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 1321
Topic: Pediatric Hip
A 28-year-old female with a history of a skeletal dysplasia presents with hip pain. Her pelvic radiograph is shown below. What is the primary deformity seen in the proximal femur that typically develops in this condition?
Correct Answer & Explanation
. Coxa vara
Explanation
Correct Answer: Coxa varaThe radiograph demonstrates retarded ossification of the proximal femur, which is usually accompanied by coxa vara in older patients with spondyloepiphyseal dysplasia.
Question 1322
Topic: Pediatric Hip
A 28-year-old female with a history of spondyloepiphyseal dysplasia presents with hip pain and a waddling gait. Her pelvic radiograph is shown below. Which of the following proximal femoral deformities is most commonly associated with this condition in adulthood?
Correct Answer & Explanation
. Coxa vara
Explanation
Correct Answer: BThe radiograph shows retarded ossification of the proximal femur, which is usually accompanied by coxa vara in the elderly period or adulthood in patients with spondyloepiphyseal dysplasia. This deformity contributes to the waddling gait and progressive arthropathy seen in these patients.
Question 1323
Topic: Pediatric Hip
A 28-year-old female with a known history of an inherited chondrodysplasia presents with hip pain and a waddling gait. Her pelvic radiograph is shown below. Which of the following deformities is most commonly associated with the delayed ossification of the proximal femur seen in this condition?
Correct Answer & Explanation
. Coxa vara
Explanation
Correct Answer: Coxa varaIn Spondyloepiphyseal Dysplasia, there is retarded ossification of the proximal femur in young patients, which is usually accompanied by the development of coxa vara in the older period, as seen on the radiograph of this 28-year-old female. This contributes to the progressive arthropathy and gait abnormalities.
Question 1324
Topic: Pediatric Hip
A 28-year-old female with a known skeletal dysplasia presents with hip pain. Her pelvic radiograph is shown below.
Which of the following best describes the characteristic proximal femoral deformity seen in this condition during adulthood?
Correct Answer & Explanation
. Coxa vara with retarded ossification of the proximal femur
Explanation
Correct Answer: Coxa vara with retarded ossification of the proximal femurIn Spondyloepiphyseal dysplasia, there is retarded ossification of the proximal femur in youth, which typically progresses to coxa vara in adulthood, as demonstrated in the provided radiograph.
Question 1325
Topic: Pediatric Hip
A patient with spondyloepiphyseal dysplasia congenita is noted to have severe, progressive coxa vara. If surgical intervention is planned, what is the primary goal of the recommended procedure?
Correct Answer & Explanation
. To perform a subtrochanteric valgus producing osteotomy
Explanation
Coxa vara is a hallmark of SEDC due to delayed ossification of the femoral neck. A subtrochanteric valgus osteotomy is indicated to correct the neck-shaft angle, improve abductor mechanics, and promote ossification of the femoral neck.
Question 1326
Topic: Pediatric Hip
Spondyloepiphyseal dysplasia (SED) can present similarly to Morquio syndrome. Which of the following clinical features most reliably distinguishes SED congenita from Morquio syndrome?
Correct Answer & Explanation
. Absence of corneal clouding and normal mucopolysaccharides
Explanation
Both conditions feature short trunk dwarfism, platyspondyly, and odontoid hypoplasia. However, Morquio syndrome is a mucopolysaccharidosis characterized by keratan sulfate excretion and corneal clouding, which are absent in SEDC.
Question 1327
Topic: Pediatric Hip
A 6-year-old boy with Spondyloepiphyseal Dysplasia Congenita is noted to have a progressively worsening waddling gait. Pelvic radiographs reveal bilateral coxa vara with a Hilgenreiner-epiphyseal angle (HEA) of 65 degrees. What is the most appropriate management?
Correct Answer & Explanation
. Valgus-producing proximal femoral osteotomy
Explanation
In children with SED Congenita, progressive coxa vara with a Hilgenreiner-epiphyseal angle greater than 60 degrees is an indication for a valgus-producing subtrochanteric osteotomy. This converts shear forces into compressive forces, promoting healing and preventing nonunion.
Question 1328
Topic: Pediatric Hip
Which of the following clinical features most reliably differentiates Spondyloepiphyseal Dysplasia Congenita (SEDC) from Morquio syndrome (Mucopolysaccharidosis Type IV) in a 6-year-old patient with short-trunk dwarfism and atlantoaxial instability?
Correct Answer & Explanation
. Presence of corneal clouding
Explanation
While both SEDC and Morquio syndrome present with short-trunk dwarfism, coxa vara, and odontoid hypoplasia, Morquio syndrome features corneal clouding and normal intelligence. SEDC involves myopia and retinal detachments but lacks corneal clouding.
Question 1329
Topic: Pediatric Hip
A 4-year-old boy with a known COL2A1 mutation is being evaluated in the orthopedic clinic for a waddling gait.
Based on the typical natural history of his skeletal dysplasia, which of the following hip deformities is most likely present?
