Menu

Pediatric Upper Extremity & Spine MCQs

Practice Set 6 of 33

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

Question 101

Topic: Pediatric Upper Extremity & Spine
A 13-year-old premenarchal female presents with a 35-degree right main thoracic adolescent idiopathic scoliosis. Hand radiographs indicate she is at Sanders Skeletal Maturity Stage 3. What is the most evidence-based management strategy to prevent progression to surgery?
. Observation with radiographs every 6 months
. Thoracolumbosacral orthosis (TLSO) bracing for at least 18 hours per day
. Nighttime-only bending brace
. Anterior vertebral body tethering (VBT)
. Posterior spinal fusion with pedicle screws

Correct Answer & Explanation

. Thoracolumbosacral orthosis (TLSO) bracing for at least 18 hours per day

Explanation

The BRAIST trial demonstrated that TLSO bracing significantly decreases the rate of curve progression to the surgical threshold (50 degrees) in immature patients (Sanders 2-3, Risser 0-2) with curves of 20-40 degrees. The effect is highly dose-dependent, with optimal results seen with >18 hours of daily wear.

Question 102

Topic: Pediatric Upper Extremity & Spine

According to the Lenke classification for adolescent idiopathic scoliosis, a curve pattern consisting of a structural main thoracic curve and a structural proximal thoracic curve, accompanied by a non-structural lumbar curve, is classified as which type?

. Lenke 1
. Lenke 2
. Lenke 3
. Lenke 4
. Lenke 5

Correct Answer & Explanation

. Lenke 2

Explanation

A Lenke 2 curve is a "Double Thoracic" pattern, characterized by structural proximal thoracic and main thoracic curves, with a non-structural lumbar curve. A Lenke 1 is a main thoracic curve only.

Question 103

Topic: Pediatric Upper Extremity & Spine

A 15-year-old female is undergoing a posterior spinal fusion for adolescent idiopathic scoliosis (Lenke 1A). During the derotation maneuver, the neurophysiologist reports a sudden loss of motor evoked potentials (MEPs) in the bilateral lower extremities, while somatosensory evoked potentials (SSEPs) remain stable. What is the most appropriate initial management step?

. Administer a bolus of intravenous methylprednisolone
. Perform a wake-up test immediately
. Increase mean arterial pressure (MAP) to > 90 mmHg and release the deformity correction
. Order an intraoperative MRI to assess for epidural hematoma
. Proceed with the surgery as stable SSEPs indicate an intact posterior column

Correct Answer & Explanation

. Increase mean arterial pressure (MAP) to > 90 mmHg and release the deformity correction

Explanation

Loss of MEPs with intact SSEPs suggests anterior spinal cord ischemia. The immediate algorithm involves increasing the MAP to optimize cord perfusion and releasing the surgical correction or hardware that precipitated the change.

Question 104

Topic: Pediatric Upper Extremity & Spine

In the Lenke classification system for adolescent idiopathic scoliosis, a minor curve is defined as non-structural based on its flexibility on side-bending radiographs. What is the specific Cobb angle threshold on a side-bending radiograph that defines a curve as non-structural?

. Reduces to < 10 degrees
. Reduces to < 15 degrees
. Reduces to < 20 degrees
. Reduces to < 25 degrees
. Reduces to < 30 degrees

Correct Answer & Explanation

. Reduces to < 25 degrees

Explanation

In the Lenke classification, a minor curve is considered non-structural if it reduces to less than 25 degrees on supine maximum voluntary side-bending radiographs. Curves that remain 25 degrees or greater are considered structural.

