Menu

4. Pediatrics MCQs

Practice Set 271 of 334

This practice set contains high-yield board review questions covering key concepts in 4. Pediatrics. Each clinical scenario is designed to test your diagnostic and management skills relevant to this subspecialty.

Question 5401

Topic: 4. Pediatrics

A 24-year-old man presents with a short forearm and a hand deformity. The patient is otherwise healthy with no other congenital defects. The clinical appearance of his forearm is shown (). Although the patient has a thumb, it is in an abnormal position. Any attempt to make his thumb more functional will be influenced by:

. Index finger camptodactyly
. Presence of a side-to-side finger grip
. Stiff fingers
. Recurrence of radial club hand
. Radial bowing

Correct Answer & Explanation

. Presence of a side-to-side finger grip

Explanation

The pattern of usage of the hand is established in the brain by 2 to 3 years of age. Although pollicization has been performed in adolescents, patients continue to prefer a scissor pinch. At 24 years of age, this pattern will be well established. The patient can be coaxed to use his thumb, but it will not be involuntary and automatic.

Question 5402

Topic: Pediatric Upper Extremity & Spine
A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; platelet 254×10^3 mcu/L; neutrophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. Diagnosis is:
. Vertebral defects, anal atresia, tracheoesophageal fistula with esophageal atresia, and radial and renal anomalies (VATER)
. Abnormalities of vertebrae, anus, cardiovascular tree, trachea, esophagus, renal system, and limb buds (VACTERL)
. Thrombocytopenia absent radii (TAR) syndrome
. Holt-Oram syndrome
. Fanconi's anemia

Correct Answer & Explanation

. Holt-Oram syndrome

Explanation

The patient has a radial club hand with a cardiac defect. Because the spine radiograph is normal, the diagnosis cannot be VATER or VACTERL anomaly as both involve vertebrae. Blood work up is normal, making this diagnosis Holt-Oram syndrome.

Question 5403

Topic: Pediatric Upper Extremity & Spine

The principal abnormality associated with Holt-Oram syndrome is:

. Platelet deficiency
. C ardiac defects
. Pancytopenia
. Malignancy
. Vertebral defects

Correct Answer & Explanation

. C ardiac defects

Explanation

Holt-Oram syndrome is associated with cardiac defects. The most common defect is aldosterone secretion.

Question 5404

Topic: Pediatric Upper Extremity & Spine
A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; platelet 254×10^3 mcu/L; neutrophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. The next step in the management of the radial club hand is:
. Stretching
. Soft-tissue distraction
. Radialization
. Centralization
. Pollicization

Correct Answer & Explanation

. Stretching

Explanation

For the first 6 to 9 months, parents and therapists perform passive stretching. Serial casting and splinting may also be used. Sometimes, preoperative soft-tissue distraction is performed, usually before a wrist stabilization procedure.

Question 5405

Topic: 4. Pediatrics
A 15-day-old boy presents with deformity of the right hand. The boy was delivered prematurely and underwent an urgent arterial switch for transposition of great vessels. The patient is in stable condition. He has a radial club hand, and because the radial head cannot be palpated, total absence of radius is suspected. The thumb is absent and the index finger has camptodactyly. The forearm is short compared to the left side, and the patient flexes his elbow upon stimulation. Spontaneous finger motion is also present. A thorough physical examination is performed and a set of investigations is ordered. The results are as follows: complete blood count 10,000 mcu/L; platelet 254×10^3 mcu/L; neutrophils 50%; Hb 14.2 mg/dL; lymphocytes 40%; Hct 45; and monocytes 10%. No renal abnormalities were noted on ultrasonogram of the abdomen. A radiograph of the spine is normal. When the patient is 10 years old, he is not satisfied with the length of his forearm and wishes to lengthen it. Which of the following is not a satisfactory recommendation:
. Acute lengthening with bone graft
. Circular ring fixator and gradual distraction
. Hybrid frame and distraction using the Ilizarov method
. External frame and distraction using De Bastiani's principles
. Lengthening

Correct Answer & Explanation

. Acute lengthening with bone graft

Explanation

Acute lengthening is done for small defects and, if performed in this patient, may result in severe neurovascular compromise.