Correct Answer & Explanation
. Progressive coxa vara
Explanation
Spondyloepiphyseal dysplasia congenita (SEDC) frequently involves delayed ossification of the femoral head and neck, leading to progressive coxa vara. This often requires corrective proximal femoral valgus osteotomy to improve hip mechanics and gait.
Question 1330
Topic: Pediatric Hip
A 6-month-old infant is diagnosed with developmental dysplasia of the hip (DDH) after a positive Barlow test and limited abduction on clinical examination, confirmed by ultrasound showing a dislocated hip (Graf type IV). What is the most appropriate initial treatment?
Correct Answer & Explanation
. Pavlik harness application
Explanation
For infants aged 0-6 months with a dislocatable or dislocated hip (Graf type IIc or worse), a Pavlik harness is the gold standard initial treatment. It maintains the hip in flexion and abduction, promoting concentric reduction and acetabular development. Double diapering is ineffective. Spica cast or open reduction is reserved for harness failures or older infants/children where the harness is no longer effective.
Question 1331
Topic: Pediatric Hip
Which of the following describes the 'UnPappy' clinical sign in the context of developmental dysplasia of the hip (DDH)?
Correct Answer & Explanation
. Asymmetry of gluteal folds
Explanation
Asymmetry of the gluteal (or thigh) folds is often referred to as a 'Pappy' sign, or simply gluteal fold asymmetry. It is an indirect sign of DDH and indicates tightness of adductor muscles or shortening of the thigh, but it is not a direct diagnostic maneuver for hip instability. Limited hip abduction is a more specific and consistent clinical finding. Ortolani and Barlow tests are direct tests for hip stability. Galeazzi sign is apparent leg length discrepancy due to hip dislocation.
Question 1332
Topic: Pediatric Hip
A 4-year-old child presents with a painless limp and thigh atrophy. Radiographs show increased density and fragmentation of the femoral head epiphysis. What is the most appropriate initial management?
Correct Answer & Explanation
. Containment methods such as bracing or abduction osteotomy
Explanation
The clinical presentation and radiographic findings are consistent with Legg-Calvé-Perthes disease. The primary goal of management is containment of the femoral head within the acetabulum to maintain its spherical shape during revascularization and remodeling, thereby preventing collapse and promoting a better long-term outcome. This is achieved through various containment methods, including bracing (e.g., Scottish Rite brace) or surgical osteotomies (femoral or pelvic) for specific age groups and stages of the disease, depending on the severity of involvement. Non-weight-bearing alone is generally insufficient as a definitive treatment in most cases, and physical therapy is an adjunct, not primary treatment for containment.
Question 1333
Topic: Pediatric Hip
A 1-year-old child presents with a limp, and a 'waddling' gait. Physical examination reveals limited hip abduction and internal rotation bilaterally, and an exaggerated lumbar lordosis. Radiographs show bilateral hip dislocations. What is the most likely diagnosis?
Correct Answer & Explanation
. Developmental dysplasia of the hip (DDH)
Explanation
The clinical presentation (limp, waddling gait, limited abduction/internal rotation, exaggerated lumbar lordosis to compensate for dislocated hips) and radiographic findings (bilateral hip dislocations) in a 1-year-old are highly suggestive of developmental dysplasia of the hip (DDH). At this age, the dislocations are often fixed, and the typical newborn clinical tests may no longer be positive. SCFE and Perthes are conditions of older children. Cerebral palsy could cause gait abnormalities, but primary bilateral hip dislocation is more indicative of DDH. Transient synovitis is acute and self-limiting.
Question 1334
Topic: Pediatric Hip
A 48-year-old female with Crowe Type IV developmental dysplasia of the hip (DDH) undergoes total hip arthroplasty. The surgeon plans to bring the acetabulum to the true anatomical hip center to restore biomechanics and leg length. What is a specific major intraoperative challenge or potential postoperative complication associated with this strategy in Crowe Type IV DDH?
Correct Answer & Explanation
. High risk of sciatic nerve palsy due to excessive limb lengthening
Explanation
In Crowe Type IV DDH, the femoral head is significantly displaced superiorly, leading to a chronically shortened limb. Reconstructing the hip at the true anatomical center can require substantial lengthening of the limb, often exceeding 4 cm. This significant lengthening can put the sciatic nerve under extreme tension, leading to a high risk of sciatic nerve palsy, which can be devastating. Intraoperative neuromonitoring, sequential lengthening, and careful soft tissue releases (e.g., adductor tenotomy, psoas release, femoral shortening osteotomy) are often employed to mitigate this risk. Femoral nerve palsy is less common with posterior approaches but can occur with anterior retraction. Heterotopic ossification is a general risk but not specific to limb lengthening. Acetabular stability is a concern but addresses by various grafting and component selection, not the primary concern of nerve injury with lengthening.
Question 1335
Topic: Pediatric Hip
A 55-year-old patient with a severe valgus neck-shaft angle (coxa valga) and femoral head hypoplasia secondary to Legg-Calve-Perthes disease in childhood presents with end-stage arthritis requiring THA. What specific technical consideration is paramount during femoral preparation in this case?
