Musculoskeletal · Pediatric Orthopedics
The facts most likely to be tested
The Barlow maneuver attempts to dislocate a stable hip by adducting and pushing the hip posteriorly.
The Ortolani maneuver attempts to relocate a dislocated hip by abducting and lifting the femoral head anteriorly.
Ultrasound of the hip is the diagnostic modality of choice for infants younger than 4 to 6 months of age.
Radiographs of the pelvis are the preferred diagnostic tool for infants older than 6 months due to the ossification of the femoral head.
Breech presentation, female sex, and family history are the most significant risk factors for developing the condition.
The Pavlik harness is the gold-standard initial treatment for infants younger than 6 months to maintain the hip in flexion and abduction.
Delayed diagnosis of developmental dysplasia of the hip can lead to avascular necrosis of the femoral head and permanent gait abnormalities.
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A 3-week-old female infant is brought to the clinic for a routine well-child check. She was born at 39 weeks gestation via breech presentation. On physical examination, the pediatrician notes an asymmetric gluteal fold and a palpable clunk when performing an abduction maneuver on the left hip. The right hip examination is unremarkable. The infant is otherwise healthy and meeting all developmental milestones.
What is the most appropriate next step in management?
Hip ultrasound
The patient presents with classic signs of developmental dysplasia of the hip (breech history, asymmetric folds, positive Ortolani/Barlow), and ultrasound is the diagnostic test of choice for infants under 6 months.
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Etiology / Epidemiology
Common in breech presentation, female sex, and family history. Results from abnormal acetabular development.
Clinical Manifestations
Positive Ortolani and Barlow maneuvers. Asymmetric skin folds and leg length discrepancy.
Diagnosis
Hip ultrasound is the gold standard for infants <4 months. Radiographs used after 4-6 months.
Treatment
Pavlik harness is the first-line treatment. Avoid forced abduction to prevent avascular necrosis.
Prognosis
Early detection prevents avascular necrosis and permanent gait abnormalities.
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Epidemiology & Etiology
Incidence is highest in first-born females and those with a history of breech positioning in utero. Mechanical factors like oligohydramnios and swaddling practices contribute to joint laxity. Genetic predisposition is significant, requiring screening for all siblings of affected patients.
Pertinent Anatomy
The acetabulum is shallow, failing to adequately cover the femoral head. This anatomical instability allows the femoral head to subluxate or dislocate from the acetabulum.
Pathophysiology
Persistent instability leads to secondary changes in the acetabular labrum and capsule. If untreated, the femoral head remains displaced, causing the acetabulum to flatten and the femoral head to undergo avascular necrosis. Chronic dislocation results in permanent structural deformity and early-onset osteoarthritis.
Clinical Manifestations
Infants present with a positive Ortolani (reduction of dislocated hip) or Barlow (dislocation of reduced hip) maneuver. Look for asymmetric inguinal skin folds and limited hip abduction. Red flag: A late-presenting child may exhibit a Trendelenburg gait or a painless limp.
Diagnosis
Hip ultrasound is the diagnostic modality of choice for infants <4 months due to cartilaginous anatomy. After 4-6 months, the femoral head ossifies, making AP pelvis radiographs the preferred study. The alpha angle on ultrasound is the critical metric for assessing acetabular depth.
Treatment
The Pavlik harness is the gold standard for infants <6 months, maintaining the hip in flexion and abduction. Do not use rigid bracing initially due to the risk of avascular necrosis. If the harness fails or the patient is older, closed reduction under anesthesia or open surgical reduction is required.
Prognosis
Early intervention leads to excellent outcomes with normal hip development. Delayed diagnosis significantly increases the risk of permanent hip dysplasia, chronic pain, and the need for total hip arthroplasty in early adulthood.
Differential Diagnosis
Septic arthritis: acute fever and refusal to bear weight
Legg-Calvé-Perthes disease: idiopathic avascular necrosis in older children
Slipped Capital Femoral Epiphysis: adolescent onset with external rotation
Transient synovitis: follows viral illness, self-limiting
Femoral nerve palsy: weakness in knee extension