Menu

Pediatric Hip MCQs

Practice Set 5 of 104

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

Question 81

Topic: Pediatric Hip

A 4-month-old female with developmental dysplasia of the hip is being treated with a Pavlik harness. During a follow-up visit, she is noted to have decreased active extension of the knee on the affected side. What is the most likely cause of this finding?

. Femoral nerve palsy due to excessive hyperflexion
. Sciatic nerve palsy from excessive abduction
. Obturator nerve palsy
. Avascular necrosis of the femoral head
. Patellar dislocation

Correct Answer & Explanation

. Femoral nerve palsy due to excessive hyperflexion

Explanation

Femoral nerve palsy is a known complication of Pavlik harness treatment caused by excessive hip flexion. The harness should be adjusted or temporarily discontinued until nerve function recovers.

Question 82

Topic: Pediatric Hip
An 8-year-old boy presents with a painless limp. Radiographs demonstrate fragmentation of the capital femoral epiphysis with lateral subluxation. According to the Herring lateral pillar classification, greater than 50% of the lateral pillar height is maintained. What is the classification and recommended treatment?
. Herring A; observation
. Herring B; containment surgery
. Herring C; containment surgery
. Herring B; spica cast
. Herring C; salvage osteotomy

Correct Answer & Explanation

. Herring B; containment surgery

Explanation

This describes a Herring B (lateral pillar >50% maintained) Legg-Calvé-Perthes disease. In children over 8 years old, containment surgery (e.g., femoral or pelvic osteotomy) yields significantly better outcomes than nonoperative treatment.

Question 83

Topic: Pediatric Hip

A 13-year-old obese male presents with acute on chronic left groin pain. Radiographs reveal a severe unstable slipped capital femoral epiphysis (SCFE). He undergoes in situ pinning. What is the most significant risk associated with an unstable SCFE compared to a stable one?

. Chondrolysis
. Avascular necrosis (AVN)
. Premature physeal closure
. Femoroacetabular impingement
. Slip progression

Correct Answer & Explanation

. Avascular necrosis (AVN)

Explanation

Unstable SCFE (defined as the inability to bear weight even with crutches) carries a much higher risk of AVN (up to 47%) compared to stable SCFE. Urgent decompression or careful positioning is debated, but AVN risk is definitively the most significant and devastating complication.

Question 84

Topic: Pediatric Hip
A 6-year-old boy presents with a painless limp. Radiographs demonstrate sclerosis and fragmentation of the capital femoral epiphysis. Which of the following is the most important prognostic factor in Legg-Calvé-Perthes disease?
. Age at clinical onset
. Gender of the patient
. Presence of a subchondral fracture line (crescent sign)
. Family history of the disease
. Initial range of motion

Correct Answer & Explanation

. Age at clinical onset

Explanation

Age at clinical onset is the single most important prognostic factor in Legg-Calvé-Perthes disease. Children who develop the disease before age 6 generally have a more favorable prognosis and greater potential for spherical remodeling.

Question 85

Topic: Pediatric Hip
Which of the following conditions is represented by this radiograph?
. Developmental dysplasia of the hip
. Juvenile rheumatoid arthritis
. Hemophilic arthropathy
. Legg-Calvé-Perthes disease
. Rickets

Correct Answer & Explanation

. Legg-Calvé-Perthes disease

Explanation

This patient has early fragmentation, epiphyseal flattening, metaphyseal lucency and widening, and sclerosis typical of patients with Legg-Calvé-Perthes disease in the early stages. In patients with juvenile rheumatoid arthritis, osteopenia and joint space narrowing are present, whereas in patients with developmental dysplasia, the acetabulum is shallow.

Question 86

Topic: Pediatric Hip

In which stage of Legg-Calva-Perthes disease is this patient:

. Initial
. Fragmentation
. Reossification
. Healed
. Degenerative

Correct Answer & Explanation

. Fragmentation

Explanation

This patient is in the end of the fragmentation phase of Legg-Calv-Perthes disease. Note the extreme flattening of the head and the lateral fragmentation.

Question 87

Topic: Pediatric Hip
All of the following conditions are indicated by this radiograph of a patient with Legg-Calvé-Perthes disease except:
. Coxa magna
. Coxa brevis
. Trochanteric overgrowth
. Coxa vara
. Coxa plana

Correct Answer & Explanation

. Coxa magna

Explanation

The hip of this patient with Legg-Calvé-Perthes disease has undergone epiphyseal flattening and premature (primarily lateral) physeal arrest. The femoral head has regrown with an enlarged width. The radiograph shows elements of coxa magna, coxa brevis, trochanteric overgrowth, and coxa plana. Coxa vara is not present.