Correct Answer & Explanation
. Utilizing an undersized broach technique to prevent femoral fracture.
Explanation
Patients with Legg-Calve-Perthes disease often have significant proximal femoral deformities, including coxa valga, femoral head hypoplasia, and a narrowed, often anteverted femoral canal. These morphological abnormalities make femoral preparation challenging during THA. The narrowed canal, combined with the often dense bone, significantly increases the risk of intraoperative femoral fracture (Option D) during reaming and broaching. Therefore, using an undersized broach, careful progressive reaming, and potentially considering custom stems or non-standard stem designs are crucial. While addressing offset (Option E) and limb length discrepancy (Option C, with shortening osteotomy) are important considerations in THA, the immediate and most critical technical concern during femoral preparation in this specific context is preventing fracture. Reaming to avoid varus malpositioning (Option B) is important in any THA, but the specific anatomy of Perthes makes fracture a higher risk. Shorter stems (Option A) are not directly related to the unique challenges of Perthes morphology.
Question 1336
Topic: Pediatric Hip
A 13-year-old obese male presents to the emergency department unable to bear weight on his right leg after a minor slip. Radiographs reveal a severe slipped capital femoral epiphysis (SCFE). According to the Loder classification, this is an unstable SCFE. Which of the following best defines the primary clinical significance of an unstable SCFE?
Correct Answer & Explanation
. A substantially higher risk of avascular necrosis (AVN) of the femoral head
Explanation
The Loder classification divides SCFE into stable (able to bear weight with or without crutches) and unstable (unable to bear weight even with crutches). The primary clinical significance of an unstable SCFE is a dramatically higher risk of avascular necrosis (AVN), which can occur in up to 20-50% of unstable cases compared to nearly 0% in stable cases.
Question 1337
Topic: Pediatric Hip
A 10-week-old female infant with a completely dislocated, reducible developmental dysplasia of the hip (DDH) has been treated with a Pavlik harness for 2 weeks. The mother notes the child is no longer actively kicking her left leg, specifically lacking active knee extension. What is the most appropriate next step in management?
Correct Answer & Explanation
. Immediately discontinue the Pavlik harness and observe for neurologic recovery
Explanation
The clinical picture describes a femoral nerve palsy, a known complication of hyperflexion in a Pavlik harness. If a femoral nerve palsy develops, the harness must be discontinued immediately to allow for neurologic recovery, which typically resolves in days to weeks. Continuing the harness or increasing flexion can worsen the nerve injury.
Question 1338
Topic: Pediatric Hip
An 8-year-old boy is diagnosed with Legg-Calvé-Perthes disease. Radiographs demonstrate fragmentation of the femoral head with more than 50% loss of height of the lateral pillar. According to the Herring classification, what is the assigned group and expected prognosis without intervention?
Correct Answer & Explanation
. Group C; Poor prognosis, likely leading to aspherical incongruency
Explanation
The Herring lateral pillar classification divides LCPD into Groups A (no lateral pillar involvement), B (>50% lateral pillar height maintained), B/C border, and C (<50% lateral pillar height maintained). Group C signifies severe collapse and carries a poor prognosis with a high likelihood of developing a flattened, incongruous femoral head, especially in children older than 8 years.
Question 1339
Topic: Pediatric Hip
A 12-year-old boy presents with left-sided groin pain and an obligatory external rotation of the hip during active flexion. Radiographs confirm a left-sided Slipped Capital Femoral Epiphysis (SCFE). Which of the following patient factors represents the strongest indication for prophylactic in situ pinning of the contralateral, asymptomatic right hip?
Correct Answer & Explanation
. Presence of an underlying endocrinopathy, such as hypothyroidism
Explanation
Prophylactic pinning of the contralateral hip in SCFE is highly recommended in patients with endocrine or metabolic disorders (e.g., hypothyroidism, panhypopituitarism, renal osteodystrophy) or previous radiation therapy, as these conditions carry a bilateral involvement risk approaching 100%. While obesity is a risk factor for SCFE, it is not an absolute indication for prophylactic contralateral pinning without other high-risk features.
Question 1340
Topic: Pediatric Hip
An 8.5-year-old boy is diagnosed with Legg-Calvé-Perthes disease. AP and frog-leg lateral pelvic radiographs demonstrate exactly 50% maintenance of the lateral pillar height on the affected side. According to the prospective multicenter Herring study, what is the most appropriate management for this patient to optimize the long-term sphericity of the femoral head?
Correct Answer & Explanation
. Proximal femoral varus osteotomy or pelvic osteotomy
Explanation
The patient has Herring Lateral Pillar Group B or B/C border disease. The prospective Herring multicenter study demonstrated that for children older than 8 years of age at the time of onset with Lateral Pillar Group B or B/C border disease, surgical containment (such as a proximal femoral varus osteotomy or pelvic osteotomy) yields significantly better outcomes compared to nonoperative treatment. Children under 8 with Group B do well regardless of treatment, and Group C children do poorly regardless of treatment.
Test Yourself
Switch to an interactive, timed exam simulation to truly master this topic.