Question 5406

Topic: Pediatric Hip

A 13-year-old obese male presents with a 3-week history of vague right groin and knee pain. He walks with an antalgic limp. On physical examination, as his right hip is passively flexed, it obligatorily falls into external rotation. Radiographs confirm the diagnosis. Which of the following is the gold standard initial management?

. Application of a hip spica cast in internal rotation
. In situ pinning with a single cannulated screw
. Open reduction and internal fixation through a Smith-Petersen approach
. Closed reduction and percutaneous pinning
. Proximal femoral osteotomy to correct the deformity

Correct Answer & Explanation

. In situ pinning with a single cannulated screw

Explanation

The clinical presentation is classic for a slipped capital femoral epiphysis (SCFE). In situ pinning with a single cannulated screw placed in the center of the epiphysis is the gold standard to prevent further slippage.

Question 5407

Topic: Pediatric Hip

A 4-month-old female with developmental dysplasia of the hip (DDH) has been treated with a Pavlik harness for 4 weeks. Serial ultrasounds confirm that the hip remains dislocated despite verifiable compliance and proper harness application. What is the most appropriate next step in management?

. Continue the Pavlik harness for an additional 4 weeks
. Transition to a rigid abduction orthosis (e.g., Ilfeld splint)
. Perform an immediate open reduction and capsulorrhaphy
. Perform a closed reduction and application of a spica cast under general anesthesia
. Observe and delay treatment until the child begins walking

Correct Answer & Explanation

. Transition to a rigid abduction orthosis (e.g., Ilfeld splint)

Explanation

If a Pavlik harness fails to achieve reduction after 3 to 4 weeks, continuing it increases the risk of 'Pavlik harness disease' (erosion of the posterior acetabulum). The next appropriate non-operative step is transitioning to a rigid abduction orthosis.

Question 5408

Topic: Pediatric Upper Extremity & Spine
A 5-year-old child falls from monkey bars and sustains a completely displaced (Gartland Type III) extension-type supracondylar humerus fracture. On examination, the radial pulse is absent, but the hand is warm, pink, and has capillary refill under 2 seconds. What is the most appropriate next step in management?
. Immediate open exploration of the brachial artery
. CT angiography of the upper extremity
. Closed reduction and percutaneous pinning
. Observation and elevation of the arm
. Immediate fasciotomy of the forearm

Correct Answer & Explanation

. Closed reduction and percutaneous pinning

Explanation

In a 'pulseless, pink' hand associated with a supracondylar humerus fracture, the initial treatment is emergent closed reduction and percutaneous pinning. Often, the pulse returns once the fracture is reduced, and vascular exploration is not indicated unless the hand becomes cool and pale.

Question 5409

Topic: 4. Pediatrics

A 5-year-old boy presents with a completely displaced, extension-type supracondylar humerus fracture. Upon examination, his hand is pink and warm, but the radial pulse is absent. After urgent closed reduction and percutaneous pinning, the hand remains pink and well-perfused, but the radial pulse remains absent. What is the most appropriate next step in management?

. Immediate exploration of the brachial artery
. Intravenous heparin infusion
. Observation with admission for serial neurovascular checks
. Removal of pins and open reduction
. Arteriography of the upper extremity

Correct Answer & Explanation

. Observation with admission for serial neurovascular checks

Explanation

For a pulseless but well-perfused (pink and warm) hand following reduction and pinning of a pediatric supracondylar fracture, the standard of care is close observation. Collateral circulation is usually sufficient, and vascular exploration is only indicated if the hand becomes cold and ischemic.

Question 5410

Topic: Pediatric Hip

A 13-year-old obese boy presents with left thigh pain and a limp for 3 weeks. Examination reveals obligatory external rotation of the left hip with passive flexion. He is diagnosed with a slipped capital femoral epiphysis (SCFE). Which of the following is a strong indication for prophylactic pinning of the contralateral, asymptomatic hip?