Question 105

Topic: Pediatric Upper Extremity & Spine
According to the results of the Bracing in Adolescent Idiopathic Scoliosis Trial (BRAIST), which of the following factors was most significantly correlated with the successful prevention of curve progression to the surgical threshold?
. The type of brace utilized (Boston vs. Charleston)
. The patient's initial Risser stage
. The amount of in-brace curve correction achieved
. The duration of brace wear exceeding 18 hours per day
. The patient's body mass index (BMI)

Correct Answer & Explanation

. The duration of brace wear exceeding 18 hours per day

Explanation

The BRAIST trial demonstrated a significant dose-response relationship between hours of brace wear and success rate. Wearing the brace for more than 18 hours per day was highly correlated with preventing curve progression to the surgical threshold (>50 degrees).

Question 106

Topic: Pediatric Upper Extremity & Spine

A 12-year-old girl is diagnosed with adolescent idiopathic scoliosis (AIS). She has not yet reached menarche. Which of the following radiographic findings indicates the highest risk for curve progression?

. Risser stage 4
. Closed triradiate cartilage
. Open triradiate cartilage
. Nash-Moe grade I rotation
. Cobb angle of 15 degrees

Correct Answer & Explanation

. Open triradiate cartilage

Explanation

Open triradiate cartilage indicates the patient is in the peak height velocity phase of growth, which corresponds to the highest risk of curve progression in AIS. The triradiate cartilage typically closes right around or shortly after peak height velocity.

Question 107

Topic: Pediatric Upper Extremity & Spine
In the Lenke classification system for adolescent idiopathic scoliosis (AIS), a minor curve is defined as 'structural' and should be included in the fusion construct if:
. It does not correct to less than 25 degrees on side-bending radiographs.
. It does not correct to less than 10 degrees on side-bending radiographs.
. It has a Nash-Moe rotation of grade III.
. The patient has a Risser stage of 0.
. It is accompanied by a positive sagittal vertical axis (SVA).

Correct Answer & Explanation

. It does not correct to less than 25 degrees on side-bending radiographs.

Explanation

According to the Lenke classification, a minor curve is deemed structural if it remains 25 degrees or greater on supine maximum side-bending radiographs, or if there is regional kyphosis of 20 degrees or more.

Question 108

Topic: Pediatric Upper Extremity & Spine

A 13-year-old girl with adolescent idiopathic scoliosis (AIS) has a right thoracic curve of 34 degrees. She is pre-menarchal and Risser stage 0. What is the most appropriate management?

. Observation with radiographs every 6 months
. Full-time TLSO bracing
. Nighttime-only Providence bracing
. Posterior spinal fusion
. Anterior vertebral body tethering

Correct Answer & Explanation

. Full-time TLSO bracing

Explanation

For an immature patient (Risser 0-2) with a curve between 25 and 40 degrees, TLSO bracing for a minimum of 16-18 hours a day is the gold standard to prevent progression to surgical magnitude.

Question 109

Topic: Pediatric Upper Extremity & Spine

A 25-year-old male sustains a C5 burst fracture with significant retropulsion into the spinal canal after a diving accident. On initial assessment, he has complete paralysis below the C5 level, including absent motor and sensory function in the bilateral upper and lower extremities, and absent sacral sparing. Which ASIA Impairment Scale (AIS) grade best describes his neurological status?

. AIS A
. AIS B
. AIS C
. AIS D
. AIS E

Correct Answer & Explanation

. AIS A

Explanation

Correct Answer: ARationale:The ASIA Impairment Scale (AIS) is used to classify the severity of spinal cord injury. AIS A is defined as a complete spinal cord injury, characterized by no motor or sensory function preserved in the sacral segments S4-S5. The patient's description of 'complete paralysis below the C5 level, including absent motor and sensory function in the bilateral upper and lower extremities, and absent sacral sparing' directly corresponds to the definition of AIS A.Why other options are incorrect:B) AIS B:Incomplete injury with sensory but not motor function preserved below the neurological level and extending through the sacral segments S4-S5.C) AIS C:Incomplete injury with motor function preserved below the neurological level, and more than half of key muscles below the neurological level have a muscle grade less than 3.D) AIS D:Incomplete injury with motor function preserved below the neurological level, and at least half of key muscles below the neurological level have a muscle grade of 3 or greater.E) AIS E:Normal motor and sensory function.