Question 88

Topic: Pediatric Hip

A 5-year-old girl is evaluated for Legg-Calva-Perthes disease. She is in the fragmentation phase, and rotation is 10° internal and 15° external. Her epiphyseal extrusion index is 15%. Recommended treatment includes:

. Femoral osteotomy
. Iliac osteotomy
. Traction
. Shelf procedure
. Observation

Correct Answer & Explanation

. Observation

Explanation

The patients restricted range of motion is normal for a patient in the fragmentation phase of Legg-Calva-Perthe disease. The patiens degree of epiphyseal extrusion is not extreme. Observation is the most appropriate course of treatment.

Question 89

Topic: Pediatric Hip

What is the risk of hip arthroplasty for 50-year-old patients with Legg-C alva-Perthes disease:

. 10%
. 25%
. 33%
. 50%
. 75%

Correct Answer & Explanation

. 50%

Explanation

Long-term study has shown that 50% of 50-year-old patients with Legg-C alva-Perthes disease will have degenerative changes in their hips significant enough to make them candidates for hip arthroplasty.

Question 90

Topic: Pediatric Hip

A 13-year-old obese boy presents with right knee pain and an obligate external rotation of the hip during passive flexion. Radiographs show a "trellis" sign and Klein's line not intersecting the lateral epiphysis. What is the most appropriate initial treatment?

. Spica casting
. In situ single screw fixation
. Closed reduction and internal fixation
. Proximal femoral osteotomy
. Observation with protected weight-bearing

Correct Answer & Explanation

. In situ single screw fixation

Explanation

The clinical presentation and radiographic findings are classic for Slipped Capital Femoral Epiphysis (SCFE). The standard initial treatment is in situ fixation with a single cannulated screw.

Question 91

Topic: Pediatric Hip

In a 7-year-old boy diagnosed with Legg-Calve-Perthes disease, which of the following radiographic findings represents a "head at risk" sign indicating a poorer prognosis?

. Medial subluxation of the femoral head
. Gage sign
. Decreased medial joint space
. Intact lateral pillar
. Metaphyseal sclerosis

Correct Answer & Explanation

. Gage sign

Explanation

Catterall's "head at risk" signs include lateral subluxation, Gage sign (V-shaped defect in the lateral epiphysis), calcification lateral to the epiphysis, and horizontal growth plate.

Question 92

Topic: Pediatric Hip

A 4-week-old female infant has a positive Ortolani test on the left side. Ultrasound shows an alpha angle of 40 degrees. What is the most appropriate next step in management?

. Triple pelvic osteotomy
. Closed reduction and spica casting
. Pavlik harness application
. Observation with repeat ultrasound in 4 weeks
. Open reduction

Correct Answer & Explanation

. Pavlik harness application

Explanation

A positive Ortolani test with an alpha angle < 60 degrees indicates a dislocated but reducible hip. The Pavlik harness is the gold standard initial treatment for DDH in infants under 6 months.

Question 93

Topic: Pediatric Hip

A 4-month-old female is treated with a Pavlik harness for developmental dysplasia of the hip (DDH). At her follow-up appointment, the parents report she is not kicking her right leg as much as the left. Which of the following nerve palsies is the most common complication of excessive hip flexion in a Pavlik harness?

. Sciatic nerve
. Obturator nerve
. Femoral nerve
. Superior gluteal nerve
. Pudendal nerve

Correct Answer & Explanation

. Femoral nerve

Explanation

Femoral nerve palsy is the most common nerve injury associated with the Pavlik harness, typically caused by excessive hip flexion. Excessive abduction, conversely, increases the risk of avascular necrosis of the femoral head.

Question 94

Topic: Pediatric Hip

A 13-year-old obese male presents with left knee pain and a limp. Examination reveals obligate external rotation of the hip with passive flexion. Radiographs confirm a slipped capital femoral epiphysis (SCFE). Which of the following best describes the anatomical displacement of the femoral neck relative to the epiphysis?

. Anterior and Superior
. Anterior and Inferior
. Posterior and Superior
. Posterior and Inferior
. Medial and Inferior

Correct Answer & Explanation

. Posterior and Inferior

Explanation

In SCFE, the epiphysis remains seated within the acetabulum while the femoral neck displaces anteriorly and superiorly. Radiographically, the epiphysis appears to have slipped posteriorly and inferiorly.