. Age greater than 14 years
. Male gender
. Presence of an underlying endocrine disorder
. Body mass index > 95th percentile
. Acute on chronic presentation

Correct Answer & Explanation

. Presence of an underlying endocrine disorder

Explanation

Prophylactic pinning of the contralateral hip in SCFE is highly recommended for patients with underlying endocrine disorders (such as hypothyroidism or renal osteodystrophy) due to the exceedingly high risk of bilateral involvement. Routine prophylactic pinning in idiopathic cases remains controversial.

Question 5411

Topic: Pediatric Hip

A 13-year-old obese male presents with left knee pain and a limp. Radiographs reveal a slipped capital femoral epiphysis (SCFE). He undergoes in-situ percutaneous pinning. Which of the following factors places this patient at the highest risk for developing post-operative chondrolysis?

. Unrecognized initial severity of the slip
. Unrecognized pin penetration into the joint space
. The patient's elevated Body Mass Index (BMI)
. Delayed diagnosis of the condition
. An underlying endocrine abnormality

Correct Answer & Explanation

. Unrecognized pin penetration into the joint space

Explanation

Chondrolysis is a devastating complication of SCFE characterized by acute cartilage destruction. The most significant iatrogenic risk factor for chondrolysis is unrecognized pin penetration into the joint space during in-situ fixation. While severe slips and immobilization are also risk factors, intra-articular hardware strongly correlates with this complication.

Question 5412

Topic: Pediatric Hip

A 4-week-old female is diagnosed with developmental dysplasia of the hip (DDH) and is placed in a Pavlik harness. During a follow-up visit, the infant is noted to have a lack of active knee extension. Which specific harness misapplication is most likely responsible for this nerve palsy?

. Inadequate hip abduction
. Excessive hip hyperflexion
. Excessive hip hyperabduction
. Excessive hip extension
. Excessive internal rotation

Correct Answer & Explanation

. Excessive hip hyperflexion

Explanation

Excessive hip flexion (hyperflexion) in a Pavlik harness can compress the femoral nerve against the inguinal ligament, leading to a temporary femoral nerve palsy characterized by a lack of active knee extension. Excessive hip abduction places the infant at a higher risk for avascular necrosis (AVN) of the femoral head.

Question 5413

Topic: 4. Pediatrics
In the evaluation of a 7-year-old boy with Legg-Calvé-Perthes disease, the Catterall classification identifies 'head at risk' signs on plain radiography. Which of the following is one of these specific signs?
. Central pillar collapse
. Gage's sign
. Sagittal cleft
. Crescent sign
. Medial physeal closure

Correct Answer & Explanation

. Gage's sign

Explanation

Catterall's 'head at risk' signs indicate a worse prognosis in Legg-Calvé-Perthes disease. They include Gage's sign (a V-shaped radiolucency in the lateral portion of the epiphysis/adjacent metaphysis), lateral calcification, lateral subluxation of the femoral head, a horizontal physis, and a metaphyseal cyst.

Question 5414

Topic: Pediatric Upper Extremity & Spine
A 6-year-old girl falls onto an outstretched hand, sustaining a completely displaced, extension-type supracondylar humerus fracture (Gartland Type III). Which nerve is anatomically at the greatest risk of injury and most commonly injured in this specific fracture pattern?
. Radial nerve
. Ulnar nerve
. Anterior interosseous nerve (AIN)
. Posterior interosseous nerve (PIN)
. Musculocutaneous nerve

Correct Answer & Explanation

. Anterior interosseous nerve (AIN)

Explanation

In extension-type supracondylar humerus fractures, the proximal fragment is displaced anteriorly, placing the anterior interosseous nerve (AIN, a branch of the median nerve) at the highest risk. Clinically, this manifests as an inability to flex the IP joint of the thumb and the DIP joint of the index finger (a positive 'OK' sign test). Note: In flexion-type fractures, the ulnar nerve is more commonly injured.

Question 5415

Topic: Pediatric Hip

A 6-week-old female infant, born breech, undergoes a screening hip ultrasound. The alpha angle is measured at 45 degrees, and the beta angle is 80 degrees. What is the most appropriate next step in management?