Question 110

Topic: Pediatric Upper Extremity & Spine

A 13-year-old female with adolescent idiopathic scoliosis presents with a right thoracic curve measuring 48 degrees. Her Risser stage is 1. What is the most appropriate management?

. Observation with repeat radiographs in 6 months
. Thoracolumbosacral orthosis (TLSO) bracing for 23 hours/day
. Posterior spinal fusion
. Anterior vertebral body tethering
. Physiotherapy and core strengthening

Correct Answer & Explanation

. Posterior spinal fusion

Explanation

In a highly skeletally immature patient (Risser 1) with a curve greater than 45-50 degrees, the risk of progression is extreme. Posterior spinal fusion is the standard of care to correct the deformity, as bracing is generally ineffective for curves >45 degrees.

Question 111

Topic: Pediatric Upper Extremity & Spine
A 9-year-old child presents with a Gartland Type III supracondylar humerus fracture, displaced posteromedially. During closed reduction, which of the following maneuvers is most critical for correcting the rotational component of this specific fracture pattern?
. Applying valgus stress to the elbow.
. Maintaining the forearm in supination.
. Pronating the forearm.
. Applying varus stress to the elbow.
. Hyperflexing the elbow beyond 120 degrees.

Correct Answer & Explanation

. Pronating the forearm.

Explanation

For posteromedial displacement, pronate the forearm. For posterolateral displacement, supinate the forearm. The common Type III extension fracture with posteromedial displacement often requires pronation to disengage the radial column.

Question 112

Topic: Pediatric Upper Extremity & Spine

A 5-year-old child is recovering from a successfully pinned Gartland Type II supracondylar humerus fracture. K-wires were removed at 3 weeks post-operatively. Which of the following is the most appropriate recommendation for the initial phase of rehabilitation?

. Initiate aggressive passive stretching of the elbow to regain full extension.
. Encourage gentle active range of motion (AROM) exercises for the elbow and wrist.
. Begin immediate weight-bearing activities to strengthen the arm.
. Maintain strict immobilization in a cast for an additional 3 weeks.
. Refer for immediate occupational therapy focusing on fine motor skills.

Correct Answer & Explanation

. Encourage gentle active range of motion (AROM) exercises for the elbow and wrist.

Explanation

Correct Answer: BThe 'Post-Operative Rehabilitation Protocols' section for Supracondylar Humerus Fracture (Pinned) states: 'After pin removal, a posterior splint may be used for comfort, but active range of motion of the elbow and wrist is immediately encouraged. Crucial: Avoid forceful passive stretching or manipulation of the elbow joint, as this can increase the risk of heterotopic ossification and myositis ossificans. Gravity-assisted gentle flexion/extension exercises.'Option A (Initiate aggressive passive stretching of the elbow to regain full extension):This is explicitly warned against in the text due to the risk of heterotopic ossification and myositis ossificans.Option B (Encourage gentle active range of motion (AROM) exercises for the elbow and wrist):This is the correct and recommended approach for early rehabilitation after pin removal, as it helps restore motion without the risks associated with passive stretching.Option C (Begin immediate weight-bearing activities to strengthen the arm):Weight-bearing and strengthening exercises are part of a later phase of rehabilitation (4-8+ weeks), not immediately after pin removal.Option D (Maintain strict immobilization in a cast for an additional 3 weeks):K-wires are typically removed when early callus formation is evident (around 3-4 weeks), and at that point, active motion is encouraged, not continued strict immobilization.Option E (Refer for immediate occupational therapy focusing on fine motor skills):While occupational therapy may be beneficial, the immediate focus after pin removal for an elbow fracture is on regaining elbow and wrist range of motion, not primarily fine motor skills, unless there are specific neurological deficits.