Question 95

Topic: Pediatric Hip
During the progression of Legg-Calvé-Perthes disease, which radiographic sign represents a subchondral fracture and typically heralds the onset of the fragmentation stage?
. Gage sign
. Crescent sign
. Sagging rope sign
. Trethowan sign
. Waldenström sign

Correct Answer & Explanation

. Crescent sign

Explanation

The crescent sign represents a subchondral fracture of the femoral head. It usually indicates the transition from the initial avascular necrosis phase to the fragmentation stage in Legg-Calvé-Perthes disease.

Question 96

Topic: Pediatric Hip
In a child diagnosed with Legg-Calvé-Perthes disease, which of the following factors has been shown to be the most significant prognostic indicator for the long-term anatomic outcome of the hip?
. Gender of the patient
. Age of the patient at the onset of symptoms
. Body mass index
. Family history of hip dysplasia
. Duration of the initial limp

Correct Answer & Explanation

. Age of the patient at the onset of symptoms

Explanation

Age at the onset of Legg-Calvé-Perthes disease is the most critical prognostic factor. Children who develop the disease before 6 to 8 years of age have a significantly better prognosis due to the greater remaining growth potential for femoral head remodeling.

Question 97

Topic: Pediatric Hip

A 13-year-old obese boy presents with acute knee pain and inability to bear weight. Radiographs show a severe acute-on-chronic slipped capital femoral epiphysis (SCFE). Which of the following is the most devastating potential complication of forceful anatomic reduction of the slip prior to fixation?

. Chondrolysis
. Avascular necrosis (AVN) of the femoral head
. Premature closure of the triradiate cartilage
. Cam-type femoroacetabular impingement
. Slipped capital femoral epiphysis of the contralateral hip

Correct Answer & Explanation

. Avascular necrosis (AVN) of the femoral head

Explanation

Forceful reduction of a displaced SCFE significantly stretches or tears the delicate epiphyseal blood supply (retinacular vessels), dramatically increasing the risk of avascular necrosis (AVN). In situ pinning is generally preferred to minimize this risk.

Question 98

Topic: Pediatric Hip
A 13-year-old boy who underwent in situ fixation of slipped capital femoral epiphysis 1 year ago calls your office to complain of knee pain on the other side. He is able to bear his weight on the leg. You recommend:
. No sports for 1 month and an office visit if the symptoms continue
. An office visit within the next 2 weeks for evaluation
. Crutches and an office visit within 24 hours
. Magnetic resonance image of the knee and an office visit if the results are abnormal
. Arthroscopy of the knee

Correct Answer & Explanation

. Crutches and an office visit within 24 hours

Explanation

This patient most likely has a contralateral slipped capital femoral epiphysis. It may even be in the "preslip" category. Acute progression to an unstable slip is possible at any time and may lead to avascular necrosis and permanent loss of motion. Therefore, urgent examination with physical examination and plain radiographs is necessary.

Question 99

Topic: Pediatric Hip

A 6-month-old infant with developmental dysplasia of the hip (DDH) is being evaluated for closed reduction. A pre-procedural arthrogram demonstrates an "hourglass" constriction of the capsule. Which anatomical structure is responsible for this constriction?

. Ligamentum teres
. Transverse acetabular ligament
. Iliopsoas tendon
. Reflected head of the rectus femoris
. Gluteus medius tendon

Correct Answer & Explanation

. Iliopsoas tendon

Explanation

In long-standing DDH, the capsular constriction that creates the classic "hourglass" appearance on arthrography is caused by the tight iliopsoas tendon crossing over the anterior capsule.

Question 100

Topic: Pediatric Hip

A 13-year-old girl with renal osteodystrophy undergoes surgical pinning for a severe left Slipped Capital Femoral Epiphysis (SCFE). What is the primary indication for prophylactic pinning of her contralateral asymptomatic hip?

. Her chronologic age over 12 years
. Her underlying endocrinopathy and metabolic disorder
. The severe grade of the left-sided slip
. Her female gender
. The presence of a metaphyseal blanch sign on the right

Correct Answer & Explanation

. Her underlying endocrinopathy and metabolic disorder

Explanation

Prophylactic pinning of the contralateral hip is highly indicated in patients with SCFE associated with endocrine or metabolic disorders (e.g., renal osteodystrophy, hypothyroidism). These conditions carry a near 100% risk of eventual bilateral involvement.

Test Yourself

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

On this Page