. Reassurance and repeat ultrasound in 3 months
. Application of a Pavlik harness
. Closed reduction and spica casting
. Open reduction and capsulorrhaphy
. Application of an abduction brace for night use only

Correct Answer & Explanation

. Application of a Pavlik harness

Explanation

An alpha angle less than 60 degrees on a Graf ultrasound indicates developmental dysplasia of the hip (DDH). The standard initial treatment for a reducible dysplastic hip in an infant under 6 months is a Pavlik harness.

Question 5416

Topic: Pediatric Hip
In a 7-year-old boy diagnosed with Legg-Calvé-Perthes disease, which of the following radiographic findings constitutes the most significant prognostic factor for a poor outcome?
. Presence of a subchondral fracture (Crescent sign)
. Involvement of the medial pillar
. Lateral pillar involvement of greater than 50%
. Enlargement of the femoral head (coxa magna)
. Widening of the medial joint space

Correct Answer & Explanation

. Lateral pillar involvement of greater than 50%

Explanation

The Herring Lateral Pillar classification is the most reliable prognostic indicator for Legg-Calvé-Perthes disease. Group C (greater than 50% collapse of the lateral pillar) is highly predictive of a poor outcome.

Question 5417

Topic: Pediatric Hip

An infant treated with a Pavlik harness for developmental dysplasia of the hip (DDH) is noted to have decreased spontaneous active extension of the knee on the treated side. Which of the following is the most likely iatrogenic cause?

. Avascular necrosis of the femoral head
. Obturator nerve palsy from excessive abduction
. Femoral nerve palsy from excessive hyperflexion
. Sciatic nerve palsy from excessive internal rotation
. Inferior soft tissue impingement preventing relocation

Correct Answer & Explanation

. Femoral nerve palsy from excessive hyperflexion

Explanation

Femoral nerve palsy is a known complication of the Pavlik harness, typically caused by excessive hip hyperflexion compressing the nerve. It presents as an inability to actively extend the knee, and management involves adjusting the harness to reduce the degree of flexion.

Question 5418

Topic: Pediatric Hip
In the evaluation of a 7-year-old boy with Legg-Calvé-Perthes disease, the lateral pillar classification is used to predict outcome and guide management. During which radiographic stage of the disease should the lateral pillar classification be definitively determined?
. Initial (necrosis) stage
. Early fragmentation stage
. Late fragmentation stage
. Reossification stage
. Healed stage

Correct Answer & Explanation

. Early fragmentation stage

Explanation

The Herring lateral pillar classification evaluates the remaining height of the lateral pillar of the femoral head to accurately predict the long-term prognosis. It is most accurately and reliably assessed during the early fragmentation stage of the disease process.

Question 5419

Topic: Pediatric Hip

When evaluating a 6-week-old infant for developmental dysplasia of the hip (DDH) using the Graf ultrasound method, what anatomical landmark does the alpha angle evaluate, and what is considered a normal value?

. Cartilaginous roof; greater than 55 degrees
. Bony roof; greater than 60 degrees
. Cartilaginous roof; less than 43 degrees
. Bony roof; less than 50 degrees
. Labrum; greater than 60 degrees

Correct Answer & Explanation

. Bony roof; greater than 60 degrees

Explanation

The alpha angle measures the acetabular bony roof concavity relative to the ilium. An alpha angle greater than or equal to 60 degrees is considered normal (Graf Type I).

Question 5420

Topic: Pediatric Hip

The lateral pillar classification is crucial for determining the prognosis of Legg-Calve-Perthes disease. This classification evaluates the height of the lateral pillar of the capital femoral epiphysis on which specific radiographic view?

. Frog-leg lateral
. Cross-table lateral
. Anteroposterior (AP) pelvis
. False profile view
. Dunn view

Correct Answer & Explanation

. Anteroposterior (AP) pelvis

Explanation

The Herring lateral pillar classification relies on the AP pelvis radiograph during the fragmentation phase of the disease. It assesses the height of the lateral third of the epiphysis compared to the contralateral normal hip.

Test Yourself

Switch to an interactive, timed exam simulation to truly master this topic.

On this Page