Question 113

Topic: Pediatric Upper Extremity & Spine
Based on the physical examination findings of the 15-year-old male (sensation not intact distal to the umbilicus, no sensation around the rectum, no voluntary rectal tone, 0/5 strength in bilateral lower extremities, and an intact bulbocavernosus reflex), what would be the patient’s classification according to the American Spinal Injury Association (ASIA) impairment scale?
. A
. B
. C
. D
. E

Correct Answer & Explanation

. A

Explanation

The patient presents with complete motor and sensory loss below the level of the umbilicus, including the sacral segments S4-5 (no sensation around the rectum and no voluntary rectal tone). According to the ASIA classification, AIS A (Complete) indicates no sensory or motor function is preserved in the sacral segments S4–5.

Question 114

Topic: Pediatric Upper Extremity & Spine

A newborn is evaluated for a unilateral absent thumb and marked radial deviation of the wrist. Radiographs confirm radial longitudinal deficiency (radial clubhand). Which of the following tests is most critical to perform before any surgical intervention?

. Chromosomal breakage testing
. Serum lead levels
. Electromyography of the upper extremity
. Sweat chloride test
. Karyotype analysis for Trisomy 21

Correct Answer & Explanation

. Chromosomal breakage testing

Explanation

Radial longitudinal deficiency is highly associated with systemic syndromes, most notably Fanconi anemia. Chromosomal breakage testing is critical because Fanconi anemia carries a high risk of fatal aplastic anemia and necessitates specific perioperative and long-term medical management.

Question 115

Topic: Pediatric Upper Extremity & Spine
A 6-year-old boy sustains an extension-type Gartland III supracondylar humerus fracture. Post-reduction, he is unable to flex the interphalangeal joint of his thumb and the distal interphalangeal joint of his index finger. Which nerve is most likely injured?
. Ulnar nerve
. Posterior interosseous nerve
. Anterior interosseous nerve
. Superficial radial nerve
. Recurrent motor branch of the median nerve

Correct Answer & Explanation

. Anterior interosseous nerve

Explanation

The anterior interosseous nerve (AIN) is the most commonly injured nerve in extension-type supracondylar humerus fractures. It presents clinically as an inability to make the "OK" sign due to weakness of the FPL and the FDP to the index finger.

Question 116

Topic: Pediatric Upper Extremity & Spine
A 5-year-old boy presents with a displaced Gartland III supracondylar humerus fracture. The hand is pink but the radial pulse is absent. After closed reduction and percutaneous pinning, the hand remains pink and well-perfused with a capillary refill of 2 seconds, but the radial pulse remains unpalpable. What is the most appropriate next step?
. Immediate open vascular exploration via an anterior approach
. Observation and hospital admission for serial neurovascular checks
. Administration of intra-arterial vasodilators
. Removal of pins and transition to open reduction
. Immediate CT angiography of the upper extremity

Correct Answer & Explanation

. Observation and hospital admission for serial neurovascular checks

Explanation

A "pink, pulseless" hand after anatomic reduction and pinning of a supracondylar humerus fracture generally indicates adequate collateral perfusion. The standard of care is close observation and admission for serial clinical checks rather than immediate vascular exploration.

Question 117

Topic: Pediatric Upper Extremity & Spine

A 6-year-old boy falls on an outstretched hand and sustains an extension-type supracondylar humerus fracture. Upon examination, he cannot actively flex the interphalangeal joint of his thumb. Which nerve is most likely injured?

. Ulnar nerve
. Radial nerve
. Posterior interosseous nerve
. Anterior interosseous nerve
. Musculocutaneous nerve

Correct Answer & Explanation

. Anterior interosseous nerve

Explanation

The anterior interosseous nerve (AIN) is the most commonly injured nerve in extension-type supracondylar humerus fractures. AIN palsy presents with the inability to flex the IP joint of the thumb (flexor pollicis longus) and the distal IP joint of the index finger (flexor digitorum profundus), preventing the "A-OK" sign.

