibia with surrounding sclerosis. What is the recommended initial management for this specific lesion?

A 5-year-old girl presents with disproportionate overgrowth of her right index and middle fingers. Histological examination reveals extensive fibrofatty infiltration along the digital nerve sheaths. Which of the following genetic mutations is primarily implicated in this localized dysplasia?

An infant is diagnosed with unilateral fibular hemimelia. Which of the following associated clinical findings is most likely to be present in the affected limb?

A 3-year-old child is brought to the clinic due to an inability to supinate the right forearm. Radiographs reveal bony continuity between the proximal radius and ulna. At what stage of embryonic development does the failure of longitudinal segmentation occur to cause this localized anomaly?

A 1-year-old boy presents with an isolated limb length discrepancy. Radiographs show a shortened right femur with a normally articulated hip and knee, but with significant coxa vara (neck-shaft angle of 85 degrees). There is no pseudoarthrosis. Which of the following is the most appropriate initial management for the coxa vara?

A neonate is diagnosed with bilateral radial clubhand and profoundly low platelets. Interestingly, the child's thumbs are present. What is the typical natural history of the thrombocytopenia in this specific syndrome?

A 10-year-old girl with a low posterior hairline and short, webbed neck is diagnosed with Klippel-Feil syndrome. She also has a unilateral undescended scapula. What is the approximate reported incidence of Sprengel deformity in patients with Klippel-Feil syndrome?

A newborn is evaluated for a sharp posteromedial angulation at the junction of the middle and distal thirds of the left tibia. The foot is held in a severe calcaneovalgus position. What is the expected natural history of the tibial angulation and the limb length discrepancy (LLD)?

A 3-month-old infant is brought to the clinic with excessive crying, fever, and a noticeably swollen jaw. Radiographs exhibit pronounced subperiosteal new bone formation exclusively along the mandible. The parents are reassured that symptoms typically resolve spontaneously by age 2. Which collagen gene defect is implicated in this self-limiting condition?

When optimizing the biomechanical stability of an Ilizarov circular external fixator, which of the following frame modifications will most effectively increase the bending stiffness of the construct?

Which of the following modifications most effectively increases the axial stiffness of an Ilizarov circular ring fixator construct?

A 10-year-old child undergoes guided growth with a medial tension band plate for genu valgum. The implant exerts its corrective effect primarily through which of the following biological principles?