Question 118

Topic: Pediatric Upper Extremity & Spine

A 5-year-old girl falls on an outstretched hand and sustains a Milch Type II lateral condyle fracture of the humerus with 3 mm of displacement. What is the standard management for this injury?

. Long arm cast in supination for 4 weeks
. Closed reduction and percutaneous pinning (CRPP)
. Open reduction and internal fixation (ORIF)
. Excision of the fragment and lateral collateral ligament repair
. Non-weight bearing in a sling

Correct Answer & Explanation

. Open reduction and internal fixation (ORIF)

Explanation

Pediatric lateral condyle fractures displaced more than 2 mm generally require open reduction and internal fixation (ORIF). Closed reduction is often inadequate due to soft tissue interposition and rotation, carrying a high risk of nonunion.

Question 119

Topic: Pediatric Upper Extremity & Spine
A 6-year-old boy falls from monkey bars and sustains a displaced extension-type supracondylar humerus fracture (Gartland Type III). On physical examination, he is unable to flex the interphalangeal joint of his thumb and the distal interphalangeal joint of his index finger. Which nerve is most likely injured?
. Radial nerve
. Ulnar nerve
. Anterior interosseous nerve
. Posterior interosseous nerve
. Musculocutaneous nerve

Correct Answer & Explanation

. Anterior interosseous nerve

Explanation

The anterior interosseous nerve (AIN) is the most commonly injured nerve in extension-type supracondylar humerus fractures. Injury leads to an inability to make the "A-OK" sign due to paralysis of the flexor pollicis longus and the flexor digitorum profundus to the index finger.

Question 120

Topic: Pediatric Upper Extremity & Spine

A 14-year-old female patient with adolescent idiopathic scoliosis (AIS) has a 35-degree right thoracic curve. She is premenarchal and has a Risser sign of 0. Based on the natural history of AIS, which of the following factors is the strongest indicator of a high likelihood of curve progression?

. Her female gender, as females are more prone to scoliosis.
. The curve magnitude of 35 degrees, classifying it as a moderate curve.
. Her premenarchal status and Risser 0, indicating significant skeletal immaturity.
. The right thoracic location of the curve, which is the most common pattern.
. The absence of severe back pain, suggesting a typical idiopathic presentation.

Correct Answer & Explanation

. Her premenarchal status and Risser 0, indicating significant skeletal immaturity.

Explanation

Correct Answer: CThe case states that 'The development and progression of scoliosis is related to skeletal growth, typically deteriorating most rapidly during the adolescent growth spurt. Features that indicate an increased likelihood of curve progression are therefore associated with but not limited to immaturity. They are: Young age at onset, Premenarchal status, Physical immaturity, Large curves, Female gender.' Premenarchal status combined with a Risser 0 indicates significant skeletal immaturity, meaning the patient has substantial growth remaining. This period of rapid growth is when curves are most likely to progress rapidly.Option A is incorrectbecause while female gender is a risk factor for progression (5.4:1 female to male for curves >20 degrees), skeletal immaturity (premenarchal, Risser 0) is a more direct and stronger predictor ofrapidprogression due to remaining growth potential.Option B is incorrectbecause a 35-degree curve is indeed moderate, and larger curves have a greater potential for progression. However, therateof progression is most strongly linked to the amount of remaining growth, which is best indicated by skeletal immaturity markers like premenarchal status and Risser 0.Option D is incorrectbecause a right thoracic curve is the most common pattern for AIS, but the location itself does not inherently indicate a higher likelihood of progression compared to other factors like skeletal maturity. Atypical curves (e.g., left thoracic) might suggest underlying pathology, but a typical right thoracic curve doesn't predict progression rate.Option E is incorrectbecause the absence of severe back pain is a typical feature of AIS and does not indicate a higher likelihood of progression. Severe pain would, in fact, be an 'atypical feature' suggesting possible underlying pathology, not a predictor of progression in typical AIS.

Test Yourself

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

On this Page